Chromosome stability and genetic characteristics of a novel allohexaploid Brassica developed by selfing of microspore-derived lines
作者单位：Institute of Crop Science and Zhejiang Key Laboratory of Crop GermplasmZhejiang University
会议名称：《中国作物学会油料作物专业委员会第八次会员代表大会暨学术...》
会议日期：2018年
学科分类：0710[理学-生物学] 07[理学] 071007[理学-遗传学]
关 键 词：allohexaploid Brassica chromosome stability genetic characteristics SNP QTL mapping
摘 要：In Brassica,only three diploid species and three allotetraploid species exist in nature.The synthesis of novel allohexaploid Brassica with A,B,C genomes would be a long-term goal in Brassica genetics and play an important role in crop breeding and genetic studies.In this investigation,we self-crossed a doubl haploid(DH)population obtained from microspore culture of an allohexaploid F((HI6-1) from the cross between two recently-synthesized allohexaploid Brassica lines.Plant morphology,chromosome number,plant ploidy,pollen activity,yield and quality traits were studied,tending to select the progenies with stable chromosomes and good characters.In addition,we used single nucleotide polymorphism(SNP) genetic variation based on restriction site-related DNA(RAD) sequencing to construct a high-density genetic linkage map of the population(including parents and146 DH progenies).As a result,a genetic map of this allohexaploid Brassica DH population was constructed with7 950 high quality SNP markers,which segregated normally(1:1) in the population.The linkage map contained all 27 chromosomes from the parental A,B and C genomes with a total genetic distance of 5 725.19 cM and an average of 0.75 cM between adjacent markers.We detected 5 fertility-related traits associated with 25 additive QTLs.Moreover,44 intra-genomic and 18 inter-genomic epistatic QTL pairs were detected for 4 phenotypic traits.Phenotypic,phenological parameters as well as yield components and quality traits were also investigated and compared between different generations.The results provide a foundation for improving stability and fertility in a future allohexaploid Brassica species.