剖析杂种群体产量性状的遗传基础,确定候选基因对分子作物育种具有重要意义。在这项研究中,aBC1F3:4人口,系本身(LPS)种群,以优良自交系Zhing58和PH4CV为亲本构建。用55,000个SNP对种群进行基因分型,并与Chang7-2和PH6WC(两个测试人员)进行测试杂交,以构建两个测试交叉(TC)种群。在多种环境中评估了三个种群的百粒重(HKW)和单株产量(YPP)。标记性状关联分析(MTA)在三个种群中鉴定出24至151个重要的SNP。在LPS和TC群体中鉴定出常见和特定数量性状基因座/基因座(QTL)的显著SNP的比较。对这些显著SNP的遗传特征分析证明,这些SNP与测试性状相关,可用于预测LPS和TC群体的性状表现。使用玉米杂交品种及其亲本进行RNA-seq分析,并鉴定了杂种品种和亲本系之间的差异表达基因(DEGs)。将DEGs的染色体位置与TC群体中检测到的重要SNP的染色体位置进行比较,确定了可能与杂种性能相关的潜在候选基因。结合RNA-seq分析和MTA结果确定了杂种表现的候选基因,提供可能对玉米杂交育种有用的信息。
Dissecting the genetic basis of yield traits in hybrid populations and identifying the candidate genes are important for molecular crop breeding. In this study, a BC1F3:4 population, the line per se (LPS) population, was constructed by using elite inbred lines Zheng58 and PH4CV as the parental lines. The population was genotyped with 55,000 SNPs and testcrossed to Chang7-2 and PH6WC (two testers) to construct two
testcross (TC) populations. The three populations were evaluated for hundred kernel weight (HKW) and yield per plant (YPP) in multiple environments. Marker-trait association analysis (MTA) identified 24 to 151 significant SNPs in the three populations. Comparison of the significant SNPs identified common and specific quantitative trait locus/loci (QTL) in the LPS and TC populations. Genetic feature analysis of these significant SNPs proved that these SNPs were associated with the tested traits and could be used to predict trait performance of both LPS and TC populations. RNA-seq analysis was performed using maize hybrid varieties and their parental lines, and differentially expressed genes (DEGs) between hybrid varieties and parental lines were identified. Comparison of the chromosome positions of DEGs with those of significant SNPs detected in the TC population identified potential candidate genes that might be related to hybrid performance. Combining RNA-seq analysis and MTA results identified candidate genes for hybrid performance, providing information that could be useful for maize hybrid breeding.