Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.18343/jipi.29.2.236

Other Link： https://www.researchgate.net/publication/379993519_Karakter_Morfo-agronomi_Tanaman_Cabai_Merah_Capsicum_annum_L_Fase_Awal_Vegetatif_pada_Kondisi_Stres_Jenuh_Air_Morpho-agronomic_Characters_of_Chili_Pepper_Capsicum_annum_L_on_Early_Vegetative_Stage_und

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.plaphy.2024.108494

Other Link： https://doi.org/10.1016/j.plaphy.2024.108494

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1755-1315/1362/1/012041

Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/1362/1/012041

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.4067/S0718-58392024000300425

Other Link： https://oes.chileanjar.cl/files/CJAR240019-84-3-2024.pdf

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/plants13010003

Other Link： https://doi.org/10.3390/plants13010003

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/su152115402

Other Link： https://www.mdpi.com/2071-1050/15/21/15402

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1155/2023/1954632

Other Link： https://www.hindawi.com/journals/tswj/2023/1954632/

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/app13052869

Other Link： https://www.mdpi.com/2076-3417/13/5/2869

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.rhisph.2023.100688

Other Link： https://www.sciencedirect.com/science/article/abs/pii/S2452219823000277?via%3Dihub

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.rhisph.2022.100644

Other Link： https://www.sciencedirect.com/science/article/pii/S2452219822001744?via%3Dihub

Authorship：Corresponding author   Language：English  

DOI： https://doi.org/10.1063/5.0116389

Other Link： https://aip.scitation.org/doi/abs/10.1063/5.0116389

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.24425/jppr.2023.144502

Other Link： https://www.journals.pan.pl/dlibra/publication/144502/edition/126133/content

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1007/s11120-022-00959-y

Other Link： https://link.springer.com/article/10.1007/s11120-022-00959-y

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1155/2022/1972585

Other Link： https://www.hindawi.com/journals/aess/2022/1972585/

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/plants11081039

Other Link： https://doi.org/10.3390/plants11081039

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1080/1343943X.2022.2054830

Other Link： https://cogentoa.tandfonline.com/doi/pdf/10.1080/1343943X.2022.2054830

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1002/csc2.20736

Other Link： https://acsess.onlinelibrary.wiley.com/doi/abs/10.1002/csc2.20736

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1515/opag-2022-0067

Other Link： https://www.degruyter.com/document/doi/10.1515/opag-2022-0067/html

Authorship：Corresponding author   Language：English  

DOI： https://doi.org/10.1016/j.scienta.2022.111337

Other Link： https://www.sciencedirect.com/science/article/pii/S0304423822004587

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3934/agrfood.2022001

Other Link： https://www.aimspress.com/article/doi/10.3934/agrfood.2022001

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.13057/biodiv/d230250

Other Link： https://www.smujo.id/biodiv/article/view/10196

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/agronomy11102021

Other Link： https://www.mdpi.com/2073-4395/11/10/2021/htm

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3934/agrfood.2021043

Other Link： https://aimspress.com/article/doi/10.3934/agrfood.2021043

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.scienta.2021.109943

Other Link： https://www.sciencedirect.com/science/article/pii/S0304423821000509

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.58297/EWNR4619

Other Link： https://sarr.co.in/2022/07/01/biochar-a-climate-smart-practice-for-milling-traits-and-aroma-of-fragrant-rice-under-drought-stress-with-different-time-of-harvest/

Language：Japanese   Publisher：Plants  

Hydropriming rice seeds effectively improve the germination percentage, shortens the germination period, and promotes seedling growth. The impact of seed hydropriming is to speed up growth under dry soil conditions, thereby avoiding drought damage. This study analyzes the effect of hydropriming on morpho-physiological changes in the water uptake of rice seeds using “Kasalath” and “Nipponbare” under water-deficit conditions. Upon exposure to osmotic stress, both varieties showed delays in the time to reach germination. In addition, all germination phases exhibited reductions in the activity of alpha-amylase and total soluble sugar by osmotic stress; however, in all germination phases of the hydroprimed seeds, the activity and contents of those were significantly increased, resulting in increased size of the coleoptile, plumule, and radicle. In hydroprimed seeds, “Kasalath” was superior to “Nipponbare” in the ratio of the water-deficit-to-well-watered conditions for all traits related to germination, which may have been attributable to hydropriming having a greater effect on “Kasalath”. Interestingly, Primed “Kasalath” had a lower level of α-amylase, despite the having a higher content of total soluble sugars than primed “Nipponbare”.

DOI： 10.3390/plants13243537

Scopus

PubMed

Language：Japanese   Publisher：Pancreatology  

Background: The natural history of branch-duct intraductal papillary mucinous cystic neoplasms (BD-IPMNs) in the pancreas remains unclear. This study aimed to answer this clinical question by focusing on the development of concomitant pancreatic ductal adenocarcinomas (cPDAC). Methods: The Japan Pancreas Society conducted a prospective multicenter surveillance study of BD-IPMN every six months for five years. The primary endpoints were progression of BD-IPMN, progression to high-grade dysplasia/invasive carcinoma (HGD/IC), and cPDAC. Factors predicting the progression of BD-IPMN to HGD/IC and development of cPDAC were also assessed as secondary endpoints. Results: Among the 2104 non-operated patients, 348 (16.5 %) showed progression of primary BD-IPMN. Cumulative incidences of BD-IPMN with HGD/IC and cPDAC during the 5.17-year surveillance period were 1.90 % and 2.11 %, respectively, and standard incidence ratios of BD-IPMN with HGD/IC and cPDAC were 5.28 and 5.73, respectively. Of 38 cPDACs diagnosed during surveillance, 25 (65.8 %) were resectable. The significant predictive characteristics of BD-IPMN for progression to HGD/IC were larger cyst size (p = 0.03), larger main pancreatic duct size (p < 0.01), and mural nodules (p = 0.02). Significant predictive characteristics for the development of cPDAC were male sex (p = 0.03) and older age (p = 0.02), while the size of IPMN was not significant. Conclusion: Careful attention should be given to “dual carcinogenesis” during BD-IPMN surveillance, indicating the progression of BD-IPMN to HGD/IC and development of cPDAC distinct from BD-IPMN, although the establishment of risk factors that predict cPDAC development remains a challenge (UMIN000007349).

DOI： 10.1016/j.pan.2024.08.013

Scopus

PubMed

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.258.0_27

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.258.0_106

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.258.0_112

Language：Japanese   Publisher：Agronomy  

Achieving a consistent grain yield while preserving persistent aroma remains a substantial challenge in aromatic rice production in Bangladesh. To address this challenge, a field experiment was conducted at the agronomy research area of Sher-e-Bangla Agricultural University, Dhaka-1207, between 15 June 2022, and 25 November 2022 (Aman season). This study aimed to evaluate the influence of harvesting time on aromatic rice performance. The experiment, following a randomized complete block design with three replications, involved two factors: factor 1 comprised various rice varieties [Bangladesh Rice Research Institute (BRRI) dhan34, BRRI dhan70, BRRI dhan80, and Tulshimala], and factor 2 comprised three harvesting times [3, 4, and 5 weeks after flowering (WAF)]. Results revealed significant impacts of variety and/or harvesting time on grain yield, physicochemical characteristics, and aroma of aromatic rice. Notably, Tulshimala and BRRI dhan80 exhibited superior milling quality, biochemical properties, and aroma characteristics among the aromatic rice types. BRRI dhan70 and BRRI dhan80 displayed higher grain yield when harvested at 5 WAF. However, Tulshimala and BRRI dhan80 showed superiority in grain 2-acetyl-1-pyrroline (2-AP) concentration when harvested 3 or 4 WAF. Earlier harvesting at 3 and 4 WAF resulted in higher percentages of grain 2-AP (60.22% and 53.96%, respectively) compared with later harvesting at 5 WAF (used as check). In conclusion, varying harvesting times markedly impact the yield, physiochemical characteristics, and aroma of aromatic rice varieties, with earlier harvesting beneficial for aroma retention in Tulshimala and BRRI Dhan80 and later harvesting for increased economic yield in BRRI dhan70 and BRRI dhan80.

DOI： 10.3390/agronomy14081714

Scopus

Language：Japanese   Publisher：Chilean Journal of Agricultural Research  

Red chili pepper Capsicum annuum L. var. annuum plants are one of the fruity vegetable types that are often cultivated in riparian tropical wetlands but are constrained by water stress such as waterlogging during rainy season and drought in dry season. The aim of this research was to evaluate the growth and morphophysiological responses of red chili pepper cultivars subjected to waterlogging and drought stress conditions. The experiment was carried out in a strip-plot design with two factors. The first factor was three water stress treatments, namely control (field capacity), waterlogging, and drought. The second factor was six cultivars of Indonesian red chili pepper. The findings indicated that both waterlogging and drought stress had a detrimental impact on the reduction of the growth parameters of red chili pepper such as root, shoot and total dry weight. Chili pepper defended its root weights in response to drought stress (0.653 g plant-1) whereas it preserved shoot weight in response to waterlogging (0.913 g plant-1). In the morphological characters, chili pepper exhibited an increase in specific leaf area expansion in response to both waterlogging (150.82 cm2) and drought (188.82 cm2) compared to control (140.91 cm2), but decreased specific leaf weight during stresses and recovered after 7 d in waterlogging. Leaf chlorophyll content (SPAD) and leaf relative water content (LRWC), as physiological characteristics, also experienced a decline during exposure to both waterlogging and drought during 8 d; yet, SPAD and LRWC able to recover completely at 7 d after waterlogging and drought treatment were terminated.

DOI： 10.4067/S0718-58392024000300425

Scopus

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.257.0_54

Language：Japanese   Publisher：Plant Physiology and Biochemistry  

The role of halopriming in alleviating the detrimental effects of salinity and combined salinity-submergence was evaluated using two rice genotypes, “IR06F148” (anaerobic germination + submergence tolerant [Sub1]) and “Salt-star” (salt tolerant) with contrasting levels of tolerance. Nonprimed seeds and those primed with 1% calcium chloride (CaCl2) were germinated, and the seedlings were exposed to salinity (50 or 100 mM sodium chloride [NaCl]) and submergence (nonsaline or saline water). Salinity substantially inhibited plant height, shoot/root dry mass, and leaf area. Priming improved the resilience to 50 mM NaCl by increasing the chlorophyll content and lowering hydrogen peroxide (H2O2) production; and to 100 mM NaCl by increasing the total soluble sugars. However, apparent differences in the responses of primed “Salt-star”, such as an increase in the Na+, K+, and Ca2+ levels, indicated that halopriming differentially affected the response to salt based on the salinity tolerance of the variety. Submergence reduced the shoot biomass, chlorophyll, and photosynthetic efficiency to a greater extent in “Salt-star” than in “IR06F148”. Priming, especially in “Salt-star”, caused a lesser reduction in the chlorophyll (Chl) and maximum quantum yield of photosystem II (Fv/Fm) but increased the total soluble sugars post-submergence, indicating a boost in the photosynthetic efficiency. The responses of the two varieties to submergence depended on their tolerance, and halopriming affected each variety differently. The metabolic and molecular changes induced by halopriming in submergence-tolerant rice may be explored further to understand the underlying mechanisms of improved resilience.

DOI： 10.1016/j.plaphy.2024.108494

Scopus

PubMed

Language：Japanese   Publisher：Plants  

While internal aeration in plants is critical for adaptation to waterlogging, there is a gap in understanding the differences in oxygen diffusion gradients from shoots to roots between hypoxia-tolerant and -sensitive species. This study aims to elucidate the differences in tissue oxygen concentration at various locations on the shoot and root between a hypoxia-tolerant species and a -sensitive species using a microneedle sensor that allows for spatial oxygen profiling. Job’s tears, a hypoxia-tolerant species, and sorghum, a hypoxia-susceptible species, were tested. Plants aged 10 days were acclimated to a hypoxic agar solution for 12 days. Oxygen was profiled near the root tip, root base, root shoot junction, stem, and leaf. An anatomical analysis was also performed on the roots used for the O2 profile. The oxygen partial pressure (pO2) values at the root base and tip of sorghum were significantly lower than that of the root of Job’s tears. At the base of the root of Job’s tears, pO2 rapidly decreased from the root cortex to the surface, indicating a function to inhibit oxygen leakage. No significant differences in pO2 between the species were identified in the shoot part. The root cortex to stele ratio was significantly higher from the root tip to the base in Job’s tears compared to sorghum. The pO2 gradient began to differ greatly at the root shoot junction and root base longitudinally, and between the cortex and stele radially, between Job’s tears and sorghum. Differences in the root oxygen retention capacity and the cortex to stele ratio are considered to be related to differences in pO2.

DOI： 10.3390/plants13010003

Scopus

PubMed

Language：Japanese   Publisher：IOP Conference Series: Earth and Environmental Science  

Tropical riparian wetland known as non-tidal lowland is potential land for agriculture, especially for vegetable cultivation such as red chili pepper (Capsicum annum L.). Transitional period (dry to rainy season) has a chance for red chili pepper cultivation in the field (at low tide conditions), but has risk of experiencing dynamic water table to waterlogging in early rainy season. The aim of this research was to determine the effects of physiological traits of red chili pepper exposure on short-term (4 days) waterlogging. This study was done at the Tropical Crop Science Laboratory, Kagoshima University, Japan. The experiment was designed as a completely randomized factorial design. The first factor was control/field capacity and waterlogging (entire growing media was submerged). The second factor was chili variety, consisting of Laris and Romario. Treatments began 14 days after transplanting, lasted four days, then followed by seven days of recovery. The results of this study showed that there were changes in photosynthetic characters between before waterlogging, after waterlogging and after recovery time, between control and waterlogging, and also between Laris and Romario. Photosynthetic and transpiration rates decreased sharply under waterlogging in after waterlogging, but increased in after recovery period on Laris, opposite on Romario. Changes occur were associated with the decline in stomatal conductance and chlorophyll fluorescence as a response to waterlogging stress. Laris as a resistant variety has the ability to recover under short-term stress conditions, so it needs to be further developed for cultivation in tropical riparian wetlands.

DOI： 10.1088/1755-1315/1362/1/012041

Scopus

Language：Japanese   Publisher：AIMS Agriculture and Food  

One constraint is the incapacity of existing agronomic studies on rice yield, aroma, and cooking quality to fully assess the effects of various applications and sources of nitrogen (N) fertilizer. It is challenging for us to understand how different N inputs impact rice’s sensory and cooking qualities in addition to crop productivity because of this research gap. So, a two-year pot experiment was conducted at Sher-e-Bangla Agricultural University, Dhaka, under an open field plastic net house from July 15 to December 4 in 2020 and 2021. The study used Bangladesh Rice Research Institute (BRRI) dhan70 as the test crop. The experiment examined two factors: the methods and source of N application. Three methods of N application were tested: 100% soil application (NM1), 2% foliar spray at tillering and booting stages (NM2), and a combination of 50% soil application and 2% foliar spray at the booting stage (NM3). Three sources of N were also evaluated: Urea (NS1), ammonium nitrate (NS2), and ammonium sulfate (NS3). Total 41.0 kg N ha−1 was applied considering the nitrogen content in Urea (46%), ammonium nitrate (35%), and ammonium sulfate (21%). The experiment followed a randomized complete block design (RCBD) with three replications. The results indicated that the application of N significantly influenced most of the studied parameters. The combined application of N as a foliar dose and soil application, along with ammonium nitrate and ammonium sulfate, showed improved results for various parameters such as gelatinization temperature, gel consistency, protein content, cooking time, imbibition ratio, 2-AP content, grain aroma, and taste of BRRI dhan70 compared to 100% soil application of N. The highest grain yield and 2-AP was observed in the NM3NS3 treatment (35.437 g·pot−1 and 0.137 µg·g−1, respectively) which was statistical similar with NM3NS2 treatment while the lowest yield and 2-AP was recorded in NM1NS1 (24.877 g·pot−1 and 0.076 µg·g−1, respectively).

