Adaptive significance of flowering time variation across natural seasonal environments in Arabidopsis thaliana

第一作者：Alexandre Fournier-Level

第一单位：澳大利亚墨尔本大学

第一通讯：Alexandre Fournier-Level

 Abstarct 

背景回顾：The relevance of flowering time variation and plasticity to climate adaptation requires a comprehensive empirical assessment. 

植物开花时间变异与其对气候适应的可塑性之间的关联需要一个综合性的实验评估。

主要研究：We investigated natural selection and the genetic architecture of flowering time in Arabidopsis thaliana through field experiments in Europe across multiple sites and seasons. We estimated selection for flowering time, plasticity and canalization. 

本文中，作者基于欧洲多个地点和季节的大田试验，研究了拟南芥开花时间的自然选择和遗传结构。作者估计了开花时间、可塑性以及渠化（即随机变异减少）的选择。

结果1-早花选择：Loci associated with flowering time, plasticity and canalization by genome-wide association studies (GWAS) were tested for a geographic signature of climate adaptation. Selection favored early flowering and increased canalization except in the northernmost site, but was rarely detected for plasticity. GWAS revealed significant associations with flowering traits and supported a substantial polygenic inheritance. 

对于通过全基因组关联研究（GWAS）鉴定到的与开花时间、可塑性和渠化相关的基因位点，作者进一步测试了其气候适应的地理信号。除了最北边的试验地点，选择有利于提前开花和增加渠化，但很少能检测到可塑性。GWAS揭示了与开花性状相关的显著性关联，结果表明控制开花性状是大量的多基因遗传。

结果2-晚花相关位点：Alleles associated with late flowering, including functional FRIGIDA variants, were more frequent in regions experiencing high annual temperature variation. 

包括功能性FRIGIDA变体在内的与晚花相关的等位基因，在年气温变异较大的地区出现的更为频繁。

结果3-秋季开花：Flowering time plasticity to fall vs. spring and summer environments was associated with GIGANTEA SUPPRESSOR 5 which promotes early flowering under decreasing daylength and temperature. 

与春夏环境相比，开花时间在秋季的可塑性与GIGANTEA SUPPRESSOR 5基因相关，该基因在日长和温度降低的条件下促进早花。

结论：The finding that late flowering genotypes and alleles are associated with climate is evidence for past adaptation. 

晚花表型以及与气候相关的等位基因是拟南芥发生过适应性演化的证据。

拓展：Real-time phenotypic selection analysis, however, reveals pervasive contemporary selection for rapid flowering in agricultural settings across most of the species range. Response to this selection may involve genetic shifts in environmental cuing compared to the ancestral state.

然而，实时表型选择分析显示在大多数物种中，在农业环境下快速开花是普遍的当代选择。与祖先状态相比，对于该选择的响应可能涉及到了对于环境信号的遗传转变。

doi: https://doi.org/10.1111/nph.17999

Journal: New Phytologist

Published date: January 28, 2022