为阐明粳稻株高动态发育遗传基础,在南京和泗洪3个环境下种植粳稻品种秀水79和C堡及其杂交衍于生的254个重组自交家系,利用混合线性模型和最佳线性无偏预测方法对3个环境下不同时期株高变异的各效应值进行估计,进而利用非条件和条件QTL定位的方法对控制株高性状的静态值点和动态值点进行了检测。结果表明,3个环境中RIL群体各期株高均呈正态分布并出现双向超亲分离。株高受环境的影响随发育进程而不断减小。成熟期检测到5个QTL,其中qPH8.3仅在该时期检测到。采用非条件定位的方法共检测到15个非条件加性QTL。不同时期检测到的同一加性位点,增效等位基洲来一于同一亲本,加性效应的大小随着发育进程而增大。条件定位的方法共检测到16个条件加性QTL和16个互作位点对,6个加性QTL在不同的两个时间段检测到,其余位点(位点对)均枉单个时期检测到。从播种至移栽后42d、移栽后56d至70d以及移栽后98d至112d这3个时间段,株高性状以加性遗传效应为主;移栽后42d至56d以及移栽后70d至84d这两个时间段受加性效应和上位性效应共州控制;而移栽后84d至9d则以上位性遗传效应为主。G×E互作遗传效应仁整个调查时期均很小。多环境条件下两种定位方法的结合有助于更全面地了解株高在不同发育时期的遗传基础。
To understand the genetic: basis of dynamic development of plant height in japonica rice, the static and dynamlc loci for the trant were detected by unconditional and conditional QTL mapping methods using a population of 254 recombinant inbred lines derived from.the cross between Xiushui 79 and C Bao. Phenotypic wducs were investigated under three different errvironments and analyzed by the mixture-linear model. Normal distribution and transgressive segregation in both dircctions were observed in the RII. populations under three environments. The results indicated that the impact on plb.nt height caused by environment would be reduced with plant growth and development. Five QTI.s were detected at maturity stage, and qPH8.3 was unique at this stage. Fifteen unconditional additive QTLs were identified at nine developmental stages. The positive alleles of identical additive loci detected at different stages were originated from the same parent and the additive effects were increased with the plant growth. Sixteen conditional additive QTI.s and sixteen epistatic QTL pairs involved in plant height were identified at nine dynamic measurement stages. Among them, six additive QTI.s were detected at two stages, while the others were detected only at a stage. The additive effect was the major genetic effect at the three stages including from sowing to 42 d after transplanting, from 56 dafter transplanting to 70 dand from 98 dafter transplanting to 112 d. From 42 d after transplanting to 56 d and from 70 d to 84 d, plant height wets controlled both by additive and epistatic effects. Whereas epistatic was the major genetic effect from 84 d after transplanting to 98 d. Effect of G× E interaction was small during all developmental stages. Combining unconditional QTL mapping with conditional QTL mapping under muhienvironments is a promising strategy to elucidate the genetic basis of plant height at different development stages.