DOI： 10.3934/AGRFOOD.2024055

Scopus

Language：Japanese   Publisher：All Life  

The experiment was conducted at the research area of Sher-e-Bangla Agricultural University from 15 June 2022, to 25 November 2022 (Aman season) to evaluate the impact of aromatic compound application on fragrant rice. The experiment included two factors: factor 1 comprised four rice varieties (BRRI dhan34, BRRI dhan70, BRRI dhan80, and Tulshimala), and factor 2 comprised application of four aromatic compounds (L-proline, α-ketoglutaric acid, γ-aminobutyric acid, and sodium selenite). A randomized complete block design was employed with three replications. Results revealed significant effects of aromatic compound applications and/or rice varieties on grain eating qualities, sensory aroma and 2-acetyl-1-pyrroline, which were superior in Tulshimala and BRRI dhan34. α-Ketoglutaric acid and sodium selenite application improved water uptake ratio, amylose and amylopectin content, alkali spreading value, gel consistency, protein content, sensory aroma score, and kernel stickiness and tenderness of fragrant rice. Moreover, α-ketoglutaric acid application led to enhanced 2-acetyl-1-pyrroline content in Tulshimala and BRRI dhan34. Several eating quality and fragrance parameters were found either positively or negatively correlated. Apparent amylose content exhibited a negative correlation with stickiness of kernel. Sensory aroma and grain 2-AP content were also positively correlated.

DOI： 10.1080/26895293.2024.2407897

Scopus

Language：Japanese   Publisher：Journal of Plant Growth Regulation  

Enhancing aroma retention is pivotal for the production and exportation of aromatic rice in Bangladesh. In this study, a 2-year pot experiment was conducted to assess the effects of γ-aminobutyric acid (GABA) application on aromatic rice under shading and drought stress conditions. The rice variety, BRRI (Bangladesh Rice Research Institute) dhan80 was used as the planting material to investigate with the following eight treatments: (T1) no GABA, shading, or drought stress treatment; (T2) GABA application at 250 mg/L during panicle initiation; (T3) shading at the grain filling stage; (T4) drought stress at the grain filling stage; (T5) shading and drought stress at the grain filling stage; (T6) GABA application at 250 mg/L at panicle initiation and shading at the grain filling stage; (T7) GABA application at 250 mg/L at panicle initiation and drought stress at the grain filling stage; and (T8) GABA application at 250 mg/L at panicle initiation as well as shading and drought stress at the grain filling stage. A randomized complete block design was followed, with treatments replicated five times. Results revealed GABA application along with shading and drought stress significantly influenced most studied traits. Notably, 250 mg/L GABA application at panicle initiation, alongside shading and drought stress at the grain filling stage, resulted in favorable outcomes for the brown rice yield, head rice recovery, amylose and protein content, grain 2-acetyl-1-pyrroline content, grain aroma, and taste of BRRI dhan80 rice compared with the control group (T1). However, the control treatment exhibited the highest grain yield compared with the other treatments. Overall, GABA application combined with shading and drought stress markedly improved grain quality and aroma of BRRI dhan80 but affected grain yield in an inverse manner.

DOI： 10.1007/s00344-024-11513-6

Scopus

Language：Japanese   Publisher：Sustainability (Switzerland)  

Phosphorus (P) deficiency resulting from P fixation is a major constraint limiting sustainable rice cultivation in sub-Saharan Africa. Soil texture also affects P availability and use efficiency. In a factorial experiment, we evaluated the combined effect of soil texture (sand, clay loam, and clay) and P treatments P-dipping (Pdip) and two other broadcasted P fertilizer levels (Brod1 and Brod2) on the growth of NERICA 4 rice in the initial growth stages. Across all soil textures and P treatments, total plant biomass ranged from 1.06 to 4.63 g pot−1. The Pdip treatment significantly increased shoot and root biomass relative to control from 1.27 to 1.98 and 0.23 to 0.38 g pot−1, respectively. Mean photosynthetic rate values under Pdip (20.1 μmol m−2 s−1), Brod2 (19.5 μmol m−2 s−1), and Brod1 (19.3 μmol m−2 s−1) treatments showed significant 42%, 37%, and 36% increases over control, regardless of soil texture. In a striking contrast, P-dipping significantly promoted growth of root length under clay soil, but without a commensurate increase in shoot P uptake. Contrary to our hypothesis, the interactive effect of soil texture and P-dipping influenced NERICA 4 shoot and root physiological and morphological characteristics under clay loam soil texture as opposed to clay.

DOI： 10.3390/su152115402

Scopus

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.256.0_21

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.256.0_62

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.256.0_37

Language：Japanese   Publisher：Rhizosphere  

Drought stress and phosphorus (P) deficiency are major abiotic factors that limit the yields of rice in Sub-Saharan Africa. To improve the available P supply in the highly weathered soils in the region, farmers use several P application methods, one of which is P-dipping, i.e., dipping the root of seedlings into P-enriched slurry before transplanting. In this study, a split-plot pot experiment was conducted to determine how the effect of localized P application via P-dipping (using four P fertilizer levels) on NERICA 4 rice growth interacts with two water regimes (waterlogging and moderately dry). Shoot dry weight and plant height differed significantly under the various P-dipping application levels, with an application of 40 kg P ha−1 providing the highest mean values under both water treatments. While the mean leaf area did not statistically differ among the P-dipping treatment levels under the moderately dry condition, all P-dipping treatments had increased leaf area relative to that observed without P-dipping. Mean root length differed significantly between the water treatments, whereas the mean root dry weight was higher with the P-dipping treatments than without P-dipping under both water conditions (36% and 8% mean increases under the waterlogged and moderately dry treatments, respectively). These findings show that P-dipping improves the ability of NERICA 4 rice seedlings to withstand water and nutrient stresses under rainfed lowland at early growth stages.

DOI： 10.1016/j.rhisph.2023.100688

Scopus

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.255.0_27

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.255.0_25

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.255.0_26

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.255.0_54

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.255.0_191

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.255.0_34

Language：Japanese   Publisher：Rhizosphere  

As rice is cultivated under diverse moisture conditions from paddy to field, the internal morphology of their roots may be diverse within species. This study aimed to investigate which traits affect the root oxygen consumption and transportation ability using rice varieties with different root anatomical traits. First, the CSR of seminal roots of six rice varieties was used to identify a variety with a low CSR. Results showed that the CSR in Sensho was the lowest in both aerated and stagnant solutions. Second, the shoot morphological traits, root anatomical traits, and root oxygen consumption and transportation of four rice varieties, including Sensho, were examined in preaerated and deoxygenated agar solutions. Results showed that deoxygenated conditions did not have any negative effects on the growth of the rice varieties. The root oxygen consumption rates were strongly positively correlated with the leaf area/root dry weight (LA/RDW, r = 0.90). The root oxygen transportation rates were also positively correlated with LA/RDW (r = 0.57). The percentage of root oxygen consumption compensated by oxygen transportation was highest in IR42, which had a low LA/RDW. Multiple regression using stomatal conductance, LA/RDW, and shoot dry weight as explanatory variables explained only 65.0% of oxygen transportation. We concluded that further studies on gas movements inside the shoots and roots are needed to clarify the mechanism that provides more sufficient oxygen to the roots.

DOI： 10.1016/j.rhisph.2022.100644

Scopus

Language：Japanese   Publisher：Applied Sciences (Switzerland)  

Featured Application: Seed longevity is an attribute that deserves consideration in the adoption and in informing the assessment of seed priming. Seed survival after priming is higher for varieties that can withstand damage and ageing better even in adverse conditions. Agriculture depends on the ability of seeds to survive until the next planting season under ambient conditions that may be averse to seed quality even when the seed is in a quiescent state. Seed priming invigorates seeds, but the impact on the longevity of seeds has limited its adoption. This study investigated the effect of the storage of primed rice seed on seed viability, vigor, and longevity. Three seed priming methods were employed on the rice cultivar New Rice for Africa (NERICA 4) seeds. Subsequently, the seeds were stored for 120 days at 25 °C and 65% relative humidity, simulating the ambient seed storage conditions of the tropics and sub-tropics. The primed seed recorded increased vigor compared to the non-primed seed until 90 days of storage. However, seed storage for 120 days reduced seed vigor and viability for all the seeds. The results indicated a significant reduction in seed vigor, increased solute leakage, generation of hydrogen peroxide, and accumulation of malondialdehyde after storage. Priming enhances cell membrane integrity and maintains seed vigor in storage at near ambient conditions long enough before reversal of its performance by the storage conditions. This assures that primed seed can either be stored until the following planting season or remain viable in the soil during delayed germination.

DOI： 10.3390/app13052869

Scopus

Language：Japanese   Publisher：AIP Conference Proceedings  

Water saturated rhizosphere (WSR) can be caused by partial submergence of growing substrate such as in floating culture system (FCS). This WSR directly influence metabolism and development in root and leaves. This study focused to assess responses of root and leaves of nine Indonesian varieties of chili peppers exposed to two levels of WSR conditions, i.e. 1/3 WSR (W1) and fully WSR (W2). These WSR treatments were compared to untreated control plant (C0). The results showed that WSR treatments decreased leaf parameters such as number of existing leaves at end of treatments, SPAD value, total leaf area (TLA), specific leaf dry weight (SLDW), and relative turgidity (RT). Effect on root parameters included decrease of root length (RL) and ratio of root dry weight (RDW). However, 1/3 WSR treatment exhibited higher values of both root and leaf parameters than those of control plants in some varieties. There were comparable patterns of RLER in the 1/3 WSR treated plants (W1) and untreated control (C). Based on results of this study, it is recommendable to allow up to 1/3 lower part of growing substrate to be submerged in floating culture system of chili pepper.

DOI： 10.1063/5.0116389

Scopus

Language：Japanese   Publisher：Journal of Plant Protection Research  

The objective of this study was to evaluate the antagonistic activity of Trichoderma spp. against wild pathogen Fusarium oxysporum F.28.1A, which causes wilt disease on sesame. Twenty-six isolates of Trichoderma spp. isolated from soil samples were tested to control F. oxysporum F.28.1A. Prescreening showed that five isolates were T-02B1, T-18B2, T-20B1, T-28B1, and T-29A1, based on the lowest values of colony radius of F. oxysporum F.28.1A. The selected isolates were identified by their ITS region as T. yunnanense T-02B1, T. lentiforme T-18B2, T. asperellum T-20B1, T. hamatum T-28B1, and T. hamatum T-29A1, with similarities around 96–100%. The isolates selected were able to produce enzymes including chitinase, exo-β-1,3-glucanase, and endo-β-1,3-glucanase at levels of 0.34–0.44, 0.017–0.034, and 0.032–0.121 UI · ml–1, respectively, which were considered to be a mechanism to prevent the growth of F. oxysporum F.28.1A. The isolates tested were applied in soil pots to prevent damage from F. oxysporum F.28.1A as a following experiment. The greenhouse experiment was arranged in a completely randomized design with 10 treatments, including a negative control, application of only F. oxysporum F.28.1A, application of both F. oxysporum F.28.1A and fungicide chemicals, application of both F. oxysporum F.28.1A and Trichoderma spp. DHCT, application of T. yunnanense T-02B1, application of T. lentiforme T-18B2, application of T. asperellum T-20B1, application of T. hamatum T-28B1, application of T. hamatum T-29A1 and a mixture of the five selected isolates of Trichoderma spp. with their total population equal to that in individual strain application. The results showed that the five mixed isolates of Trichoderma had a synergistic effect on the reduction of the disease’s prevalence by 35% compared to the negative control treatment.

DOI： 10.24425/jppr.2023.144502

Scopus

Language：English  

DOI： 10.1155/2023/1954632

PubMed

Language：Japanese   Publisher：Scientia Horticulturae  

Oxidants produced by roots in hypoxic soil and stress caused by intense light are two causes of reduced photosynthetic capacity and efficiency. Moreover, they promote the formation of leaf abscission zones, which has detrimental effects on crop growth. It remains unclear how leaf position, an endogenous factor in nonstress-induced senescence, affects leaf senescence caused by oxidative stress. Thus, we used Capsicum plants to examine how leaf senescence and abscission changed photosynthetic capacity and efficiency at five leaf positions. We analyzed the association between photosynthetic changes and leaf abscission. Our results demonstrated that hypoxia resulted in lower root biomass, lower water uptake in leaves, and lower leaf carotenoid content. Moreover, the interaction between hypoxia and intense light stress causes lower carotenoid and chlorophyll content, suggesting that leaf oxidative stress levels affect the degree of photoprotection conferred by the presence of carotenoids. We also found a significant reduction in the maximum quantum yield of photosystem II under hypoxia conditions, especially in leaves at lower positions on the plant. Finally, we observed that the combined stress of hypoxia and intense light induced abscission at these lower leaf positions. Our results suggested that the level of oxidative damage in respective leaf caused by hypoxia and high light stress is significantly affected by leaf position, and stress interactions cause abscission in the lower leaves near the roots.

DOI： 10.1016/j.scienta.2022.111337

Scopus

Language：Japanese   Publisher：Photosynthesis Research  

This study investigated the effect of transient submergence on the recovery of photosynthetic activity and translocation of photosynthate in IR67520 (Sub1A genotype) and IR72442 (non-Sub1A genotype) using 13C-labeled tracer, coupled with some photosynthetic physiological assessments. Plant growth, photosynthetic capacity, and photosynthetic recovery were studied by treating the two rice genotypes without or completely submerged for 7 days in transparent acrylic tanks filled with water to a depth of 80 cm, followed by 7 days of reaeration. Results revealed that the IR67520 was able to obtain new carbon source for assimilation during at 7 days of recovery periods. The IR72442 genotype partitioned 13C to the newly developed upper leaves more than the IR67520 genotype did. This was due to its inability to obtain CO2 from other source during post submergence. Recovery of chlorophyll content, ability to retain higher biomass, and ability to grow faster at 7 days of recovery periods also indicated the ability of Sub1A genotype to reactivate its photosynthetic capacity.

DOI： 10.1007/s11120-022-00959-y

Scopus

PubMed

Language：Japanese   Publisher：日本作物学会  

DOI： 10.1626/jcs.91.256

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1155/2022/1972585

Other Link： https://www.hindawi.com/journals/aess/2022/1972585/

Language：Japanese   Publisher：Plants  

Environmental responses of stomatal conductance (gs) as basic information for a photo-synthesis-transpiration-coupled model have been increasing under global warming. This study identified the impact of gs behavior under different soil water statuses and temperatures in rice, maize, millet, and sorghum. The experiments consisted of various soil moisture statuses from flooding to drying and combination of soil moisture status and temperature. There was a reduction in shoot biomass of maize and sorghum caused by decreasing of gs, photosynthesis (A), and transpiration (E) in early imposed waterlogging without dependent temperature, whereas millet and rice were dependent on temperature variation. The effect of gradual soil drying, gs, A, and E of maize, millet, and sorghum were caused by low temperature, except rice. The impact of the combination of various soil water statuses and temperatures on gs is important for the trade-off between A and E, and consequently shoot biomass. However, we discovered that an ability to sustain gs is essential for photo assimilation and maintaining leaf temperature through evapotranspiration for biomass production, a mechanism of crop avoidance in variable soil water status and temperature.

DOI： 10.3390/plants11081039

Scopus

PubMed

Language：Japanese   Publisher：Open Agriculture  

The objective of this study was to determine the optimal concentration of boron (B) to obtain the highest growth, yield, and oil content of black sesame. A field experiment was conducted in a completely randomized block design with five treatments and five replications. Treatments included foliar application of B at five rates: control, 50, 100, 150, and 200 mg L-1 at 25 and 35 days after sowing. Results showed that spraying B on leaves increased sesame growth in terms of plant height, number of leaves, and chlorophyll content. Moreover, spraying B increased yield components including the number of pods; the highest pods per plant was 46.2 in the B application treatment with 150 mg L-1 compared to the control with 27.2 pods per plant. The grain yield of the B spray treatment produced 1.10-1.32 t ha-1, with the highest yield at the dose of 150 mg L-1 and the lowest yield at no B spray treatment. Spraying B on leaves at optimal concentration also increased the oil content in seeds up to 5.3% compared to the control treatment. The findings of the study suggest that foliar B application with 150 mg L-1 increases the growth, fruit set, seed yield, and oil content in sesame.

