Rapid formation of stable autotetraploid rice from genome-doubled F1 hybrids of japonica–indica subspecies

作者：Xu Han, Jiahao Li, Guo Li, Zhibin Zhang, Taotao Lian, Bingqi Zhang, Ting Luo, Ruili Lv, Xiaojing Cai, Xiuyun Lin, Chunming Xu, Ying Wu, Lei Gong, Jonathan F. Wendel, Liu B · 发表于：Nature Plants · 年份：2025 · DOI：10.1038/s41477-025-01966-2 · 被引用次数：10 · 研究领域：Chromosomal and Genetic Variations、Genetic Mapping and Diversity in Plants and Animals、Plant Disease Resistance and Genetics

Theory predicts that in the absence of selection, a newly formed segmental allopolyploid will become 'autopolyploidized' if homoeologous exchanges (HEs) occur freely. Moreover, because selection against meiotic abnormalities is expected to be strong in the initial generations, we anticipate HEs to be uncommon in evolved segmental allopolyploids. Here we analysed the whole-genome composition of 202 phenotypically homogeneous and stable rice tetraploid recombinant inbred lines (TRILs) derived from Oryza sativa subsp. japonica subsp. indica hybridization/whole-genome doubling. We measured functional traits related to growth, development and reproductive fitness, and analysed meiotic chromosomal behaviour of the TRILs. We uncover factors that constrain the genomic composition of the TRILs, including asymmetric parental contribution and exclusive uniparental segment retention. Intriguingly, some TRILs that have high fertility and abiotic stress resilience co-occur with largely stabilized meiosis. Our findings comprise evidence supporting the evolutionary possibility of HE-catalysed 'allo-to-auto' polyploidy transitions in nature, with implications for creating new polyploid crops.