Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, 41080-Sevilla, Spain.
J Exp Bot. 2021 Jul 28;72(15):5522-5533. doi: 10.1093/jxb/erab179.
Whole-genome duplication and post-polyploidization genome downsizing play key roles in the evolution of land plants; however, the impact of genomic diploidization on functional traits still remains poorly understood. Using Dianthus broteri as a model, we compared the ecophysiological behaviour of colchicine-induced neotetraploids (4xNeo) to diploids (2x) and naturally occurring tetraploids (4xNat). Leaf gas-exchange and chlorophyll fluorescence analyses were performed in order to asses to what extent post-polyploidization evolutionary processes have affected 4xNat. Genomic diploidization and phenotypic novelty were evident. Distinct patterns of variation revealed that post-polyploidization processes altered the phenotypic shifts directly mediated by genome doubling. The photosynthetic phenotype was affected in several ways but the main effect was phenotypic diploidization (i.e. 2x and 4xNat were closer to each other than to 4xNeo). Overall, our results show the potential benefits of considering experimentally synthetized versus naturally established polyploids when exploring the role of polyploidization in promoting functional divergence.
全基因组复制和多倍体化后基因组缩小在陆地植物的进化中起着关键作用；然而，基因组二倍化对功能性状的影响仍知之甚少。本文以香石竹（Dianthus broteri）为模型，比较了秋水仙素诱导的同源四倍体（4xNeo）与二倍体（2x）和自然发生的四倍体（4xNat）的生态生理行为。为了评估多倍体化后进化过程在何种程度上影响了 4xNat，我们进行了叶片气体交换和叶绿素荧光分析。基因组二倍化和表型新颖性是明显的。不同的变异模式表明，多倍体化后过程改变了由基因组加倍直接介导的表型变化。光合作用表型受到多种方式的影响，但主要影响是表型二倍化（即 2x 和 4xNat 彼此更接近，而不是与 4xNeo 接近）。总的来说，我们的研究结果表明，在探索多倍化在促进功能分化中的作用时，考虑实验合成的多倍体与自然建立的多倍体具有潜在的好处。