DOI： 10.1515/opag-2022-0067

Scopus

Language：Japanese   Publisher：Plant Production Science  

This study investigated the interactions between soil moisture conditions and seed priming on initial and late growth over 2 years (2017–2018) through field trials and container experiments with regulated soil moisture. Field trials were conducted on rainfed upland rice fields in Uganda, East Africa, where primed and control seeds were planted in triplicate and cultivated. In 2017, the percentage of first heading (head emergence) of hills was higher in priming treatments, and the time for 20% of the hills to achieve the first heading (H20) was significantly earlier than in controls. Additionally, grain ratio (number of fertile grains to sterile grains) and H20 were negatively correlated (P < 0.05). However, the difference in growth parameters between control and priming was not found in the case of 2018. The results suggested that priming reduces the growth period under certain conditions and improves drought escape. Therefore, we investigated the relationship between priming effects on initial growth under soil moisture treatments and subsequent development under waterlogged conditions. After transfer to waterlogged conditions, plants of the primed seeds initially grown in low soil moisture conditions recovered earlier than control plants. Our research concludes that the agronomical impact of hydropriming on upland rice prevents prolonged plant growth under drought by early recovery. Furthermore, it could decrease the yield loss caused by reduced rainfall in the late growth stage.

DOI： 10.1080/1343943X.2022.2054830

Scopus

Language：Japanese   Publisher：Biodiversitas  

Zarwazi LM, Junaedi A, Sopandie D, Sugiyanta, Purwono, Sakagami J-I. 2022. Prospective rice varieties for high yield performance on modified ratoon salibu cultivation. Biodiversitas 23: 1065-1071. Modified Ratoon Salibu (MRS) differs from ratoon (Conventional Ratoon, CR). This research aims to investigate some rice varieties re-grown as CR and MRS after main crops are harvested. The experiment was conducted at Kuningan Experimental Station of Indonesian Center for Rice Research, using rice varieties as the main plot (Hipa 18, Hipa 19, Inpari 42, Inpari 43, IPB 3S, and Batang Piaman), and ratoon cultivation system as a sub-plot (CR and MRS), evaluated in the first (1) and second (2) generation after the main crop. The result showed that the growth character of MRS on plant height, stem diameter, blade-leaf size, root volume was significantly higher than that of CR. Furthermore, the yield component and yield were also significantly higher in MRS than CR. The CR yielded about 56.9 and 10.8 % of the main crops for R1 and R2, respectively, whereas MRS yielded 121.0 and 93.8% of the main crops for MR1 and MR2, respectively. This finding could be a scientifically proven of local wisdom “Salibu” indigenous knowledge in Tanah Datar District of West Sumatera. Therefore, MRS could be recommended for suitable varieties and environmental conditions as the sustainable farming alternative to increase Cropping Index while still reaching high productivity.

DOI： 10.13057/biodiv/d230250

Scopus

Language：Japanese   Publisher：International Center for Research and Education in Agriculture, Nagoya University  

<p>Establishing sustainable food security in the midst of a natural environment that is changing on a global scale is one of the major challenges facing humanity. Particularly in tropical and subtropical regions, environmental problems such as desertification, unstable crop production due to drought, and loss of forests, as well as social unrest due to rapid population growth, are increasing. Many developing countries are located in these regions, and it is clear that urgent measures must be taken to solve these problems. Among them, the sub-Saharan region of Africa tends to have stagnant economic growth due to the economic burden of food imports to compensate for rapid population growth. We believe that we must do our utmost to build a sustainable agricultural system that utilizes limited resources in order to contribute to the development of agriculture in this harsh natural environment and economic crisis. The origin of rice cultivation in Africa dates back to 3500 years ago. Recently, the Africa Rice Center has developed interspecific hybrids, NERICAs, which are expected to contribute to food self-sufficiency in the region. The Japanese government and the Japan International Cooperation Agency have been supporting and contributing to the development of rice production in Africa. The author has been conducting various research projects on rice production with various international and domestic research institutes in the region for about 30 years. In this chapter, the history of Japan’s technical cooperation for rice development in Africa and the characteristics of the rice ecosystem will be explained. The functions and problems of interspecific hybrids, which have been developed recently and are being promoted throughout Africa, are also introduced. Furthermore, the characteristics and research results regarding African rice, a genetic resource unique to Africa, will be described. Finally, the future direction of rice cultivation in Africa is proposed by introducing examples of current efforts.</p>

DOI： 10.50907/jicad.20.0_13

Language：Japanese   Publisher：AIMS Agriculture and Food  

Direct seeding of rice (DSR) may give benefit in using water and labor more efficient and reduce production costs. This study purposes to investigate the character of the seeds, their early vigor traits, the growth and development of rice plants for developing DSR cultivar. The research was conducted in four stages: the measurement of the size of the seed, endosperm, and embryo; the germination test in the laboratory; seedling test using experimental pots; and testing the agronomic performance on transplanting and direct seeding methods in a plastic house. Seed material used eight breeding lines of IPB University and two released varieties. The results of study showed that each genotype had different characteristics of seed, endosperm, and embryo in both weight and area. Seed weight becomes the most dominant in the emergence of superior EV traits, whereas the more seed weight indicates faster radicle emergence and more weight of seedling. DSR method compared to transplanting showed performance such as taller plant, higher leaf area and photosynthesis rate at early growth stage, earlier heading time, and higher plant dry weight since early growth until 65 days old. The seed characters have positively correlation to dry weight of seedlings, number of leaves, leaf area, and canopy dry weight. We also found that higher area of endosperm and embryo significantly correlated to have faster plumule emergence, higher leaf area and plant height. Candidate genotypes for DSR would be further investigated in the field trial agronomically.

DOI： 10.3934/AGRFOOD.2022001

Scopus

Language：Japanese   Publisher：Applied and Environmental Soil Science  

The aim of this study was to determine the proper combination of nitrogen (N) fertilizer level and nitrogen fixing endophytic bacteria (NFEB) supplementation for the maximum grain yield of sesame cultivated in alluvial soil in dykes. The experiment followed a completely randomized block design with two factors. The first one was the levels of N fertilizer used, including 0, 50, 75, and 100% N of recommended fertilizer formula (RFF), and the other consisted of no bacteria applied, an individual strain of Enterobacter cloacae ASD-48 or E. cloacae ASD-21 applied, and their mixture, with 5 replicates. The results revealed that fertilizing with 100% N of RFF led to an enhancement of the plant height (16.8 cm), the chlorophyll a and b and their total content (6.45, 1.86, and 8.30 μg mL-1), the number of capsules per plant (7.22 capsules plant-1), the total N uptake (126.5 mg N pot-1), and the grain yield (9.08 g pot-1), in comparison to no N fertilizer applied. Supplementation of two NFRB strains enhanced the soilconcentrations of NH4+ and NO3-, the total N uptake, and the grain yield. The treatment fertilized with 75% N of RFF plus an individual NFEB strain or their bacterial mixture had equivalent total N uptake to that the treatment fertilized with 100% N of RFF had, 120.8-125.5 mg N pot-1 compared to 124.4 mg N pot-1. Regarding the sesame yield, with a reduction by 25-50% N of RFF plus ASD-48 and ASD-21, either individually or in mixture, it increased by 2.39-8.56%, compared to that in the treatment fertilized with 100% N of RFF.

DOI： 10.1155/2022/1972585

Scopus

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The cultivation period of cassava in Kagoshima, Japan, which belongs to the temperate zone, is limited by the low temperature in winter. To maximize productivity under this limited period, investigations were conducted on the gas exchange rate and production structure relating to light utilization in a plant community of cassava grown under different nitrogen fertilization conditions. Fertilization either at planting or three months after planting significantly increased stomatal conductance in the upper canopy and root dry weight compared to the control. In addition, the dry matter distribution to stem and root dry matter rate of initial fertilization treatment were significantly higher, and the dry matter distribution to root of the latter fertilization treatment tended to be higher than that of the control. However, light transmittance at 80 cm below the top of the canopy was almost the same as that at the ground surface, which was a common tendency among the treatments. In conclusion, it was revealed that the effects of fertilization on yield were mainly the increase in the gas exchange rate of individual leaves and the change of dry matter distribution rather than an improvement in light transmittance.

DOI： 10.3390/agronomy11102021

Scopus

Language：Japanese   Publisher：Digestive and Liver Disease  

Background: The clinical characteristics of IgG4-related sclerosing cholangitis (IgG4-SC) especially without autoimmune pancreatitis (AIP) have not been investigated in a large cohort. Aims: To clarify the clinical characteristics of IgG4-SC and IgG4-SC without AIP. Methods: We retrospectively reviewed imaging, serology, other organ involvement (OOI) and histology of 872 patients with IgG4-SC who participated in a Japanese nationwide survey in 2019, and compared these items between IgG4-SC with and without AIP. Results: AIP was present in 83.7% (730/872) of IgG4-SC. In IgG4-SC, bile duct wall thickening was observed on ultrasound (528/650; 81.2%), computed tomography (375/525; 71.4%) and magnetic resonance imaging or cholangiopancreatography (290/440; 65.9%). An elevated serum IgG4 level (≥ 135 mg/dL) was found in 88.0% (322/366). IgG4-related OOI other than AIP was observed in 25.2% (211/836). The proportion of females was significantly higher in IgG4-SC without AIP (28.9% vs. 20.1%; p = 0.025). Hilar stricture was the most common cholangiographic type in IgG4-SC without AIP (39/107; 36.4%).There were no significant differences between IgG4-SC with and without AIP in the rates of bile duct wall thickening, elevated serum IgG4 level, or IgG4-related OOI. Conclusions: The clinical characteristics of IgG4-SC was similar between IgG4-SC with and without AIP in a large cohort.

DOI： 10.1016/j.dld.2021.02.009

Scopus

Language：Japanese   Publishing type：Research paper (scientific journal)  

Flood and drought have been increasing due to global climate changes and these extreme water-related events often affect crop productions globally. This study aims to develop a growth simulation model that correspond to sequential soil water status by revealing morph-physiological related responses on the chili pepper (Capsicum spp.). Two experiments were conducted in a greenhouse and nine treatments were established between dry and waterlogged soil conditions by using a slope field with sand. Results showed leaf water potential and stomatal conductance decreased with increasing soil water stress level. On the other hand, chili pepper increased total chlorophyll content and decreased chlorophyll a/b ratio to compensate the redaction of the leaf area as a response to soil water stress. Moreover, high air vapor pressure deficit and solar radiation condition influenced their morph-physiological traits as environmental stress coupled with soil water stress. A multiple regression model for estimating shoot dry weight (SDW) using plant height (PH) and soil plant analysis development (SPAD) was developed (SDW = 0.131 PH + 0.047SPAD − 2.408). It showed a high coefficient of determination (R = 0.836). This model is certainly useful for estimating SDW under wide range soil water statuses and vapor pressure deficit conditions. 2 adj

DOI： 10.1016/j.scienta.2021.109943

Scopus

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI  

Flooding and drought are major causes of reductions in crop productivity. Root distribution indicates crop adaptation to water stress. Therefore, we aimed to identify crop roots response based on root distribution under various soil conditions. The root distribution of four crops-maize, millet, sorghum, and rice-was evaluated under continuous soil waterlogging (CSW), moderate soil moisture (MSM), and gradual soil drying (GSD) conditions. Roots extended largely to the shallow soil layer in CSW and grew longer to the deeper soil layer in GSD in maize and sorghum. GSD tended to promote the root and shoot biomass across soil moisture status regardless of the crop species. The change of specific root density in rice and millet was small compared with maize and sorghum between different soil moisture statuses. Crop response in shoot and root biomass to various soil moisture status was highest in maize and lowest in rice among the tested crops as per the regression coefficient. Thus, we describe different root distributions associated with crop plasticity, which signify root spread changes, depending on soil water conditions in different crop genotypes as well as root distributions that vary depending on crop adaptation from anaerobic to aerobic conditions.

DOI： 10.3390/agronomy11040708

Web of Science

Scopus

Language：Japanese   Publisher：IOP Conference Series: Earth and Environmental Science  

Salibu rice cultivation is one of the technological innovations to spur productivity or increase production. Salibu technology (modified ratoon) is a rice cultivation technology that utilizes rootstocks after harvest to produce shoots or tillers for nurturing. These shoots function as seeds in a transplanting system. Cutting treatment on the first generation of salibu crop started when the mother plant harvested at 132 days after sowing at 20 cm above the soil surface, and then re-cut seven days after harvest at 3-5 cm above the soil surface. Cutting treatment on the second generation of salibu crop started when the first generation of salibu crop harvested at 94 days. The results showed that the Batang Piaman variety has the best agronomic responses on the ratoon salibu system because the yield was 60% for the first generation of salibu and 62.5% for the second generation of salibu. Ketan Grendel variety the product was 70.5% for the first generation of salibu and 55% for the second generation of salibu.

DOI： 10.1088/1755-1315/694/1/012030

Scopus

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Other Link： https://www.cropj.com/nurrahma_15_1_2021_107_113.pdf

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Other Link： https://www.mdpi.com/2071-1050/13/2/670/htm

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

Other Link： https://www.ansinet.com/abstract.php?doi=ajcs.2021.1.8

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI  

Regulation of non-structural carbohydrates (NSCs) are important for plants in response to submergence. In this study, the difference in non-structural carbohydrates in relation with shoot elongation between Sub1A and non-Sub1A rice genotypes was investigated. Two rice genotypes, namely Inpari30 (Sub1A genotype) and IR72442 (non-Sub1A genotype), were submerged completely for 6 days and re-aerated by lowering water level up to stem base for 6 days of post submergence. In addition, non-submerged plants (control) was treated with water level up to stem base during the experiment. Photosynthesis rate decreased in both submerged Inpari30 and IR72442 genotypes 71% and 96% lower than their control, respectively. Submerged IR72442 declined Fv/Fm 15.6% lowest than its control and both control and submerged Inpari30. Investigation of the distribution of starch and soluble sugar content in plant organs suggested that shoot elongation of non-Sub1A genotype led to starch and sugar consumption that distributed faster to the new developed organ during submergence. In contrast, Sub1A genotype of Inpari30, which did not exhibit shoot elongation and showed slower NSCs distribution during submergence, performed better on post submergence by maintaining NSCs and distributing to the new developed organ faster than IR72442. These results suggest that Sub1A genotype managed elongation and NSCs during submergence more efficiently than non-Sub1A genotype.

DOI： 10.3390/su13020670

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：DE GRUYTER POLAND SP Z O O  

Drought is the main constraint for crop growth worldwide. Selenium reportedly plays an important role in improving plant tolerance to drought stress. In this study, two experiments were conducted to investigate the effects of foliar selenium application on the drought tolerance of sesame. Five selenium concentrations (0, 5, 10, 20, and 40 mg/L) were used in the first experiment. Water deficit was triggered 25 days after sowing. The application of 5 or 10 mg/L of selenium maintained the number of leaves and increased the number of capsules. However, higher concentrations induced necrosis. The second experiment aimed to study the effect of selenium concentrations (5 and 10 mg/L) and the number of applications (one to three times). Drought stress was triggered 50 days after sowing, and selenium was sprayed 50, 55, and 60 days after sowing. The results indicated that a one-time foliar selenium application of 5 mg/L was able to maintain the number of leaves and to increase proline accumulation, plant biomass, and grain weight per plant. This finding confirms that selenium can be applied to enhance sesame's tolerance to drought stress.

DOI： 10.1515/opag-2021-0222

Web of Science

Scopus

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

Other Link： http://article.sapub.org/10.5923.j.plant.20211101.01.html

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Open Agriculture  

Drought is the main constraint for crop growth worldwide. Selenium reportedly plays an important role in improving plant tolerance to drought stress. In this study, two experiments were conducted to investigate the effects of foliar selenium application on the drought tolerance of sesame. Five selenium concentrations (0, 5, 10, 20, and 40 mg/L) were used in the first experiment. Water deficit was triggered 25 days after sowing. The application of 5 or 10 mg/L of selenium maintained the number of leaves and increased the number of capsules. However, higher concentrations induced necrosis. The second experiment aimed to study the effect of selenium concentrations (5 and 10 mg/L) and the number of applications (one to three times). Drought stress was triggered 50 days after sowing, and selenium was sprayed 50, 55, and 60 days after sowing. The results indicated that a one-time foliar selenium application of 5 mg/L was able to maintain the number of leaves and to increase proline accumulation, plant biomass, and grain weight per plant. This finding confirms that selenium can be applied to enhance sesame’s tolerance to drought stress.

