Regional differences in the abiotic environment contribute to genomic divergence within a wild tomato species
Regional differences in the abiotic environment contribute to genomic divergence within a wild tomato species
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DOI：
10.1111/mec.15477
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发表时间：
2020-06-09
影响因子：
4.9
通讯作者：
Moyle, Leonie C.
中科院分区：
文献类型：
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作者：
Gibson, Matthew J. S.;Moyle, Leonie C.
野生加仑番茄在厄瓜多尔和秘鲁的原生范围内广泛栖息于非生物栖息地。虽然它已成为国内品种改良的关键遗传资源，但对该物种本地适应的遗传基础知之甚少，也不知道哪些非生物变量对驱动分化最重要。本研究利用冗余分析（RDA）和其他多元统计方法（结构方程模型（SEM）和广义不相似性模型（GDM））量化了140个野生种质的基因组变异（6,830个单核苷酸多态性[SNPs]）与气候和地理的关系。RDA、SEM和GDM均认为环境比地理更能解释基因组变异，这表明对异质非生物栖息地的局部适应可能是该物种遗传多样性的重要来源。描述降水和蒸发需求的时间变化的环境因子解释了物种间SNP的大部分变化，表明这些力量可能是关键的选择因子。最后，通过研究snp -环境关联如何在整个基因组（44,064个snp）中变化，我们绘制了位点的位置并调查了对气候适应有贡献的位点的功能。总之，我们的研究结果表明，非生物环境施加的选择在推动种群之间的基因组分化中起着重要作用。
The wild currant tomato Solanum pimpinellifolium inhabits a wide range of abiotic habitats across its native range of Ecuador and Peru. Although it has served as a key genetic resource for the improvement of domestic cultivars, little is known about the genetic basis of traits underlying local adaptation in this species, nor what abiotic variables are most important for driving differentiation. Here we use redundancy analysis (RDA) and other multivariate statistical methods (structural equation modelling [SEM] and generalized dissimilarity modelling [GDM]) to quantify the relationship of genomic variation (6,830 single nucleotide polymorphisms [SNPs]) with climate and geography, among 140 wild accessions. RDA, SEM and GDM each identified environment as explaining more genomic variation than geography, suggesting that local adaptation to heterogeneous abiotic habitats may be an important source of genetic diversity in this species. Environmental factors describing temporal variation in precipitation and evaporative demand explained the most SNP variation among accessions, indicating that these forces may represent key selective agents. Lastly, by studying how SNP-environment associations vary throughout the genome (44,064 SNPs), we mapped the location and investigated the functions of loci putatively contributing to climatic adaptations. Together, our findings indicate an important role for selection imposed by the abiotic environment in driving genomic differentiation between populations.