Fixation of hybrid sterility genes and favorable alleles of key yield-related genes with dominance contribute to the high yield of the Yongyou series of intersubspecific hybrid rice  

作　　者：Pengfei Wang Feixiang Qi Honglin Yao Xingbing Xu Wenjun Li Jianghu Meng Qinglu Zhang Weibo Xie Yongzhong Xing 

机构地区：[1]National Key Laboratory of Crop Genetic Improvement,Huazhong Agricultural University,Wuhan,Hubei 430070,China [2]Hubei Hongshan Laboratory,Wuhan,Hubei 430070,China

出　　处：《Journal of Genetics and Genomics》2022年第5期448-457,共10页遗传学报（英文版）

基　　金：partially supported by funds from the National Natural Science Foundation of China (32061143042, 31821005, 91935302);The National Key Research and Development Program of China(2016YFD0100802)

摘　　要：In rice,the Yongyou series of Xian-Geng intersubspecific hybrids have excellent production performance,as shown by their extremely high yield.However,the mechanisms underlying the success of these rice hybrids are unclear.In this study,three F2 populations are generated from three Yongyou hybrids to determine the genetic basis of the extremely high yield of intersubspecific hybrids.Genome constitution analysis reveals that the female and male parental lines belong to the Geng and Xian subspecies,respectively,although introgression of 20%of the Xian ancestry and 14%of the Geng ancestry are observed.Twenty-five percent of the hybrid genomes carries homozygous Xian or Geng fragments,which harbors hybrid sterility genes such as Sd,Sc,f5,and q S12 and favorable alleles of key yield-related genes,including NAL1,Ghd7,and Ghd8.None of the parents carries the S5+killer of the S5 killer-protector system.Compatible allele combinations of hybrid sterility genes ensure the fertility of these intersubspecific hybrids and overcome the bottleneck in applying intersubspecific hybrids.Additive effects of favorable alleles of yield-related genes fixed in both parents enhances midparent values.Many QTLs for yield and its key component spikelets per panicle shows dominance and the net positive dominant effects lead to heterosis.These factors result in an extremely high yield of the hybrids.These findings will aid in the development of new intersubspecific rice hybrids with diverse genetic backgrounds.

关 键 词：Intersubspecific hybrid HETEROSIS FERTILITY INTROGRESSION Favorable alleles DOMINANCE 

分 类 号：S511[农业科学—作物学]