Other Link： https://www.degruyter.com/document/doi/10.1515/opag-2021-0222/html

Language：Japanese   Publishing type：Research paper (scientific journal)  

Flooding is one of the major abiotic stresses which accounts for considerable damage to plant growth and development and induces multiple morpho-physiological dysfunctions in many crop plants, including buckwheat. The present study aimed to elucidate the potential stage and duration of waterlogging treatment during the various stage that had the most severe effect on yield in common buckwheat (Fagopyrum esculentum cv. Harunoibuki). The plants were subjected to flooding stress during 3 days at ES, MS, and FS with 5 cm of water depth. The results showed that the plant height, SPAD (soil plant analysis development) value, chlorophyll fluorescence, root analysis (length, surface area, and volume), and dry weight were found to be influenced when plants were exposed to flooding stress at each stage. Here it was demonstrated that root parameters were more impaired by flooding stress than shoot parameters. The findings concluded that early growth stage was more sensitive regarding physiological characteristics (value of SPAD and chlorophyll fluorescence) and root morphology (root length, surface area, volume, and dry weight) under flooding stress in common buckwheat.

DOI： 10.1007/s12892-020-00044-7

Scopus

Language：Japanese   Publishing type：Research paper (scientific journal)  

Submergence is an environmental challenge for crop cultivation which causes physiological perturbation and yield loss. Tolerant genotypes are characterized by the ability to maintain physiological processes, especially photosynthesis, minimizing the negative effects of flooding stress. This experiment was aimed to examine the photosynthetic ability during submergence and a recovery period in rice variety of Inpari30 (carrying gene Sub1) compared to IR72442 (an elongation type) under control and submergence treatment. A randomized complete block design was employed in this experiment with three replications. The first factor was the environmental condition consisting of control and submergence. The second factor was rice varieties consisting of Inpari30 and IR72442. Fourteen-day-old seedlings were submerged under 35 cm of water depth for 6 days and re-aerated by lowering the water level up to the stem base for 6 days of recovery. Measurement of plant height, SPAD, Fv/Fm and photosynthetic rate were taken continuously from the same plant sample following the experimental stage. The results showed that shoot length increased significantly more in IR72442 than in the quiescent Inpari30. The noticeable decline was observed in the photosynthetic rate of both varieties during submergence with chlorophyll content and chlorophyll fluorescence (Fv/Fm) decreased more severely in IR72442 than in Inpari30. After flooding, Inpari30 adapted quickly to the aerobic environment, as shown by a recovery in Fv/Fm and accumulated dry weight more quickly than IR72442. We concluded that the Sub1 genotype of Inpari30 confers the ability to maintain maximum quantum yield of PSII under conditions of limiting gas exchange for photosynthesis for adapting post submergence.

DOI： 10.21475/ajcs.21.15.01.2889

Scopus

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.251.0_162

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.251.0_103

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.251.0_139

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.251.0_106

Language：English   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.251.0_102

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER INST MATHEMATICAL SCIENCES-AIMS  

Benefits of biochar application on environment conservation and agricultural production have been widely studied. However, few studies were focused on root development. The objective of this study covered root and shoot development, yield, and soil properties associated with exposure of Oryza glaberrima rice during the early reproductive stage to drought stress in rice-husk amended soil. The biochar was amended at a rate of 10.5 g pot(-1), equivalent to 3 ton ha(-1). Biochar-amended and non-amended plants were exposed to drought stress after the panicles had visibly emerged in all plant populations. Biochar application caused less restriction on root elongation, volume, and surface area during water stress conditions. Enhanced root development was primarily associated with improvement in water status and chemical properties in biochar-amended soil. Soil chemical properties improved, including increased soil pH, available P, cation exchange capacity, and exchangeable Mg. Under drought stress conditions, shoot growth was more sensitive than root growth, as indicated by the significant reduction of stem dry weight (SDW) and leaf dry weight (LDW). Fine roots in biochar-amended soil were longer than those in non-amended soil. In general, Biochar application enable the O. glaberrima rice to maintain yield under drought stress condition.

DOI： 10.3934/agrfood.2021043

Web of Science

Scopus

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

Other Link： https://www.cropj.com/iwatta_14_12_2020_1935_19141.pdf

Publishing type：Research paper (scientific journal)  

Chili pepper (Capsicum annuum L.) is a preferred vegetable by local farmers at a riparian wetland in Indonesia due to high market demand and its economic value. Chili pepper can be grown immediately after rice harvesting, concurrently with the early dry season. Three chili pepper varieties, namely Genie, Romario, and Laris were evaluated for their adaptability to drought condition. Drought treatment was imposed for 7 days until soil water potential was dropped to around −30 to −40 kPa. Morphological and photosynthetic traits were measured at pre-, during, and post-drought exposures. Growth analysis was calculated based on measured morphological traits. Results indicated that the number of leaves (NoL), total leaf area (TLA), total accumulated dry matter (TDM), and relative growth rate (RGR) were negatively affected by drought. Water content of shoot (SWC), leaf (LWC), and root (RWC) were significantly decreased during drought exposure; yet, able to fully recover at 7 days after drought treatment was terminated. Decrease in shoot root ratio (SRR) and leaf weight ratio (LWR); reversely, increase the root weight ratio (RWR) under drought condition, was not associated with enhancement of root growth. Rather, it was due to less negatively effect of drought on roots than on the above-ground organs. Simultaneously, chlorophyll fluorescence, LWC, stomatal conductance, transpiration and photosynthetic rates declined during drought exposure. However, 7 days after drought treatment was terminated, all traits were able to return to pre-drought levels. Among chili pepper varieties studied, Genie exhibited better overall performance than Laris and Romario did under drought stress condition.

DOI： 10.1016/j.aoas.2020.09.002

Scopus

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

Other Link： https://www.sciencedirect.com/science/article/pii/S0570178320300403?via%3Dihub

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI  

Seed priming refers to seed enhancement methods that stimulate seed metabolism. This study evaluated the genetic diversity of hydro priming efficacy in 27 different genotypes of rice under dry to wet soil moisture conditions. The genotypes included 21 genotypes of Oryza sativa, five genotypes of Oryza glaberrima, and one genotype of NERICA (New Rice for Africa). The treated rice seeds were sown in plastic boxes under four soil moisture conditions (5%, 10%, 15%, and 20% (w/w)). The genotypes were categorized into six groups based on growth parameters using hierarchical cluster analysis. Furthermore, emergence properties were investigated by using principal component analysis based on the mean emergence time of control and primed seeds. Seed priming enhanced growth performance under the moderate dry conditions of 10% and 15% soil moisture. Meanwhile, priming efficacy was low in water stress conditions of 5% and 20% soil moisture. There were wide‐ranging genotypic differences of priming efficacy under 20% soil moisture condition. Our findings indicate that the anaerobic‐tolerant genotypes tend to exhibit priming efficacy under high soil moisture conditions. Furthermore, one group included all upland genotypes of O. sativa. This group originally adapted to 10% and 15% of dry conditions, and seed priming improved their features greatly.

DOI： 10.3390/genes11090994

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PubMed

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Language：English  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (international conference proceedings)  

Flooding imposes a severe selection pressure on plants principally because excess water in their surroundings can deprive them of certain basic needs, notably of oxygen and of carbon dioxide and light for photosynthesis. It is one of the major abiotic influences on species' distribution and agricultural productivity world-wide. A cultivated species, O. glaberrima is origin from Africa that spread to floodplains area along river. Work to develop more tolerant crops or manage flood-prone environments more effectively is also included. Here, recent progress in elucidating the mechanisms determining tolerance versus intolerance to anaerobic stress caused by flooding in higher plants is discussed. This work integrates various specialized approaches ranging from morphology to physiology, and demonstrates how plant biology can be harnessed to improve stress tolerance in an important crop species. Materials and Methods: The research is conducted in various place of fields. As materials of rice and sugarcane, and chilli pepper are used in the experiments. Results and Discussion: We emphasize that Sub1A is not appropriate when selecting and breeding rice cultivars of O. glaberrima for resilience to longer-term submergence. Under these circumstances, a vigorous ethylene-mediated underwater elongation response by leaves is needed to return leaves to air-contact and full photosynthetic activity. Root aerenchyma is formed in waterlogged condition to on the genotype of sugarcane and oxygen in the air is supplied to the root system thorough aerenchyma. The supplied oxygen is used for root system respiration.

DOI： 10.1088/1755-1315/418/1/012080

Scopus

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER  

Soil drought occurrence during dry season has been the main constraint, besides prolonged flooding during rainy season, in increasing cropping intensity and rice productivity in tropical riparian wetland. Use of drought tolerant rice genotype might be a suitable option for overcoming such problem. This study focused on the effects of gradual soil drying during early vegetative growth stage on morphological and physiological traits of five Oryza glaberrima genotypes, namely RAM12, RAM14, RAM59, RAM97 and RAM101, and two Oryza sativa subsp japonica genotypes, i.e. Koshihikari and Minamihatamochi. The plants were subjected to 6 d of gradual soil drying condition from 15 days after transplanting (DAT) to 20 DAT, and were allowed to recover until 22 DAT. Gradual soil drying reduced plant growth as indicated by dry mass accumulation. Drought reduced stomatal conductance and increased leaf rolling score of all the genotypes. All the genotypes showed comparable response on stomatal conductance, but O. glaberrima genotypes performed higher in leaf rolling recovery. Meanwhile, O. sativa genotypes decreased total leaf area and specific leaf area, but increased specific leaf weight in order to avoid further damages due to drought stress. Drought tolerance mechanisms in RAM101, RAM12, RAM59 and RAM14 were associated with leaf morpho-physiological responses, root traits and dry biomass accumulation.

DOI： 10.1016/j.rsci.2019.12.007

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Publishing type：Research paper (scientific journal)  

Straw from Bangladeshi indigenous rice (Oryza sativa L. ssp. indica) variety ‘Goria’ was incorporated into a gray soil to observe the phytotoxic effects on Echinochloa oryzicola. The residues of ‘Goria’ caused inhibition on the growth and dry weight of E. oryzicola. The rate of ‘Goria’ straw incorporation was sequentially evaluated to observe autotoxicity in the cultivation of the same rice variety. An improvement was found on the growth and yield parameters of rice due to the straw incorporation into the soil. Aqueous methanol extracts of ‘Goria’ straw inhibited the seedling growth of Lepidium sativum L. and E. oryzicola, which suggested that this variety might contain phytotoxic substance(s). Two biologically active compounds, (-)-loliolide and 3β-hydroxy-5α,6α-epoxy-7megastigmen-9-one, were isolated using several chromatographic steps. The phytotoxic potential of these two compounds was assayed in vitro on the seedling growth of test flora to validate it. The inhibitory activity of 3β-hydroxy-5α,6α-epoxy-7-megastigmen-9-one was greater than that of (-)-loliolide, as demonstrated by comparison of the I values. However, the two compounds synergistically suppressed the growth of L. sativum and E. oryzicola more strongly than the individual compounds. The results suggest that incorporation of allelopathic rice Goria-straw could help suppress E. oryzicola in rice to achieve non-herbicidal weed control. 50

DOI： 10.15666/aeer/1804_55475560

Scopus

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.249.0_111

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.249.0_20

Publisher：日本作物学会  

DOI： 10.14829/jcsproc.249.0_102

Publishing type：Research paper (scientific journal)  

Spikelet sterility induced by soil moisture stress during reproductive development greatly limits grain yield in upland rice. This study aimed to elucidate differences in responses to soil moisture stress for pollen development, pollination and fertilization among upland rice cultivars. A greenhouse experiment with a split-plot design was performed for five different soil moisture treatments (T1 to T5) as the main plots and three cultivars (NERICA 1, NERICA 4 and Yumenohatamochi) as subplots, each with three replicates. Plants in pots were grown under well-watered condition (T1) and various moisture stress conditions: moderate at the booting stage (T2), severe at the booting stage (T3), moderate at the flowering stage (T4) or severe at the flowering stage (T5). During the 9-day stress period, soil moisture was maintained at -10 to -20 kPa for moderate moisture stress or -20 to -49 kPa for severe moisture stress under controlled irrigation. NERICA 1 had fewer differentiated microspores and developed pollen grains in T2 and T3 and showed poorer anther dehiscence and fewer pollen grains on the stigma than did NERICA 4 and Yumenohatamochi. NERICA 4 showed a lower percentage of basal dehiscence in T4 and T5, causing fewer pollen grains to be deposited on the stigma than for NERICA 1 and Yumenohatamochi. The results indicate that the highly sensitive process of fertilization are pollen development in NERICA 1 and pollination in NERICA 4 under soil moisture stress.

DOI： 10.21475/ajcs.20.14.12.2774

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Chili pepper is frequently grown by local farmers at riparian wetland during dry season in Indonesia. However, during the last decade, unpredictable distribution and intensity of rainfall have increasingly threatened chili pepper production at the wetlands due to untimely water-saturated rhizosphere (WSR) occurrences. WSR is a condition when all pores within root zone were filled with water. This condition can be simulated by adding water into growing substrate until a thin layer of water was visible above substrate surface. Two Indonesian varieties (Laris and Romario) and one Japanese variety (Takanotsume) were used in this study. Aim of this study was to evaluate morpho-physiological effects of short-term (4 days) WSR exposure in chili pepper. Results of this study revealed that roots suffered more than aerial organs as indicated by the increase of shoot/root ratio from 4.56 at pre-exposure to 7.03 at end of the exposure. Total leaf area significantly reduced since larger older leaves were replaced by newly developed smaller leaves. Relative water content (RWC) in all organs was decreased, but did not reach a detrimental level. Leaf RWC was decreased from 83.6% at pre-exposure to 77.8% after the exposure; however, leaf RWC was able to rebound to 81.5% after 7 days of recovery. Photosynthetic and transpiration rates sharply decreased, associated with decrease in stomatal conductance during WSR exposure. Chlorophyll fluorescence also sharply declined. Gas exchange parameters did not significantly recover after 7 days of recovery in all varieties. Meanwhile, SPAD values were not affected by WSR exposure.

DOI： 10.21475/ajcs.19.13.11.p2046

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Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing Ltd  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER INDIA  

© 2019, Society for Sugar Research &amp; Promotion. As a step toward breeding cultivars with tolerance to chilling stress, phenological changes in chlorophyll content (SPAD index) and its fluorescence (Fv/Fm) were investigated under over-wintering conditions using different sugarcane clones. A leading commercial cultivar in Japan, NiF8, and two interspecific lines, KY11-6114 and KY08-1200, were tested in this study. Daily minimum temperature decreased gradually with the advance of winter, and the lowest temperature of 1.2 °C was recorded in January. Although the temperature increased toward spring season, it remained below 10 °C until the end of experiment. Stem elongations in KY11-6114 and KY08-1200 during winter were significantly greater than in NiF8. The decrease in SPAD index was calculated from the difference between the beginning of winter and each measuring time. KY08-1200 and KY11-6114, with longer stem elongation, had a smaller decrease in SPAD index than NiF8 under over-wintering conditions. The Fv/Fm of all three clones decreased in January when the lowest temperature was recorded and recovered toward spring. Among three clones, KY08-1200 was less affected by chilling stress and presented a higher value of Fv/Fm up to the end of experiment. Considering these results, we concluded that the decreased chlorophyll content measured by the SPAD index was a simple indicator for screening chilling-tolerant clones.

DOI： 10.1007/s12355-018-0693-0

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English  

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. The phytotoxic effects of two allelochemicals (trans-cinnamic acid and syringaldehyde) at different concentrations (1000, 100, 10, and 1 µM) on seed germination, seedling growth, and physiological and biochemical changes of Echinochloa crus-galli L. were tested by comparison to a commercial herbicide ‘Nominee’ (that is, 100 g/L bispyribac-sodium). trans-Cinnamic acid and the herbicide inhibited seed germination completely at 100 µM, whereas for syringaldehyde, complete inhibition required 1000 µM. However, with 100 µM syringaldehyde, the seed germination of the test species was 53% of the control. Allelochemicals and the herbicide delayed seed germination and significantly affected the speed of germination index (S), speed of cumulative germination index (AS), and coefficient of germination rate (CRG). The roots were more affected when nutrients were not added to the growth bioassay. In general, with the increasing concentration of allelochemicals from 100 to 1000 µM, the inhibitory effects increased. Via microscopy analysis, we found leaf blade wilting and necrosis at concentrations above 100 µM in allelochemical-treated plants. Roots of E. crus-galli treated with 1000 µM allelochemicals had black points on root nodes but had no root hairs. The anatomy of roots treated with allelochemicals (1000 µM) showed contraction or reduction of root pith cells as well as fewer and larger vacuoles compared to the control. The allelochemicals also showed remarkable effects on seedling growth, SPAD index, chlorophyll content, and free proline content in a pot culture bioassay, indicating that trans-cinnamic acid and syringaldehyde are potent inhibitors of E. crus-galli growth and can be developed as herbicides for future weed management strategies.

