Tetraploids expanded beyond the mountain niche of their diploid ancestors in the mixed-ploidy grass Festuca amethystina L.

Marcin Kiedrzyński,Vladimir Stupar,Iwona Jedrzejczyk,Jan Roleček,Adrian Indreica,Katarzyna M Zielińska,Agnieszka Rewicz,Petr Šmarda,Iryna Bednarska,Monika Rewers,Edyta Kiedrzyńska,Przemysław P Tomczyk

doi:10.1038/s41598-021-97767-6

Abstract

One promising area in understanding the responses of plants to ongoing global climate change is the adaptative effect of polyploidy. This work examines whether there is a coupling between the distribution of cytotypes and their biogeographical niche, and how different niches will affect their potential range. The study uses a range of techniques including flow cytometry, gradient and niche analysis, as well as distribution modelling. In addition, climatic, edaphic and habitat data was used to analyse environmental patterns and potential ranges of cytotypes in the first wide-range study of Festuca amethystina—a mixed-ploidy mountain grass. The populations were found to be ploidy homogeneous and demonstrate a parapatric pattern of cytotype distribution. Potential contact zones have been identified. The tetraploids have a geographically broader distribution than diploids; they also tend to occur at lower altitudes and grow in more diverse climates, geological units and habitats. Moreover, tetraploids have a more extensive potential range, being six-fold larger than diploids. Montane pine forests were found to be a focal environment suitable for both cytotypes, which has a central place in the environmental space of the whole species. Our findings present polyploidy as a visible driver of geographical, ecological and adaptive variation within the species.

Highlights

One promising area in understanding the responses of plants to ongoing global climate change is the adaptative effect of polyploidy
One especially promising area of research is the adaptative effect of polyploidy, i.e. the multiplication of an entire chromosome set, which is an important catalyst of ecological diversification in p lants[4,5]
Our data indicate that the cytotype distribution of pure-ploidy populations of F. amethystina follows a parapatric pattern

Summary

Introduction

One promising area in understanding the responses of plants to ongoing global climate change is the adaptative effect of polyploidy. Despite progress in understanding the genetic and genomic effects of polyploidy, their ecological consequences remain poorly understood[7,8] Such studies have considerable social and environmental significance, when considering how many polyploid species are ecosystem dominant and economically important[5]. The most appropriate models for studies of the adaptative effects of polyploidy are those based on mixed-ploidy species[11] In such complexes, the knowledge of the distribution of cytotypes within species range and its ecological niches may clarify the processes that influence polyploid establishment and adaptation. If polyploids have broader ecological amplitudes and lower inbreeding depression, and are more selfing, they may be better c olonizers[4] Under these circumstances, local allopatry may eventually evolve to regional allopatry and have a biogeographical effect, affecting the distribution pattern of cytotypes and their various adaptations[12]. The question of what drives the shifts in range between diploid and polyploid relatives remains open

Methods

Results

Discussion

Conclusion