不同发育阶段大豆株高和茎粗QTL的动态分析

Dynamic Analysis of QTL for Plant Height and Stem Diameter at Different Developmental Stages in Soybean

利用中豆29×中豆32的重组自交系,以复合区间作图法对不同发育阶段的大豆株高和茎粗同时进行非条件和条件QTL定位,在11个连锁群检测到18个株高QTL,在9个连锁群检测到19个茎粗QTL。不同发育时期影响大豆株高和茎粗QTL的数量、加性效应和贡献率均不相同,QTL表达具有时序性和选择性,有些QTL仅表达1次,有些可多次连续表达。有3个株高QTL和1个茎粗QTL在3个年度重复表达,有6个株高QTL和2个茎粗QTL在2个年度重复表达。F连锁群上株高和茎粗QTL存在共位性,R1～R4期均有株高和茎粗QTL同时表达,但株高和茎粗QTL的增效基因不同,株高QTL表达次数多而茎粗QTL表达次数较少,前期(V4～R3)QTL表达数量多而后期(R4～R5)表达数量较少。株高和茎粗QTL的动态变化与表型相关分析结果一致,对于适期选择粗秆抗倒的高产材料具有指导作用。

Plant height and stem diameter are important agronomic traits in soybean,which have effect on yield and lodging.The objective of this study was to molecularly map the QTL conditioning plant height and stem diameter at different developmental stages of soybean growth.A population of 165 recombinant inbred lines（RILs） derived from a cross between Zhongdou 29 and Zhongdou 32 was used in this study.Based on unconditional and conditional QTL mapping methods,18 QTLs for plant height and 19 QTLs for stem diameter were detected on eleven and nine linkage groups respectively.The number,additive effects and contribution rate of QTLs for plant height and stem diameter were different at different developmental stages,which indicated that these QTLs expressed timely and selectively.Three QTLs for plant height and one QTL for stem diameter were detected in three years,and six QTLs for plant height and two QTLs for stem diameter were detected in two years.The QTLs of plant height and stem diameter on linkage groups F were mapped to the same loci and they were expressed simultaneously from R1 to R4 stages.Compared with the late stages,more QTLs expressed in the early stages,and QTLs for plant height expressed more times than QTLs for stem diameter.The positive alleles of QTLs for plant height and stem diameter were fromdifferent parents.The developmental dynamic of QTLs for plant height and stem diameter was consistent with the correlation analysis of phenotypic traits at different developmental stages.