DOI： 10.1007/s00344-018-9865-0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

© 2019 Weed Science Society of Japan This study aimed to identify the potential allelopathic indigenous rice (Oryza sativa L. ssp. indica) varieties from Bangladesh using a performance study in a weed-infested field and to assess the extent of allelopathic interference relative to resource competition in a glasshouse experiment. Six varieties – namely, “Boterswar,” “Goria,” “Biron” and “Kartiksail” as the most allelopathic, “Hashikolmi” as weakly allelopathic and “Holoi” as nonallelopathic – were raised following a nonweed control method. The infestation levels of weed species were calculated using Simpson&#039;s Diversity Index (SDI), which ranged from 0.2 to 0.56. However, a significant correlation coefficient (0.87, P &lt; 0.001) was obtained from these field data compared with the root inhibition percentage from the laboratory bioassay, and the “Boterswar” variety was the most allelopathic. The interactions between the allelopathic variety “Boterswar,” weakly allelopathic variety “Hashikolmi” and Echinochloa oryzicola via a target (rice)-adjacent (E. oryzicola) cogrowth culture were determined in a hydroponic arrangement. The relative competitive intensity (RCI) and the relative neighbor effect (RNE) values showed that the crop–weed interaction was facilitation for “Boterswar” and competition for “Hashikolmi” and E. oryzicola in rice/E. oryzicola cogrowth cultures. The allelopathic effects of “Boterswar” were much higher than the resource competition in rice/E. oryzicola cogrowth cultures. The converse was observed for “Hashikolmi.” Moreover, the mineral content of E. oryzicola was severely affected by “Boterswar”/E. oryzicola cogrowth cultures’ exudate solution. Therefore, the allelopathic potential of “Boterswar” variety might be useful for developing the weed-suppressing capacity of rice, which will likely have a significant influence on paddy weed control.

DOI： 10.1111/wbm.12174

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Deficiency of available phosphorous (P) in soil is one of the major factors that limit plant growth and yield. Microorganisms play an important role to improving available P status in soil by solubilization. Although phosphate solubilizing mechanism is not clearly understood, organic acid production seems to be the main mechanism of P solubilizing. Therefore, present study evaluated the organic acid production potentials of 16 P solubilizing fungal strains (2 Aspergillus floccosus, 3 Aspergillus niger, 2 Aspergillus niveus, 2 Penicillium oxalicum, 5 Penicillium spp. and 2 Talaromyces pinophilus isolates) isolated from soils in Okinawa, Japan to select outstanding strains that could facilitate the P solubilization process. Results revealed that both type and quantity of microbial organic acids production depend on the P sources and fungal strains. The highest quantity of organic acids was found when Ca (PO ) was used as substrate followed by FePO and AlPO . Based on the organic acids production potential, A. niger (SI-12URAgr) considered as outstanding P solubilizing fungi regardless of substrates followed P. oxalicum (SI-6URAgr, SI-16URAgr) and A. niger (SI-10URAgr). These strains could have great potential as promising bioresource for efficient P utilization in agricultural production. 3 4 2 4 4

DOI： 10.15666/aeer/1706_1519115201

Scopus

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_71

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_123

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_29

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.248.0_115

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_30

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_52

Publisher：Applied Ecology and Environmental Research  

DOI： 10.15666/aeer/1704_91459157

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

© 2018 Southern Cross Publishing-Australia. Yellow velvetleaf (Limnocharis flava (L.) Buchenau) is an edible plant commonly found at rice fields in tropical riparian wetlands. At present, young leaves and flower buds of L. flava are commonly gathered from rice field during off- growing season. This plant is rarely cultivated. Research was conducted for evaluating L. flava response to (1) different water regimes, i.e. flooding, water saturated soil, and shallow water table, for mirroring water behavior at riparian ecosystem; and (2) NPK application rates up to 6 g/plant. Pots used do not have bottom drainage hole; instead four side holes were drilled on each pot at height matching to water level treatments. Primary growth traits, leaf growth analysis, and chlorophyll concentration index were measured for evaluating adaptability of the velvetleaf plant to varying water levels and responsiveness to NPK fertilizer. Results of this research indicated that L. flava was well-adapted to all water regimes varied from 3 cm below to 3 cm above soil surface but it grew better under flooded condition at depth of 3 cm during vegetative growth stage. The L. flava positively responded to NPK fertilizer application at rate of 6.0 g/plant, both during vegetative and reproductive growth stages. Increase in leaf area was driven by leaf water content but the increase in leaf area was followed by decrease in specific leaf weight.

DOI： 10.21475/ajcs.18.12.11.p1451

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese  

CiNii Books

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：International Allelopathy Foundation  

Aqueous methanol extracts of the Bangladesh indigenous rice (Oryza sativa L.ssp. indica) variety „Boterswar‟ inhibited the germination and seedling growth of Lepidium sativum L. and Echinochloa crus-galli L. Beauv which suggested that this variety may contain phytotoxic substance(s). Four biologically active compounds, syringaldehyde (4-hydroxy-3,5-dimethoxybenzaldehyde), (-) loliolide, 3β-hydroxy-5α,6α-epoxy-7-megastigmen-9-one and 3-hydroxy-β-ionone, were isolated from the ethyl acetate phase using several chromatographic steps. The chemical structures of the compounds were determined through electrospray ionization and spectroscopic analyses. The biological activity of these compounds showed that concentration &gt
10 μM significantly inhibited the root and shoot growth of E. crus-galli seedlings, and the I50 (50% growth inhibition) values ranged from 16.03 to 27.23 μM and 23.94 to 75.49 μM for root and shoot growth, respectively. The four compounds synergistically suppressed the growth of E. crus-galli more strongly than the individual compounds. Thus, the indigenous rice „Boterswar‟ has potential use for weed management and this indigenous variety could be used to develop a new commercial rice variety that may suppress weeds.

DOI： 10.26651/allelo.j./2018-43-1-1127

Scopus

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.245.0_96

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society of Breeding  

Improvement of resistance against rice bacterial blight (BB) disease is an important breeding strategy in breeding programs across the world, especially in Africa and southern Asia where BB is more prevalent. This report describes a high-resolution map and characterization of xa42 at XA42 locus, a rice BB resistance gene in XM14, a mutant line originating from IR24. The candidate gene region was narrowed down from 582 kb, which had been obtained in our previous study, to 57 kb. XM14 shows brown spots in its leaves like lesion mimic mutants. This line also shows a shorter stature than the original cultivar IR24. In XA42 gene segregating populations, homozygotes of xa42 allele were consistently resistant to the six Japanese Xanthomonas oryzae pv. oryzae races used for this study. They also showed brown spots and markedly short stature compared with the other genotypes, suggesting that xa42 gene exhibits pleiotropic effects.

DOI： 10.1270/jsbbs.17094

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PubMed

Publishing type：Research paper (scientific journal)   Publisher：Scientific Research Publishing, Inc.  

DOI： 10.4236/ajps.2018.911157

Other Link： https://www.scirp.org/xml/87864.xml

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

River floodplains are potential land resources to extend rice cultivation areas, most of which are not currently used for farming in West Africa. The major constraints that limit expansion of crop production in floodplain areas include difficulties of water management and lack of access to tractor services for land preparation at the appropriate timing for planting. However, there have been no field experiments to demonstrate the potential of rice cultivation in the floodplain ecosystems in West Africa. The objective of this study was to determine rice productivity and the responses to various fertilizer applications on different topographical positions within floodplain ecosystems. Three years of field experiments were conducted in no-till and no-bond conditions in various topographical positions including flood-prone areas with no farming history near back-swamps and conventional farmlands in the middle to upper slopes along a transect away from the White Volta River. The effects of different combinations of S, P and K fertilizer were evaluated with a constant rate of 60 kg N ha(-1) applied as urea or ammonium sulfate. Rainfall varied widely, with heavy rainfall during the initial growth stage in 2012, a long dry spell during the middle stage in 2013, and consistent rainfall in 2014. Both grain yields and responses to N application tended to increase at lower elevations and near the river, benefiting from the carbon and clay-rich soils and moisture availability, except when a submergence stress suppressed grain yield in the lowest field in 2012. The yield response was amplified with S application. On average, application of S resulted in an increase of agronomic N use efficiency from 13.4 to 22.8 kg grain per kg N applied. The effect of N and S applications were particularly large in the unutilized lowlands that produced the highest average yields ranging from 3.21 to 4.00 t ha(-1), compared to yields ranging between 0.38 and 1.40 t ha(-1) achieved on conventional farmlands. Our results clearly showed empirical evidence of high productivity and high N use efficiency for rice particularly with S application in the currently unutilized floodplain areas under no-till and no-bond rainfed conditions. Although the risk of reduced yields due to complete submergence exists, cultivation of rice in productive floodplain areas offers good opportunities to increase rice production in West Africa.

DOI： 10.1016/j.fcr.2017.06.030

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：CROP SCIENCE SOC AMER  

Submergence-tolerant rice (Oryza sativa L.) cultivars, including FR13A, retain green leaves for a longer duration than susceptible lines during submergence and exhibit prompt readaptation to the aerial environment after desubmergence. This study clarified the physiological mechanism responsible through the chlorophyll breakdown and photodamage in submerged rice leaves, as indicated by decrease in the maximal quantum yield of photosystem II (Fv/Fm). The ethylene-releasing agent ethephon was used to evaluate the effect of ethylene on chlorophyll breakdown and plant growth. FR13A (submergence-tolerant) and IR72442-6B-3-2-1-1 (submergence-susceptible), either treated with ethephon for 3 d before submergence or untreated, were submerged for 14 d. During submergence, the chlorophyll contents and Fv/Fm in the upper fully expanded leaf (fifth leaf) decreased earlier in IR72442 than in FR13A. The ethephon treatment accelerated the reduction of the Fv/Fm in the submerged fifth leaf of FR13A during submergence and inhibited recovery after desubmergence. The ethephon treatment reduced shoot biomass accumulation during and after submergence but had no effect on underwater shoot elongation in either cultivar. Therefore, photodamage was inhibited and high chlorophyll content was maintained in the submergence-tolerant cultivar during submergence. The negative effects of ethylene in response to ethephon may be mediated by other mechanisms and not by an increase in shoot elongation.

DOI： 10.2135/cropsci2016.10.0884

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN INT RESEARCH CENTER AGRICULTURAL SCIENCES  

This study aimed to identify suitable areas for rice cultivation by evaluating the soil characteristics of underdeveloped land in Sub-Saharan Africa. Two transect lines were set on the Zaw floodplain (ZFP) along the White Volta River in the Northern Region of Ghana for a detailed survey on land types and soil sampling. Land types identified along the transect lines were upland (U), lowland grass (Lg), lowland shallow swamp (Lss), and lowland deep swamp (Lds). The soil texture for U, Lg, and Lss was classified as silt loam (SiL), while Lds was classified as silty clay loam (SiCL). Soil pH (H2O) was above 6 for U and Lg, and below 6 for Lss and Lds. Extractable S and available Zn were significantly greater in Lds than in other land types. Available Cu, Mn, Ni, and total nitrogen (T-N) were significantly lower in U, and total carbon (T-C) was significantly greater in Lds than in other land types. Factor analysis indicated that Lds had better soil fertility and sulfur availability than other land types. However, it seemed unsuitable for rice production due to deep water depth during the rainy season. Although Lss seemed to be relatively less suitable than Lds due to low soil fertility and low sulfur availability, the water depth in Lss was not as deep as in Lds. Access to a water source was easier in Lss than in Lg; thus, the Lss land type was considered comparatively suitable land for rice production in the study area. Nevertheless, the result implies that soil fertility and sulfur could be constraints, thereby requiring the proper application of fertilizer.

DOI： 10.6090/jarq.51.77

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Publisher：Japanese Society for Tropical Agriculture  

DOI： 10.11248/nettai.10.18

Language：Japanese   Publisher：Japanese Society for Tropical Agriculture  

DOI： 10.11248/nettai.10.36

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)   Publisher：BRAWIJAYA UNIV, FAC AGRICULTURE  

Rice (Oryza sativa L.) is largely cultivated in lowland area that vulnerable to flood occurrence. Root supposed to play an important role on rice tolerance to submergence stress. An experiment which conducted from January to May 2014 in Cikarawang Field Laboratory, Darmaga, Bogor, West Java aimed to study the role of root distribution on rice submergence tolerant. The experiment used Split Plot design replicated three times, with the depth of submergence as main plot and rice variety as subplot. The main plot consisted of water depth of 5 (optimum), 50, 60 and 80 cm from soil surface. The subplot consisted of four rice varieties, namely Ciherang, Inpari 30 (Ciherang Sub1), Indragiri and Margasari. Each plant was planted in a root box (30 cm x 40 cm x 5 cm) which put into container (67 cm x 47 cm x 42 cm) and placed into the pond with water depth as treatment. Submergence started when the plant was 39 Days After Seeding (DAS) for ten days. Observation conducted after the submergence stopped (49 DAS). Result showed that submergence retarded plant growth, root distribution and increase root damage for all rice varieties with the biggest effect on susceptible varieties.

DOI： 10.17503/agrivita.v39i2.949

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

A series of experiments was conducted in the laboratory and greenhouse of the Subtropical Field Science Center, University of the Ryukyus, Japan, from April to October 2015 to assess the allelopathic potential of 50 indigenous Bangladeshi rice varieties by using the donor-receiver bioassay, equal compartment agar method (ECAM), plant residue extract method and pot culture method. Lettuce (Lactuca sativa L.), cress (Lepidium sativum L.), radish (Raphanus sativus L.), barnyard grass (Echinochloa crus-galli L. Beauv.) and jungle rice (Echinochloa colona L.) were used as the test plants. The highest inhibition effect was given by Boterswar, while the stimulating effect was given by Kartikbalam and Panbira in the donor-receiver bioassay and ECAM tests. Boterswar, Goria, Biron and Kartiksail were selected as the highest allelopathic-potential varieties by the donor-receiver bioassay and ECAM. In the methanol extract test, Boterswar gave the strongest inhibitory effect on both barnyard grass and jungle rice, while Kartiksail gave the highest inhibitory effect on the jungle rice shoot. The growth parameters and total dry matter of barnyard grass in the greenhouse pot experiment were significantly reduced as a result of the application of aqueous extracts of the selected rice varieties, which was similar to the results of the laboratory experiments. The varieties of Boterswar, Goria, Biron and Kartiksail were selected as the most allelopathic among the 50 indigenous Bangladeshi rice varieties. These rice varieties could be used for the isolation and identification of allelochemicals and to further develop new varieties that are tolerant to weeds.

DOI： 10.1111/wbm.12103

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Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE SOC BREEDING  

Bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo) is a chief factor limiting rice productivity worldwide. XM14, a rice mutant line resistant to Xoo, has been obtained by treating IR24, which is susceptible to six Philippine Xoo races and six Japanese Xoo races, with N-methyl-N-nitrosourea. XM14 showed resistance to six Japanese Xoo races. The F-2 population from XM14 x IR24 clearly showed 1 resistant : 3 susceptible segregation, suggesting control of resistance by a recessive gene. The approximate chromosomal location of the resistance gene was determined using 10 plants with shortest lesion length in the F-2 population from XM14 x Koshihikari, which is susceptible to Japanese Xoo races. DNA marker-assisted analysis revealed that the gene was located on chromosome 3. IAS16 line carries IR24 genetic background with a Japonica cultivar Asominori segment of chromosome 3, on which the resistance gene locus was thought to be located. The F-2 population from IAS16 x XM14 showed a discrete distribution. Linkage analysis indicated that the gene is located around the centromeric region. The resistance gene in XM14 was a new gene, named X2142. This gene is expected to be useful for resistance breeding programs and for genetic analysis of Xoo resistance.

