The male sterility(MS)line is a prerequisite for efficient production of hybrid seeds in rice,a self-pollinating species.MS line breeding is pivotal for hybrid rice improvement.Understanding the historical breeding tr...The male sterility(MS)line is a prerequisite for efficient production of hybrid seeds in rice,a self-pollinating species.MS line breeding is pivotal for hybrid rice improvement.Understanding the historical breeding tra-jectory will help to improve hybrid rice breeding strategies.Maternally inherited cytoplasm is an appro-priate tool for phylogenetic reconstruction and pedigree tracing in rice hybrids.In this study,we analyzed the cytoplasmic genomes of 1495 elite hybrid rice varieties and identified five major types of cytoplasm,which correspond to different hybrid production systems.As the cytoplasm donors for hybrids,461 MS lines were also divided into five major types based on cytoplasmic and nuclear genomic architecture.Spe-cific core accessions cooperating with different fertility-associated genes drove the sequence divergence of MS lines.Dozens to hundreds of convergent and divergent selective sweeps spanning several agro-nomic trait-associated genes were identified among different types of MS lines.We further analyzed the cross patterns between different types of MS lines and their corresponding restorers.This study system-atically analyzed the cytoplasmic genomes of rice hybrids revealed their relationships with nuclear ge-nomes of MS lines,and illustrated the trajectory of hybrid rice breeding and the strategies for breeding different types of MS lines providing new insights for future improvement of hybrid rice.展开更多
基金supported by grants from the National Natural Science Foundation of China(31788103)the Chinese Academy of Sciences(XDB27010301).
文摘The male sterility(MS)line is a prerequisite for efficient production of hybrid seeds in rice,a self-pollinating species.MS line breeding is pivotal for hybrid rice improvement.Understanding the historical breeding tra-jectory will help to improve hybrid rice breeding strategies.Maternally inherited cytoplasm is an appro-priate tool for phylogenetic reconstruction and pedigree tracing in rice hybrids.In this study,we analyzed the cytoplasmic genomes of 1495 elite hybrid rice varieties and identified five major types of cytoplasm,which correspond to different hybrid production systems.As the cytoplasm donors for hybrids,461 MS lines were also divided into five major types based on cytoplasmic and nuclear genomic architecture.Spe-cific core accessions cooperating with different fertility-associated genes drove the sequence divergence of MS lines.Dozens to hundreds of convergent and divergent selective sweeps spanning several agro-nomic trait-associated genes were identified among different types of MS lines.We further analyzed the cross patterns between different types of MS lines and their corresponding restorers.This study system-atically analyzed the cytoplasmic genomes of rice hybrids revealed their relationships with nuclear ge-nomes of MS lines,and illustrated the trajectory of hybrid rice breeding and the strategies for breeding different types of MS lines providing new insights for future improvement of hybrid rice.
