小麦株高相关性状的QTL分析

Mapping Quantitative Trait Loci for Plant Height Related Characteristics in Wheat

为探索小麦株高及其相关构成性状的遗传基础,以小麦品系＂0911-46＂与品系＂42＂杂交获得的F2及其衍生F2∶3群体为材料,应用SSR标记构建连锁图谱,在杨凌和乾县2种环境条件下对株高、穗下节长、基部第Ⅰ节长、基部第Ⅱ节长进行QTL定位研究。结果表明：所构建的连锁遗传图谱覆盖小麦全基因组的1 423.54cM,标记间的平均遗传距离为8.09cM。共检测到47个QTLs,涉及小麦1A、1D、2A、2B、2D、3A、4B、4D、5A、5B、5D、6B、6D、7A、7B、7D染色体。其中,有16个株高QTL,15个穗下节长QTL,8个基部第Ⅰ节长QTL,8个基部第Ⅱ节长QTL,单个QTL可解释0.29%-63.42%的表型变异。4D染色体上Xwmc473-Xwmc285标记区间内距Xwmc473标记2.07cM处,在F2和F2∶3的2种环境中都能检测到株高QTL,表现出世代间和环境稳定性。此外,在该标记区间还能同时检测到分别控制株高、穗下节长、基部第Ⅰ节长、基部第Ⅱ节长的QTL,表明这一标记区间是一个株高及其构成性状QTL富集区。

This study aimed to detect quantitative trait loci（QTLs）controlling plant height characteristics,namely plant height（PH）,the first internode length counted from the top（TL1）and the internodes lengths from the first to the second counted from the ground（GL1、GL2）,by using two populations（F2and F2∶3）derived from the cross between line＂0911-46＂and line＂42＂grown in Yangling（YL）and Qianxian（QX）.A linkage map was constructed with 176SSR makers covering the whole wheat genome with a total length of 1 423.54cM and an average distance of 8.09cM between makers.A total of 47QTLs for plant height related characteristics were found on 1A,1D,2A,2B,2D,3A,4B,4D,5A,5B,5D,6B,6D,7A,7Band 7Dchromosomes,respectively.During these QTLs,there were 16QTLs for plant height,15QTLs controlling TL1,8QTLs for GL1and 8QTLs for GL2,and individual QTL could explain 0.29%-63.42% of the phenotypic variations.In the interval between markers Xwmc473and Xwmc285on chromosome 4Dwith genetic distances of 2.07cM from marker Xwmc473,QTL for PH were detected in both population of F2and F2∶3（YL and QX）,which showedstability of this QTL.In the same interval,QTLs for TL1,GL1and GL2were detected as well,which showed this marker interval was a gene cluster for plant height related traits.