DOI： 10.1270/jsbbs.16062

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PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

West Africa has large areas of river floodplains, most of which are not currently used for farmland. Rice (Oryza spp.) is a promising crop for farming in floodplains because of its high adaptability to a wide range of water environments. On the other hand, there is great variation in soil fertility and water availability even in a small area within a floodplain. Hence, we evaluated 27 rice genotypes in four fields in three years in a floodplain of the Northern Region of Ghana to investigate genotype x environment (G x E) interactions for rice yield and to identify stable, high-yielding genotypes. The genotypes consisted of a sativa, O. glaberrima and New Rice for Africa (NERICA), and many were selected for their reported submergence resistance because of the anticipated submergence damage in the floodplain. There were large variations in yield, which ranged from 0.14 to 5.35 t ha(-1) depending on the location within a floodplain, genotype and year, and there were significant genotype, environment and G x E interaction effects on yield, accounting for 24.8%, 20.2%, and 28.2%, respectively, of the total variation. The results suggested that selection of suitable location with high soil fertility and low risk of submergence is necessary to achieve high yield in a floodplain. In addition, early sowing would be effective high-yielding crop management, which reduced the risk of submergence-induced damage just after sowing and secured sufficient growth duration to achieve high yield. Genotype IR42 showed the highest average yield among environments, but its yield stability was low. On the other hand, several genotypes including Amankwatia, a local aromatic cultivar adapted to irrigated and lowland environments, and IRBL9-W[RL], a blast-tolerant variety containing the Sub1 gene for submergence tolerance, showed high, stable yield. To put these results to practical use in other floodplain areas in West Africa, physiological mechanisms causing G x E interaction for rice yield should be further studied. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.eja.2015.11.014

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Tropical Agriculture  

Two Indonesian rice cultivars were examined for growth characteristics under several durations of submergence consisting of 0 (control), 3, 5, 7, and 10 days. Rice seedlings were first submerged into a 45 cm water depth and then the water level remained constant, allowing some parts of the leaves to appear from the water surface during the treatments which resembled the actual flash flooding conditions in the field. Results showed that the change of the relative growth rate (RGR) in both cultivars was more attributed to the net assimilation rate (NAR) alteration compared to the leaf area ratio (LAR). The relationship between NAR and specific leaf area (SLA) was also investigated resulting in a significant negative correlation between these two variables where NAR increased by the thickening of the leaf blade. 1R Dadahup then was found to show a higher ability to survive and grow during a longer periods of flash flooding, compared to Ciherang, based on the minimal sheath elongation under submergence and positive response in both SLA and the relative tillering rate (RTR).

DOI： 10.11248/jsta.60.40

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

We investigated the morpho-physiological traits of rice (Oryza sativa L.) during the germination and post-germination phases to explore avoidance of hypoxic conditions. We compared four lines selected for anaerobic germination (AG lines) with the variety IR42. The germination capacity of AG lines was higher than that of IR42. The germination percentages and coleoptile elongation differed among the four AG lines; IR06F459 showed the fastest germination and rapid coleoptile elongation. The coleoptiles of IR06F459 were significantly longer than those of IR42. The a-amylase activity in germinating seeds was significantly higher in IR06F459 than in IR42. At 2 days after sowing, the sucrose and glucose concentrations in germinating seeds were higher in IR06F459 than in IR42. These results show that IR06F459, an AG line with a long coleoptile, has high a-amylase activity and high sucrose and glucose concentrations in germinating seeds. These attributes partly explain its vigorous germination and coleoptile growth under hypoxic conditions.

DOI： 10.1626/pps.18.471

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Scopus

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：AKADEMIAI KIADO RT  

To identify the adaptive traits responsible for flooding tolerance during the initial growth stages of rice, dry seeds of 53 contrasting genotypes were sown in soil and watered normally (control) or submerged with 10 cm of water for 17 days. Subsequently, the plants were kept under normal rice cultivation conditions for a further 7 days. Cluster analysis showed that 53 genotypes were divided into three groups based on emergence date, percentage of plants reaching the water's surface, maximum coleoptile length, shoot elongation rate during submergence and increases in shoot dry weight after de-submergence. Twelve genotypes were placed in cluster 1 and characterized by fast emergence, rapid coleoptile elongation, and vigorous shoot growth under control and submergence conditions. The genotypes in cluster 1 attained also a higher increase in shoot dry weight at different time of submergence and de-submergence than the genotypes in clusters 2 and 3. A significant correlation was observed between the increase in shoot dry weight and traits related with fast and vigorous shoot elongation and coleoptile. In conclusion, flooding tolerance during initial growth stages were mainly due to major submergence avoidance or escape mechanisms, and crop establishment of direct-seeded rice in flood-prone areas is accomplished by harnessing reserves for fast shoot elongation.

DOI： 10.1556/0806.43.2015.005

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Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：日本作物学会  

DOI： 10.1626/jcs.84.215

CiNii Books

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：Japanese  

J-GLOBAL

Language：Japanese   Publisher：The Weed Science Society of Japan  

Vegetation survey and cultivation experiments were conducted to investigate recovery and survival ability of <i>Plantago asiatica</i> for shoot removal by mowing at the paddy rice field levees. At four paddy rice field levees in Atsugi, Kanagawa Pref., populations of <i>P.</i> <i>asiatica</i> were mainly comprised of overwintering plants. Plant density of <i>P. asiatica</i> was maintained almost less than 300/m² throughout year, however, temporally increased with seedling emergence from June to August. Prematured inflorescences were totally removed by each mowing during summer and seed shattering occurred after final mowing in November. Performance of un-cut plants which sowed in the previous September, following April and June were compared to the cut plants with cut in frequency of the paddy rice field levee. As results, overwintering plants sowed in the previous September developed a similar number of leaves to the un-cut plants. However, they slightly reduced their shoot and root dry matter weight compared to the un-cut plants. On the other hand, plants sowed in April and July markedly decreased their leaf number as well as dry weight of shoot and root in comparison with un-cut plants. In addition, though the plants sowed in the previous September were removed in next June, seeds in premature capsules of those plants exhibited high germination percentage (88%). It became clear that seed of <i>P. asiatica</i> could germinate before shattering and regrowth ability after shoot removal of overwintered plants were high. These factors are considered to confer on <i>P. asiatica</i> to persist in paddy field levees.

DOI： 10.3719/weed.59.1

CiNii Books

J-GLOBAL

Other Link： https://agriknowledge.affrc.go.jp/RN/2010872278

Authorship：Corresponding author   Publishing type：Research paper (scientific journal)  

Identification of adaptive traits associated with flash flooding tolerance during the initial growth stages is one approach to enhance seedling establishment in direct-seeded rice. To identify these traits, dry seeds of 53 contrasting genotypes were sown in soil and watered normally (control) or submerged with 10 cm of water for 17 days. Subsequently, the plants kept under normal rice cultivation conditions for a further 7 days. Among these genotypes, nine lines had been developed for anaerobic germination and submergence tolerance (AG + Sub1) by IRRI. The length of coleoptile and mesocotyl were measured at different times of submergence period. Length and dry weight of shoot and root were measured during submergence and recovery periods. Emergence date and percentage of plants reaching the floodwater surface were monitored during submergence period. The results showed that tested genotypes were classified into four clusters based on coleoptile and mesocotyl lengths at different times of submergence period using Ward'soleoptilemethodandmesocotyl. TheofIR06F561c genotype that placed individually in cluster 4 and AG + Sub1 lines in cluster 2 elongated more rapidly than other genotypes under control and submerged treatments. Rapid elongation of coleoptile under submergence conditions was significantly correlated with the rapid seed emergence and the percentage of plant reached the floodwater surface. Shoot dry weight during recovery period was significantly correlated with the traits of fast seed emergence, rapid coleoptile elongation and vigorous shoot growth under submergence conditions. In conclusion, the AG + Sub1 lines (IR06F561) were identified having adaptive traits that contribute to flash flooding tolerance during emergence and early seedling growth stages.

Scopus

Publishing type：Research paper (scientific journal)   Publisher：Scientific Research Publishing, Inc.  

DOI： 10.4236/jwarp.2014.614121

Other Link： http://www.scirp.org/journal/doi.aspx?DOI=10.4236/jwarp.2014.614121

Language：Japanese   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：Japanese   Publisher：日本農学図書館協議会  

CiNii Books

J-GLOBAL

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

An understanding of the spatial variation in soil fertility is fundamental for extending rice cultivation and developing appropriate management practices in currently under-utilized floodplain ecosystem of West Africa. The spatial patterns in the soil total carbon (TC) contents were analyzed using a Quickbird imagery, a global digital elevation model (ASTER-GDEM) and ArcView GIS functions for a White Volta floodplain of northern Ghana. An irrigated pot experiment was then conducted to relate rice biomass production to the spatial TC distribution and to identify deficient nutrients using different fertilizer treatments.The TC contents showed great variability (2.0-40.2 g kg(-1)) in a lognormal distribution, and the values were logarithmically increased with the proximity to reservoirs, consisting of a main river, back-swamps and ponds. The spatial pattern in the TC contents corresponded to the length of the waterlogging period during the rainy season, which was also logarithmically increased with the proximity to reservoirs, as estimated from the time-series satellite images. The corresponding patterns indicated that the spatio-temporal hydrological variable was a principal factor for the variance in the soil TC contents. Regarding the pot experiment, the amounts of soil mineralizable nitrogen were in accordance with the TC contents and correlated linearly with the plant N uptakes. However, dry matter production was scarcely relevant to the N-supplying capacity of the soils. Limited S concentrations in the plant tissues and a significant response to S application indicated that an inherent S deficiency restricted the dry matter production. NPK application without S increased only the N concentration and N:S concentration ratio in the plant tissues but not the biomass production.The high N-supplying capacity of the soil was related to the seasonal flooding, and the productive land areas for rice cultivation in both indigenous N and water availability were quantitatively predicted as a logarithmic function of the distance to reservoirs. Appropriate S supplementation would be required to utilize effectively the local N supply for rice biomass production in this under-utilized floodplain ecosystem. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fcr.2012.11.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

DOI： 10.1016/j.fcr.2013.08.015

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Flooding imposes severe selection pressure on plants, principally because excess water in their surroundings deprives the plants certain basic resources such as oxygen, carbon dioxide, and light for photosynthesis. In recent years, reports of damage caused by flooding to rice plants have increased concomitantly with the expansion of rainfed lowland rice cultivation throughout the world. Strong submergence-induced elongation, a common escape mechanism, helps submerged individuals regain and retain contact with the aerobic environment. This study analyzed physiological mechanisms of escape from complete submergence by evaluating photosynthesis, photochemical reaction, and plant behavior during and after submergence in Oryza glaberrima Steud. Partially submerged plants were unaffected by excess water because their photosynthetic rate was maintained during and after submergence. Escape mechanisms, when under complete submergence, restrain shoot elongation per shoot dry weight per day during submergence (shoot elongation index). Our results demonstrate that the leaf area and shoot biomass of the submerged plants during submergence affects their post-submergence photosynthetic rate and the PSII maximum efficiency to some degree. Under deeply prolonged submergence, O. glaberrima genotypes were characterized by faster shoot elongation, anaerobic tillering, larger leaf area extension, higher photosynthetic rate, and maintenance of PSII maximum efficiency compared with Oiyza sativa genotypes without an escape mechanism. O. glaberrima employs a submergence escape strategy that effectively uses stored carbohydrates for shoot elongation and leaf extension in a severely photosynthesis-limited environment under complete submergence. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.fcr.2012.12.015

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

イネに対するプライミング処理により，低土壌含水率条件下においても発芽や出芽に要する時間が短縮し，シュートの伸長速度が大きくなることを明らかにした。この手法を技術確立することにより，直播栽培における苗立ちの安定性を確保できる可能性が示唆された。

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

An appropriate combination of rice cultivar and cropping system that maximizes water use efficiency (WUE) may improve yield of rainfed lowland rice. In the paddy field, a large amount of water is consumed by evaporation during the early growth period, and it can be reduced by canopy coverage especially in semi-arid regions. Therefore, we evaluated the role of canopy coverage in WUE of rice in the early growth period in semi-arid region. A pot experiment was conducted in Namibia to investigate the genotypic and species difference in WUE, and another pot and a field experiment were conducted to investigate the effects of planting density on WUE. Although no significant difference was observed among species, the mean WUE was in the decreasing order of Oryza sativa, and Oryza glaberrima followed by the interspecific progenies including NERICA. In contrast, there was a significant difference in WUE at the genotypic level. Highly tillering genotypes such as WAB1159-2-12-11-5-1 and WITA 2 showed a high WUE. Furthermore, WUE was significantly correlated with the number of tillers (R-2 = 0.453), and higher planting density resulted in a higher WUE. In contrast, stomatal conductance had no significant correlation with WUE (R-2 = 0.081). Thus, the physical conditions affected by number of tillers and planting density had greater impacts on WUE than physiological characteristics such as stomatal conductance. The suppression of surface water evaporation by coverage was significant, probably contributing to WUE improvement. To increase WUE in semi-arid regions, we recommend the increase of canopy coverage and higher planting density.

DOI： 10.1626/pps.16.12

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Scopus

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Sub-Saharan African countries are being strongly urged to enhance their rice production, because their rice consumption and importation rates have been rapidly increasing in recent years. Areas planted to rice in Africa are classified agro-ecologically into rainfed upland, rainfed lowland, and irrigated. Rainfed lowland includes extensive areas of unexploited land that has great potential for the promotion of rice growing. For the unexploited rainfed lowlands of Ghana, we have been studying the development of low-cost rice-farming systems that require no large-scale irrigation or land reclamation. For such systems, it is important to select suitable areas where water for rice farming can be obtained naturally; floodwaters offer promise for this purpose. Delineation and mapping of floodwater prone areas suitable for rice production is important for successful utilization of this land resource. Here, we propose a method of assessing flood probability from submergence frequency, as estimated from satellite imagery and geospatial data. ALOS/PALSAR images acquired in May, June, August, and September 2010 were used to classify land and water, and then a submerged-area map was produced. From the results, we were able to accurately detect non-submerged areas and submerged areas with water depths of at least 3 cm. The number of times classified into submerged area was defined as submergence frequency, and it was approximated by distance from reservoirs representing White Volta River, ponds, and swamps. In addition, flood extent derived from reservoirs was simulated using digital elevation model (DEM). Finally, a flood probability assessment map was produced by integration of the estimated submergence frequency and flood extent simulation. The results of a comparison of soil moisture data measured at 69 points in the field and the NDVIs computed by ALOS/AVNIR showed that areas with high potential for flooding retained high levels of soil moisture and were more likely to show less deterioration of vegetation in the dry season. The validation of these results confirmed the adequacy of the flood probability assessment method. © 2012 Springer Science+Business Media B.V.

DOI： 10.1007/s10668-012-9363-7

Scopus

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Rice plants cope with flash floods using either an 'escape strategy' involving rapid shoot elongation or a 'quiescence strategy' involving survival underwater with minimal activity. To clarify the differences in the response of leaf photosynthesis properties to conditions during and after submergence, two rice cultivars were compared: a non-shoot-elongating cultivar IR 67520-B-14-1-3-2-2 (IR67520) and a shoot-elongating cultivar IR72442-6B-3-2-1-1 (IR72442). Twenty-three-day-old seedlings were submerged in 80-cm-deep water for 14days. During submergence, the chlorophyll contents of the upper fully expanded leaf (5th leaf) and newly developed leaf later (6th leaf) and the maximal quantum yield of photosystem II (F /F ) of the fifth leaf decreased earlier in IR72442 than in IR67520. In the submerged sixth leaf, F /F was higher in IR72442 than in IR67520 at early measurement. Although F /F of the sixth leaf in submerged IR67520 increased substantially from 2days post-submergence, IR72442 decreased because of leaf chlorosis. Therefore, a non-shoot-elongating cultivar coped with submergence by inhibiting photodamage and maintaining high chlorophyll content in the leaves. The shoot-elongating cultivar was able to maintain the photosynthetic capacity of the newly developed leaf during submergence by prompt reduction of chlorophyll and chlorophyll fluorescence in the leaf that developed before submergence. © 2011 Blackwell Verlag GmbH. v m v m v m

DOI： 10.1111/j.1439-037X.2011.00494.x

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Scopus

Authorship：Corresponding author   Language：Japanese   Publisher：日本作物学会  

DOI： 10.1626/jcs.81.221

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：Japanese Society for Tropical Agriculture  

DOI： 10.11248/nettai.5.152

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：Japanese Society for Tropical Agriculture  

DOI： 10.11248/nettai.5.167

J-GLOBAL

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

Rice is one of the few submergence-resistant crops, but cannot grow under extended periods of complete submergence. The frequency of heavy rains and flooding is expected to increase due to global warming. Therefore, flood-control is extremely important in flood-prone rice cultivation areas. In rice plants, shoot elongation is generally accelerated by submergence to escape the submerged condition by photosynthesis under aerobic conditions on the water surface. When completely submerged by an abrupt rise in the water level at the seedling stage for a period of less than two weeks, the ethylene concentration is increased, foliage growth promoted, chlorophyll function in leaves fails, and energy consumption is increased by the rapid elongation, resulting in depletion of carbohydrates. The gene related to the escape from submergence through such internodal elongation is SNORKEL1, 2 (SKl, 2 ). However, some varieties of rice tolerate complete submergence by inhibiting the elongation of submerged stems and leaves, thus suppressing the consumption of carbohydrates instead. In such submergence-tolerant rice plants, elongation of stems and leaves is inhibited by suppression of the increase of ethylene concentration in the plant, which also decreases the sensitivity to gibberellins. Thus, the plant maintains a balance between carbohydrate supply and demand. The gene related to such submergence tolerance is SUBMERGENCE1 (Sub1). Physiological knowledge of these mechanisms of submergence tolerance will contribute to development of submergence-tolerant varieties of rice. © 2012, CROP SCIENCE SOCIETY OF JAPAN. All rights reserved.

