甘蓝型油菜遗传图谱的构建及单株产量构成因素的QTL分析

Molecular mapping and identification of quantitative trait loci for yield components in rapeseed (Brasscia napus L.)

采用常规品系04-1139与高产多角果品系05-1054构建的F2代群体为作图群体,运用SSR(Simple sequence repeat)和SRAP(Sequence-related amplified polymorphism)构建分子标记遗传图谱并对甘蓝型油菜单株产量构成因素进行QTL分析。遗传图谱包含200个分子标记,分布于19个连锁群上,总长度1700.23cM,标记间的平均距离8.50cM。采用复合区间作图法(Composite interval mapping,CIM)对单株产量构成因素(单株有效角果数、每果粒数和千粒重)进行QTL分析,共检测到12个QTL:其中单株有效角果数4个QTL,分别解释表型变异为35.64%、12.96%、28.71%和34.02%;每果粒数获得5个QTL,分别解释表型变异为8.41%、7.87%、24.37%、8.57%和14.31%;千粒重获得3个QTL,分别解释表型变异为2.33%、1.81%和1.86%。结果表明:同一性状的等位基因增效作用可以同时来自高值亲本和低值亲本;文章中与主效QTL连锁的标记可用于油菜产量性状的分子标记辅助选择和聚合育种。

A F2 segregating population for genetic map construction and identification of QTL for seed yield in rapeseed （Brassica napus L.）,was developed via crossing a conventional rapeseed line 04-1139 with a high yielding multiple silique rapeseed line 05-1054.A genetic map including 19 linkage groups was constructed with 200 SSR （Simple sequence repeat） and SRAP （Sequence-related amplified polymorphism） markers.This map covers a total length of 1 700.23 cM with an average distance between two adjacent makers of 8.50 cM.Using this map,QTL for the components of yield per plant,such as number of silique per plant （SNP）,number of seeds per silique （SS） were analyzed.A total of 12 putative QTL for the traits were detected.Four of them were associated with SNP,which explained 35.64%,12.96%,28.71%,and 34.02% of the variation,respectively.Five QTL,which explained 8.41%,7.87%,24.37%,8.57%,and 14.31% of the variation,were responsible for SS.Three QTL for 1 000-seed weight explained 1.81%~2.33% of the variation.The additional effects of the alleles for a trait may originate from both parents.The markers associated with the main QTL can be a good tool for marker associated selection and pyramiding breeding.