Abstract

Evolution of mating systems has become one of the most important research areas in evolutionary biology. Cyrtomium falcatum is a homosporous fern species native to eastern Asia. Two subspecies belonging to a sexual diploid race of C. falcatum are recognized: subsp. littorale and subsp. australe. Subspecies littorale shows intermediate selfing rates, while subsp. australe is an obligate outcrosser. We aimed to evaluate the process of mating system evolution and divergence for the two subspecies using restriction site associated DNA sequencing (RAD-seq). The results showed that subsp. littorale had lower genetic diversity and stronger genetic drift than subsp. australe. Fluctuations in the effective population size over time were evaluated by extended Bayesian skyline plot and Stairway plot analyses, both of which revealed a severe population bottleneck about 20,000 years ago in subsp. littorale. This bottleneck and the subsequent range expansion after the LGM appear to have played an important role in the divergence of the two subspecies and the evolution of selfing in subsp. littorale. These results shed new light on the relationship between mating system evolution and past demographic change in fern species.

Details

Title
Mating system evolution and genetic structure of diploid sexual populations of Cyrtomium falcatum in Japan
Author
Imai Ryosuke 1 ; Tsuda Yoshiaki 1 ; Ebihara Atsushi 2 ; Matsumoto Sadamu 2 ; Tezuka Ayumi 3 ; Nagano, Atsushi J 3 ; Ootsuki Ryo 4 ; Watano Yasuyuki 5 

 Sugadaira Research Station, Mountain Science Center, University of Tsukuba, Ueda, Japan (GRID:grid.20515.33) (ISNI:0000 0001 2369 4728) 
 National Museum of Nature and Science, Department of Botany, Tsukuba, Japan (GRID:grid.410801.c) 
 Ryukoku University, Faculty of Agriculture, Otsu, Japan (GRID:grid.440926.d) (ISNI:0000 0001 0744 5780) 
 Komazawa University, Department of Natural Sciences, Faculty of Arts and Sciences, Tokyo, Japan (GRID:grid.440902.b) (ISNI:0000 0001 2185 2921) 
 Chiba University, Department of Biology, Graduate School of Science, Chiba, Japan (GRID:grid.136304.3) (ISNI:0000 0004 0370 1101) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2574932782
Copyright
© The Author(s) 2021. corrected publication 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.