DOI： 10.1626/jcs.81.1

Scopus

CiNii Books

J-GLOBAL

Other Link： https://agriknowledge.affrc.go.jp/RN/2010830041

Authorship：Corresponding author   Language：Japanese   Publisher：国際農林業協働協会  

CiNii Books

J-GLOBAL

Authorship：Corresponding author   Publishing type：Research paper (scientific journal)  

The main strategies enabling rice plants to cope with flash flooding stress require growth regulation during submergence and subsequent rapid growth recovery after de-submergence. The objective of this study was to characterize the response of 56 diverse contrasting rice genotypes to submergence and their recovery following de-submergence. Among these genotypes, nine lines had been developed for anaerobic germination and submergence tolerance (AG + Sub1) by IRRI. Fourteen-day-old plants were submerged completely in water for 7 days. Subsequently, the plants were kept under normal rice-cultivation conditions as the control for a further period of 5 days. The tested genotypes were generally classified into three clusters based on shoot elongation rate of submerged to non-submerged treatments (ratio) during submergence period and chlorophyll contents during recovery period using Ward's method. The genotypes in clusters I include most of AG + Sub1 lines and tolerant genotype FR13A adapted to submergence stress, which get the benefits of quiescence mechanism during submergence coupled with maintenance of higher chlorophyll content during recovery period. In contrast, the cluster III spanned most of intolerant genotypes such as IR42 by enhancing shoot elongation through escape mechanism in response to submergence. This mechanism negatively affected the plant growth recovery due to a great reduction of chlorophyll contents during the recovery period. The genotypes placed in cluster II followed the similar trend as cluster I during the submergence and recovery periods in addition of increases in shoot fresh weight during submergence period. This finding suggests that other mechanisms along with quiescence might be associated with submergence stress in the genotypes placed in cluster II. In conclusion, the contrasting rice genotypes expressed differential growth responses in genotypes with lower shoot elongation ratio using different quiescence strategies during submergence period.

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Lead author,　Corresponding author  

DOI： 10.3759/tropics.20.55

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publisher：The Association for Regional Agricultural and Forestry Economics  

In Africa, the consumption of rice has been increasing rapidly in recent years, but the self-sufficiency ratio remains low. This paper attempted to investigate the profitability of rice and its limiting factor to expansion in the northern part of Ghana.<br>The results show that farmers were highly motivated to participate in rice production, as rice can be converted into money as a cash crop. However, several problems, including the shortage of fundsfor materials, charge for use of tractors, unreliable tractor operation, labor shortage, and conflicts with other plantations, were hindering rice development in the lowlands. A cost analysis showed that the cost of using tractors accounted for almost 60% of the total cash expenditure in rice production. Therefore, the invention of low-input cultivation technology in accordance with the local environment is required for the promotion of rice cultivation.

DOI： 10.7310/arfe.47.308

CiNii Books

J-GLOBAL

Other Link： https://agriknowledge.affrc.go.jp/RN/2010815233

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：GORGAN UNIV AGRICULTURAL SCIENCES & NATURAL RESOURCES  

Parameters that show a significant genotypic variation at early growth stages and are associated with salt tolerance at later stages may be used as rapid and economic screening criteria in breeding programs. The objective of this study was to test growth parameters at early growth stages for evaluating the salt tolerance of wheat genotypes. Ten wheat genotypes that differ from their salt tolerance were grown in soil and exposed to four salinity concentrations (0, 40, 80 and 160 mM NaCl). Germination percentage was recorded daily up to 8 days. Seedling growth parameters (i.e. shoot height, dry weight of shoots and roots and root/shoot ratio) were determined at day 14 after sowing. The results showed that salinity did not affect final germination percentage, while seeds subjected to 80 and 160 mM NaCl retarded germination by 1 and 2 days, respectively, as compared with 0 mM NaCl treatment. Salinity affected shoot growth more severely than root growth of seedlings. Importantly, height and dry weight of shoot ranked genotypes in the same order as their salt-tolerance rankings in terms of grain yield, whereas root dry weight did not. Therefore, we conclude that the measurements of shoot growth may be effective criteria for screening wheat genotypes for salt tolerance at early growth stages.

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Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Authorship：Lead author,　Corresponding author   Language：Japanese  

DOI： 10.3719/weed.56.24

J-GLOBAL

Authorship：Lead author,　Corresponding author   Language：Japanese  

J-GLOBAL

Language：Japanese  

J-GLOBAL

Language：Japanese   Publisher：缶詰技術研究会  

CiNii Books

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Slow seed germination and delayed seedling establishment will become a major problem for rice production in flood-prone lowland areas as sowing method shifts from transplanting to direct seeding. To address this problem, the relationships between genotypic differences in the pattern of water uptake over different times of seed imbibition and adaption to anaerobic conditions were studied. The pattern of water uptake and germination time under aerobic and anaerobic conditions was evaluated for fifty-eight contrasting rice genotypes. Among them, nine lines had been developed for anaerobic germination (AG) and submergence tolerance (Subl) by the International Rice Research Institute. In addition FR13A, with a designated Subl gene and IR42 without the Subl gene were used as model genotypes. Results showed that cluster analysis separated the genotypes into three groups based on the water content in seeds at different times of seed imbibition. Most AG+Subl lines were placed in cluster 3 which was characterized by rapid water uptake during the first 48 h of seed imbibition and rapid germination under aerobic and anaerobic conditions. Cluster 1 and 2 included genotypes with slower water uptake during the first 48 h and between 96 and 120 h of seed imbibition compared with cluster 3 under anaerobic condition. Therefore, these genotypes germinated more slowly than AG+Subl lines. The significant variation between two model genotypes in germination time was not significant under anaerobic condition. The present results verified that the regulation of water uptake during rice seed imbibition play an important rule in germination ability of rice seeds under anaerobic conditions. © 2011 Academic Journals Inc.

DOI： 10.3923/rjss.2011.82.93

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Salinity tolerance has been extensively studied in Oryxa sativa, but little is known about the salt tolerance levels in Oryxa glaberrima and the interspecific progenies including New Rice for Africa (NERICA). In this study, the salinity tolerance of the three cultivated rice species, O. glaberrima (54 genotypes), the interspecific progenies (21) including NERICA (7) and O. sativa (41) mainly grown in West Africa were examined comparatively. At 10 days after sowing (DAS) 80 mM NaCl was added to the culture solution, and the plants were grown for 10 more d. The ratio of shoot biomass in the 80 mM NaCl solution to that in the control was significantly higher in the interspecific progenies than in the other two species, and the relative root biomass was significantly lower in O. glaberrima than in the others. The vegetative growth of six genotypes including the salt tolerant Pokkali, and NERICA4 and its parents were evaluated further in pot experiments irrigated with 80 mM NaCl solution from 22 to 52 d after sowing. At 30 d of the salt stress, CG14 and Mala noir IV (O. glaberrima) were killed by salt, while WAB56-104 and NERICA4 survived; Pokkali maintained the highest relative shoot biomass growth at all sampling times of 10 d intervals. These results indicate that O. glaberrima is relatively weaker to NaCl salinity, while the interspecific progenies are fairly tolerant during the seedling stage, and that the relatively high salt stress tolerance of NERICA4 is derived from the O. sativa parent, WAB56-104.

DOI： 10.1626/pps.13.3

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Authorship：Lead author,　Corresponding author   Language：Japanese  

J-GLOBAL

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：農林水産先端技術産業振興センター  

CiNii Books

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TUBITAK SCIENTIFIC & TECHNICAL RESEARCH COUNCIL TURKEY  

The use of chemical inducers for the development of host resistance is an alternative approach to plant disease management and is assumed to be much more environmentally sound than traditional pesticides. Five chemical inducers, salicylic acid, oxalic acid, ascorbic acid, dipotassium hydrogen phosphate (KH2PO4), and calcium chloride (CaCl2), all at concentrations of 10 mM, and an untreated control treatment were applied by seed soaking to compare their effectiveness in inducing resistance against chocolate spot disease (Botrytis fabae Sard.) in faba bean under greenhouse and field conditions, and to investigate whether use of these chemicals in this way is associated with a reduction in plant growth and yield under field conditions. A field experiment was conducted over 2 years (2007 and 2008) using a randomized complete block design with 4 replications. Results indicated that, under greenhouse and field conditions, KH2PO4 and CaCl2 treatments were either moderately or less effective in reducing disease severity of chocolate spot. However, both inducers significantly increased the growth and yield of faba beans under field conditions compared with the untreated control treatment. The greatest reduction in disease severity of chocolate spot under greenhouse and field conditions was observed in treatments of ascorbic acid and oxalic acid. The decrease in disease severity ranged from 70.6% to 79.9% for oxalic acid and from 68.1% to 80.2% for ascorbic acid, as compared with the untreated control under greenhouse conditions. Under field conditions, the decreases in disease severity with ascorbic acid and oxalic acid treatments relative to the untreated control were 79.4% and 71.3% on day 30, 62.4% and 41.8% on day 45, and 60.1% and 41.1% on day 60, respectively. The treatments of salicylic acid and oxalic acid produced the lowest values for growth and yield parameters. These results led to the conclusion that, for field application of chemical inducers to develop host resistance, it is important to study their effects on growth and yield in addition to their ability to control diseases.

DOI： 10.3906/tar-0908-340

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Reducing damage to rice seedlings caused by flash flooding will improve the productivity of rainfed lowland rice in West Africa. Accordingly, the morphological and physiological responses of different forms of rice to complete submergence were examined in field and pot experiments to identify primary causes of damage.To characterize the physiological responses, seedlings from a wide genetic base including Oryza sativa, O. glaberrima and interspecific hybrids were compared using principle component analysis.Important factors linked to flash-flood tolerance included minimal shoot elongation underwater, increase in dry matter weight during submergence and post-submergence resistance to lodging. In particular, fast shoot elongation during submergence negatively affected plant growth after de-submergence. Also shoot-elongating cultivars showed a strong negative correlation between dry matter weight of the leaves that developed before submergence and leaves developing during submergence.Enhancement of shoot elongation during submergence in water that is too deep to permit re-emergence by small seedlings represents a futile escape strategy that takes place at the expense of existing dry matter in circumstances where underwater photosynthetic carbon fixation is negligible. Consequently, it compromises survival or recovery growth once flood water levels recede and plants are re-exposed to the aerial environment. Tolerance is greater in cultivars where acceleration of elongation caused by submergence is minimal.

DOI： 10.1093/aob/mcn171

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PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

is widely grown in flood-prone areas of African river basins and is subject to prolonged periods of annual submergence. The effects of submergence on shoot elongation, shoot biomass, leaf area and CO2 uptake were studied and compared with those of O. sativa.A wide selection of lines of O. sativa and O. glaberrima, including some classified as submergence tolerant, were compared in field and pot experiments. Plants were submerged completely for 31 d in a field experiment, and partially or completely for 37 d in a pot experiment in a growth chamber.Leaf elongation and growth in shoot biomass during complete submergence in the field were significantly greater in O. glaberrima than in O. sativa. So-called submergence-tolerant cultivars of O. sativa were unable to survive prolonged complete submergence for 31-37 d. This indicates that the mechanism of suppressed leaf elongation that confers increased survival of short-term submergence is inadequate for surviving long periods underwater. The O. sativa deepwater cultivar 'Nylon' and the 'Yele1A' cultivar of O. glaberrima succeeded in emerging above the floodwater. This resulted in greatly increased shoot length, shoot biomass and leaf area, in association with an increased net assimilation rate compared with the lowland-adapted O. sativa 'Banjoulou'.The superior tolerance of deepwater O. sativa and O. glaberrima genotypes to prolonged complete submergence appears to be due to their greater photosynthetic capacity developed by leaves newly emerged above the floodwater. Vigorous upward leaf elongation during prolonged submergence is therefore critical for ensuring shoot emergence from water, leaf area extension above the water surface and a subsequent strong increase in shoot biomass.

DOI： 10.1093/aob/mcn201

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PubMed

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.227.0.406.0

CiNii Books

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN INT RESEARCH CENTER AGRICULTURAL SCIENCES  

In inundation areas in rainfed lowland and inland valleys of Guinea well as other regions in Africa, submergence for a Few days to a few weeks with a water depth less than 50 cm occurs in rice cultivation during the rainy season. Young rice seedlings after transplanting are particularly vulnerable to submergence stress. Oryza glaberrima Steud. is well adapted to growth in inundation areas with deepwater conditions in West Africa; however, it is not evident whether it resists short-term submergence stress after transplanting. The purpose of the study Was to understand the physiological responses of rice plants after transplanting to short-term submergence stress Under rainfed conditions for O. glaberrima by comparison with several genotypes of Oryza sativa L. from Guinea. Eight genotypes of O. glabeirima and seven genotypes of O. sativa including two shoot elongation genotypes, one submergence tolerant genotype as a control cultivars, and four genotypes of common cultivars in West Africa were used. Thirty day-old seedlings were submerged completely for 10 days with medium deepwater conditions at 45 cm water depth at 13 days after transplanting ill a lowland field. O. glaberrima showed higher shoot elongation ability during submergence than my genotype of O. sativa that we tested. However. O. glaberrima lodged easily after desubmergence due to longer and rapid shoot elongation during submergence, and thus triggered a decrease ill its Survival rate. The submergence tolerant genotype of O. sativa maintained the dry matter weight ofthe leaf blade during Submergence through the inhibition of shoot elongation. We suggest that O. glaberrima is susceptible to short-term Submergence while it may adapt to prolonged flooding because of improved restoration of aerial photosynthesis and survival rat, through shoot elongation ability.

DOI： 10.6090/jarq.42.157

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Rice plants are damaged by flash floods with a rapid increase in water level caused by a heavy rain. However, rice plants cope with the flash floods either by an "escape strategy" involving rapid shoot elongation or by a "quiescence strategy" involving surviving under water with minimal activity. As we found in previous experiments, Saligbeli cultivar adapted well to flash floods through rapid shoot elongation. To understand the vigorous growth process during submergence, we studied the relationship between shoot elongation and changes in dry matter weight (DMW) during submergence. O. glaberrima Steud. cv Saligbeli and O. saliva L. cv. Ballawe and IR 49830-7-1-2-2 were used. Saligbeli and Ballawe exhibit shoot elongation, and IR 49830-7-1-2-2 exhibits flash-flood tolerance due to the presence of the Sub-1 gene. Twelve-day-old seedlings were submerged for 7 days and the plant length and DMW were measured. The plant length ratio of submerged to control plants in Saligbeli was higher than that of other cultivars during 2-6 days of submergence but IR 49830-7-1-2-2 shoot elongation was inhibited by submergence. In all three cultivars, the elongation of the developing leaf sheath conferred shoot elongation during submergence. The plant length of all submerged plants showed a strong positive correlation with DMW of the leaves developed during submergence. Submerged Saligbeli and Ballawe showed strong negative correlations between DMW of the leaves developed before and during submergence (r = -0.786 for Saligbeli and -0.772 for Ballawe, P<0.05), suggesting that the enhancement of shoot elongation during submergence is accomplished by using dry matter of the leaves developed before submergence. However, the correlation was not observed in the submerged IR 49830-7-1-2-2. Further details from studies using isotopes are also needed to understand the plant growth during submergence.

