A novel procedure for identifying a hybrid QTL-allele system for hybrid-vigor improvement, with a case study in soybean(Glycine max)yield  

作　　者：Jinshe Wang Jianbo He Jiayin Yang Junyi Gai 

机构地区：[1]Soybean Research Institute/MARA National Center for Soybean Improvement/MARA Key Laboratory of Biology and Genetic Improvement of Soybean(General)/State Key Laboratory for Crop Genetics and Germplasm Enhancement/Jiangsu Collaborative Innovation Center for Modern Crop Production,Nanjing Agricultural University,Nanjing 210095,Jiangsu,China

出　　处：《The Crop Journal》2023年第1期177-188,共12页作物学报（英文版）

基　　金：supported by the National Key Research and Development Program of China (2021YFF1001204,2017YFD0101500);the MOE Program of Introducing Talents of Discipline to Universities (“111”Project, B08025);the MOE Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT_17R55);the MARA CARS-04 Program;the Jiangsu Higher Education PAPD Program;the Fundamental Research Funds for the Central Universities (KYZZ201901);the Jiangsu JCICMCP Program。

摘　　要：“Breeding by design” for pure lines may be achieved by construction of an additive QTL-allele matrix in a germplasm panel or breeding population, but this option is not available for hybrids, where both additive and dominance QTL-allele matrices must be constructed. In this study, a hybrid-QTL identification approach, designated PLSRGA, using partial least squares regression(PLSR) for model fitting integrated with a genetic algorithm(GA) for variable selection based on a multi-locus, multi-allele model is described for additive and dominance QTL-allele detection in a diallel hybrid population(DHP). The PLSRGA was shown by simulation experiments to be superior to single-marker analysis and was then used for QTL-allele identification in a soybean DPH yield experiment with eight parents. Twenty-eight main-effect QTL with 138 alleles and nine QTL × environment QTL with 46 alleles were identified, with respective contributions of 61.8% and 23.5% of phenotypic variation. Main-effect additive and dominance QTL-allele matrices were established as a compact form of the DHP genetic structure. The mechanism of heterosis superior-to-parents(or superior-to-parents heterosis, SPH) was explored and might be explained by a complementary locus-set composed of OD+(showing positive over-dominance, most often), PD+(showing positive partial-to-complete dominance, less often) and HA+(showing positive homozygous additivity, occasionally) loci, depending on the parental materials. Any locus-type, whether OD+, PD + and HA+, could be the best genotype of a locus. All hybrids showed various numbers of better or best genotypes at many but not necessarily all loci, indicating further SPH improvement. Based on the additive/dominance QTL-allele matrices, the best hybrid genotype was predicted, and a hybrid improvement approach is suggested. PLSRGA is powerful for hybrid QTL-allele detection and cross-SPH improvement.

关 键 词：Breeding by design Diallel hybrid population PLSRGA(partial least squares regression via genetic algorithm) QTL-allele matrix of additive/dominance effect Simulation experiment Soybean[Glycine max(L.)Merr.] 

分 类 号：S565.1[农业科学—作物学]