記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Annals of botany  

BACKGROUND AND AIMS: Plant propagules often possess specialized morphologies that facilitate dispersal across specific landscapes. In the fruit dimorphism of a coastal shrub, Scaevola taccada, individual plants produce either cork-morph or pulp-morph fruits. The former is buoyant and common on sandy beaches, whereas the latter does not float, is bird-dispersed, and is common on elevated sites such as slopes on sea cliffs and behind rocky shores. We hypothesized that beach populations bridge the heterogeneous landscapes by serving as a source of both fruit types, while dispersal is biased for the pulp morph on elevated sites within the islands and for the cork morph between beaches of different islands. Based on this hypothesis, we predicted that populations in elevated sites would diverge genetically over time due to isolation by distance, whereas beach populations would maintain high genetic similarity via current gene flow. METHODS: The genetic structure and gene flow in S. taccada were evaluated by investigating genome-wide single nucleotide polymorphisms in plants from 17 sampling sites on six islands (belonging to the Ryukyu, Daito and Ogasawara Islands) in Japan. KEY RESULTS: Geographical isolation was detected among the three distant island groups. Analyses within the Ryukyu Islands suggested that sandy beach populations were characterized by genetic admixture, whereas populations in elevated sites were relatively isolated between the islands. Pairwise FST values between islands were lowest between sandy beaches, intermediate between sandy beaches and elevated sites, and highest between elevated sites. CONCLUSIONS: Dispersal across the ocean by cork morphs is sufficiently frequent to prevent genetic divergence between beaches of different islands. Stronger genetic isolation of elevated sites between islands suggests that bird dispersal by pulp morphs is restricted mainly within islands. These contrasting patterns of gene flow realized by fruit dimorphism provide evidence that fruit characteristics can strongly mediate genetic structure.

DOI： 10.1093/aob/mcac138

Scopus

PubMed

記述言語：日本語   出版者・発行元：樹木医学会  

DOI： 10.18938/treeforesthealth.26.2_79

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：日本語   出版者・発行元：樹木医学会  

DOI： 10.18938/treeforesthealth.25.2_67

担当区分：最終著者,　責任著者  

担当区分：筆頭著者  

開催年月日： 2021年10月 - 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2021年10月 - 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年3月

記述言語：日本語   会議種別：ポスター発表  

開催年月日： 2019年10月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2019年10月

記述言語：日本語   会議種別：口頭発表（一般）