DOI： 10.1626/pps.11.316

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

In the costal area and inland valleys of Guinea, flash floods occur frequently following heavy rain during the rainy season. Young rice seedlings are particularly vulnerable to submergence stress due to insufficient height and carbohydrate reserves. In an attempt to characterize the physiological responses of young seedlings to flash flood, a wide genetic base including O. sativa, O. glaberrima, and interspecific hybridization progenies (IHP) was used.Twelve day-old seedlings were submerged for 7 days, and plant height, dry matter accumulation (I)MA), and lodging were measured. Upland rice (O. sativa) showed greater shoot elongation, larger reduction in DMA during submergence, and higher lodging, which lead to low flash flooding resistance (FFR). The physiological traits of most O. glaberrima and upland rice (O. sativa) to flash flood were opposite to those of submergence tolerant cultivars, as evidenced from the results of a principal component analysis. The physiological response of Saligbeli was different to other O. glaberrima genotypes in terms of FFR. Saligbeli exhibited enhanced shoot elongation with the increase in DMA during submergence. These features seemed to be a unique way to cope with submergence. Some IHP adapted to lowland cultivation showed traits similar to Saligbeh. The vigorous growth of Saligbeli and IHP underwater should be further investigated for improving FFR in rice. (c) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.envexpbot.2007.12.001

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Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (other academic)  

Language：Japanese   Publisher：養賢堂  

CiNii Books

Authorship：Lead author,　Corresponding author   Language：Japanese  

J-GLOBAL

Language：English   Publisher：The Crop Science Society of Japan  

CiNii Books

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN INT RESEARCH CENTER AGRICULTURAL SCIENCES  

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Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

This paper examines the research-extension-farmer linkage system in Southwestern Nigeria due to the fact that many farmers have not been properly reached by agricultural extension services and the problem of poor food production has been attributed to the weak linkages existing between research, extension and farmers. Simple random sampling technique was used to select researchers, extension agents and farmers and their responses on involvement in linkage activities were elicited through a questionnaire. The result showed that there is a significant difference in the involvement of researchers, extension agents and farmers in linkage activities (F = 9.188, p < 0.05). The mean involvement score revealed that extension agents (68.00) are mostly involved in linkage activities followed by researchers (44.46) and then farmers (39.06). The paper concludes with the need for a closer collaboration among the three components.

Scopus

Authorship：Lead author,　Corresponding author   Language：English   Publisher：農業生物資源研究所  

CiNii Books

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL VERLAG GMBH  

Three levels of shade (0, 45 and 70 %) on rice was studied by changing the time of nitrogen top dressing application. The shade was given for the respective plots from heading up to harvesting and the top dressing was applied 20 days (standard) and 5 days (late) before heading. Significant yield reduction was not observed under the given conditions but ripening percentage and thousand-grain weight was significantly affected. Ripening rate was found as the key factor that determined the rice yield under low light intensities. The adverse effects of shade on the yield and yield components were not able to significantly minimize by the change of the timing of application of nitrogen top dressing. © 2005 Blackwell Verlag.

DOI： 10.1111/j.1439-037X.2004.00132.x

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WFL PUBL  

This paper presents an analysis of the strengths, weaknesses, opportunities, and threats to extension organizations in Japan, China, Thailand, Nigeria, Cote d'Ivoire and Ghana. This is based on the fact that there are new emerging roles of extension services, need for improved performance, as well as the need to re-position the organizations for future challenges. Some of the strengths are strong linkage among research, extension and farmers, complete organization from national to township level, extensive coverage of farming population, and high feasibility of plans while weaknesses include limited use of alternative extension methods, insufficient cooperation, and coordination with other agencies, high bureaucratic setting, and poor financial decentralization. On the other hand the opportunities that can be explored are potential for improved effectiveness and efficiency through transformations, emergence of private extension services providers and potential for effective programme implementation. The threats to these organizations include too rigid structure, limited use of alternative extension methods, multiplicity of extension advisors roles and inadequate budget. The paper recommends that the extension managers and policy makers should focus on the identified strengths, weakness, opportunities, and threats with a view of evolving an effective and sustainable extension system.

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Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WFL PUBL  

This paper presents the trend of agricultural extension systems used in the Nigerian agriculture. The pluralistic nature of these systems is partly due to the donor induced and the peculiar socio-cultural milieu of the operators of these systems. The potentials of a new era of support for national extension programs, a number of serious issues within the domain of extension practice program remain to be addressed. While often masked under the new titles and phrases of the current development discourse, the challenges faced today reflect many of the perennial problems that have plagued development efforts. These include, the challenges of: becoming truly responsive to local conditions and concerns; facilitating constructive inter-organizational collaboration; fostering greater local self-reliance through individual capacity-building and local institutional development; addressing financial insecurity and low educational levels of extension staff; and the specific interests of engaging indigenous knowledge, farmer inventiveness and farmer-to-farmer communication. The extension systems considered are: Ministry Based Agricultural Extension, Farm Settlement Scheme, National Accelerated Food Production Programme (NAFPP), Operation Feed The Nation (OFN), River Basin Development Authority (RBDA), Green Revolution (GR), The Pilot Agricultural Development Project (PADP), Agricultural Development Projects (ADPS), Unified Agricultural Extension System (UAES), Women - In - Agriculture (WIA), National Agricultural Land Development Authority (NALDA), Nationally Coordinated Research Programme (NCRP), Farming System Research And Extension (FSRE), Training and Visit System(T&V), Research - Extension - Farmer - Input Linkage System (REFILS), Non -Governmental Organizations (NGO), Information and Communication Support For Agricultural Growth In Nigeria (ICS- Nigeria), Farmer Field Schools (FFS). The paper concludes with pragmatic steps of evolving a sustainable extension system.

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Language：Japanese   Publisher：The Clay Science Society of Japan  

The low soil fertility in semi-arid land requires effective soil improvement measures. To elucidate a possible relationship between dominant minerals and organic materials that improves soil fertility in semi-arid land, several experiments is carried out using kaolinite and urea. The reaction rate of urea-kaolinite complex is determined using XPS and XRD. It is confirmed that the intercalated urea is easily released from the structure of urea-kaolinite complex after dissolution experiments. Soil-forming minerals and native organic polymer compounds which contain nitrogen distributes in semi-arid soil. We will carry out a study at semi-arid land whether complexes will be able to support more efficient agricultural productivity and to determine the applicability of the results obtained to low-fertility areas.

DOI： 10.11362/jcssjnendokagaku1961.43.116

CiNii Books

J-GLOBAL

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese  

J-GLOBAL

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Doctoral thesis  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Crop Science Society of Japan  

Ten cultivars of O. saliva (6 japonica, 2 indica, and 2 japonica X indica) and five cultivars of O. glaberrima were grown in pots. Half of each cultivar was cut at 10cm above the ground at maturity, and the other half remained uncut. Both were grown under two different day-length conditions with a suitable temperature. The growth state at maturity, the changes in the number of living tillers after maturity, and the survival rate after maturity were examined. The starch content in the stem (stem+leaf sheath) of 0. saliva at maturity tended to be higher than that of 0. glaberrima. The nodal root number and the total leaf length of the tiller bud from the node of a stem section at maturity were greater in 0. saliva than in 0. glaberrima. New tillers appeared in both 0. saliva and O. glaberrima after maturity. The number of living tillers after maturity was always greater in 0. saliva than in 0. glaberrima, though the relation was reversed for some period in the long day uncut plot because of the appearance of new tillers from higher nodes. The long day and the uncut conditions enhanced the survival of tillers. In 0. glaberrima, the survival rate of all cultivars at 250 days after maturity was nil. In 0. saliva, japonica cultivars were higher than indica cultivars, including japonica X indica cultivars in the survival rate at 250 days after maturity. All plants of some indica cultivars had died before 250 days after maturity. The long-day condition favored the survival rate. The continued appearance of new tillers in both 0. saliva and O. glaberrima after maturity suggested that both 0. saliva and O. glaberrima had potential perennial ability. It was inferred that the perennial ability of O. glaberrima was very small compared with that of 0. saliva. It was also inferred that varietal differences in the survival rate existed in O. saliva.

DOI： 10.1626/jcs.68.257

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CiNii Books

Other Link： https://agriknowledge.affrc.go.jp/RN/2010591893

Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Crop Science Society of Japan  

The growth and survival after maturity of 26 cultivars of japonica, 37 cultivars of indica, and 41 cultivars of O. glaberrima were examined to clarify the annuality and perenniality of two cultivated species. These cultivars were grown in pots and under light of natural day length with a suitable temperature regime. They were left uncut till 225 days after maturity, approximately one year after seeding. The number of new tillers appearing from maturity to 225 days after maturity was greatest in japonica and lowest in O. glabmima. The number of living tillers increased with time for a short while after maturity and then decreased, although in japonica, it increased again 120 days after maturity and thereafter. The survival duration of cultivars after maturity was clearly longer for O. sativa than for O. glaberrima. In japonica, all of the Japanese cultivars and all of the foreign cultivars except two survived longer than 225 days after maturity. In indica, most cultivars survived longer than 225 days after maturity, but several cultivars died in the early stage after maturity. In O. glaberrima, all the cultivars except one died before 225 days after maturity. From these results, it was concluded that O. sativa included both annual and perennial cultivars, whereas O. glaberrima was monocarpic annual. It was inferred that O. sativa inherited its genetical characteristics from O. rufipogon, which was thought to be the ancestor of O. sativa and included both annuals and perennials, and O. glaberrima inherited its characteristics from O. barthii, which was annual.

DOI： 10.1626/jcs.68.524

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Other Link： https://agriknowledge.affrc.go.jp/RN/2010601451

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：養賢堂  

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J-GLOBAL

Language：Japanese Book type：Scholarly book

Language：Japanese

Language：English Book type：Scholarly book

Language：Japanese Book type：Report

Language：English Book type：Scholarly book

Language：English Book type：Scholarly book

Language：Japanese Book type：Report

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Language：Japanese Book type：Scholarly book

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Language：Japanese Book type：Scholarly book

Language：Japanese Book type：Scholarly book

Language：Japanese Book type：Scholarly book

Language：Japanese Book type：Report

Language：Japanese Book type：Report

Language：Japanese Book type：Report

Language：Japanese Book type：Report

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Language：Japanese Book type：Report

Language：Japanese Book type：Report

Language：Japanese Book type：Report

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J-GLOBAL

J-GLOBAL

J-GLOBAL

J-GLOBAL

Language：English  

J-GLOBAL

Language：English  

J-GLOBAL

© 2019, ALÖKI Kft., Budapest, Hungary. Phosphorus (P) is an essential nutrient element required for plant growth and development. Low phosphorus availability in soil is one of the major constrains for crop production. Phosphate solubilizing fungi enhance available phosphorous released from soils and contribute to fulfill the plants phosphorous requirement. This study aimed to isolate and identify potential phosphate solubilizing fungi from subtropical soils for environment friendly biofertilizer development. Sixteen fungal strains were isolated and identified as Aspergillus spp., Penicillium spp. and Talaromyces spp. from subtropical dark red soil, red soil and grey soil based on phosphate solubilization index, morphological studies and the sequences of β-tubulin and/or Calmodulin. Subsequently, fungal isolates having excellent phosphate solubilization efficiency were selected by their potential in broth containing insoluble Ca3 (PO4)2, AlPO4 and FePO4. Interestingly, Aspergillus niger isolates (strain SI-10URAgr, SI-11URAgr and SI-12URAgr) have marked phosphate solubilization ability regardless of the substrates followed by Panicillium oxalicum and Talaromyces pinophilus. In addition, there was inverse proportion between the pH and phosphate solubilizing capacities. These excellent properties of strains suggested that they have a great potential for agricultural utilization as environmentally sound biofertilizer. In this study, phosphate solubilization by filamentous fungi is reported for the first-time in subtropical Okinawa.

DOI： 10.15666/aeer/1704_91459157

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J-GLOBAL

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_71

J-GLOBAL

J-GLOBAL

J-GLOBAL

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_123

J-GLOBAL

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.247.0_29

J-GLOBAL

J-GLOBAL

J-GLOBAL

J-GLOBAL

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.245.0_96

J-GLOBAL

J-GLOBAL

J-GLOBAL

J-GLOBAL

J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.1626/jcs.83.273

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.237.0_162

J-GLOBAL

Language：Japanese   Publisher：一般社団法人日本粘土学会  

DOI： 10.11362/cssj2.58.0_112

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J-GLOBAL

Publisher：The Association of Japanese Geographers  

DOI： 10.14866/ajg.2013s.0_3

J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.235.0_2

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J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.235.0_132

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J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.236.0_272

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J-GLOBAL

Language：Japanese   Publisher：日本作物学会  

DOI： 10.1626/jcs.82.295

J-GLOBAL

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Language：Japanese  

J-GLOBAL

Language：Japanese   Publisher：Crop Science Society of Japan kanto Branch  

DOI： 10.20768/jcskanto.27.0_34

CiNii Books

Language：Japanese   Publisher：The Clay Science Society of Japan  

DOI： 10.11248/nettai.5.160

DOI： 10.11362/cssj2.55.0_160

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J-GLOBAL

Language：Japanese  

J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.231.0.364.0

CiNii Books

Language：Japanese  

J-GLOBAL

Language：Japanese  

J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.230.0.6.0

CiNii Books

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.230.0.288.0

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J-GLOBAL

Language：Japanese   Publisher：Crop Science Society of Japan kanto Branch  

DOI： 10.20768/jcskanto.24.0_40

CiNii Books

Language：English   Publisher：National Institute of Agrobiological Sciences  

DOI： 10.24514/00004602

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.224.0.56.0

J-GLOBAL

Language：Japanese   Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.224.0.172.0

J-GLOBAL

Language：Japanese   Publisher：日本作物学会東海支部  

CiNii Books

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.221.0.206.0

Language：Japanese  

DOI： 10.14829/jcsproc.221.0.206.0

J-GLOBAL

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.221.0.210.0

J-GLOBAL

Publisher：CROP SCIENCE SOCIETY OF JAPAN  

DOI： 10.14829/jcsproc.221.0.204.0

J-GLOBAL

Language：Japanese   Publisher：The Crop Science Society of Japan  

CiNii Books

Language：Japanese   Publisher：The Crop Science Society of Japan  

CiNii Books

J-GLOBAL

J-GLOBAL

Language：Japanese   Publisher：Crop Science Society of Japan  

Ten cultivars of O. sativa (6 japonica, 2 indica, and 2 japonica X indica) and five cultivars of O. glaberrima were grown in pots. Half of each cultivar was cut at 10 cm above the ground at maturity, and the other half remained uncut. Both were grown under two different day-length conditions with a suitable temperature. The growth state at maturity, the changes in the number of living tillers after maturity, and the survival rate after maturity were examined. The starch content in the stem (stem+leaf sheath) of O. sativa at maturity tended to be higher than that of O. glaberrima. The nodal root number and the total leaf length of the tiller bud from the node of a stem section at maturity were greater in O. sativa than in O. glaberrima. New tillers appeared in both O. sativa and O. glaberrima after maturity. The number of living tillers after maturity was always greater in O. sativa than in O. glaberrima, though the relation was reversed for some period in the long day uncut plot because of the appearance of new tillers from higher nodes. The long day and the uncut conditions enhanced the survival of tillers. In O. glaberrima, the survival rate of all cultivars at 250 days after maturity was nil. In O. sativa, japonica cultivars were higher than indica cultivars, including japonica X indica cultivars in the survival rate at 250 days after maturity. All plants of some indica cultivars had died before 250 days after maturity. The long-day condition favored the survival rate. The continued appearance of new tillers in both O. sativa and O. glaberrima after maturity suggested that both O. sativa and O. glaberrima had potential perennial ability. It was inferred that the perennial ability of O. glaberrima was very small compared with that of O. sativa. It was also inferred that varietal differences in the survival rate existed in O. sativa.

DOI： 10.1626/jcs.68.257

Scopus

J-GLOBAL

Language：Japanese   Publisher：The Crop Science Society of Japan  

CiNii Books

J-GLOBAL

Language：English   Publisher：The Crop Science Society of Japan  

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