大粒型水稻材料粒型性状的QTL定位

研究大粒型水稻材料对粒型相关基因的挖掘具有重要作用,同时也能为水稻超高产育种提供优质的种质资源。本研究以大粒型水稻材料lg1与9311杂交衍生的F2遗传分离群体为对象,分别采用2014年、2015年的粒型数据和2年的联合粒型数据,对控制其粒长、粒宽及粒厚的QTL进行初步定位。结果表明,3种情况下共定位到22个相关QTL,其中5个粒长QTL、9个粒宽QTL、8个粒厚QTL,分布于第1、第2、第3、第4、第5、第8和第11号染色体上。3种情况下均检测到QTL的有3个,即粒长QTL q GL-2-1、粒宽QTL q GW-5-1和粒厚QTL q GT-5-1,3个QTL增效等位基因均来自于亲本lg1;此外,有7个QTL在2014年、2015年和2年的联合数据定位中均被检测到,12个QTL只在1年或2年的联合数据定位中被检测到。q GL-2-1、q GW-2-3和q GT-2-3处于同一标记区间RM5812~RM13174,推测可能受同一粒型基因控制,是新的粒型QTL位点。主效QTL q GL-1-2和q GW-11-1可能是新的控制粒型QTL位点,其余检测到的QTL所在的大部分标记区间已有粒型QTL被定位或克隆。本研究结果为大粒水稻lg1粒型基因的精细定位及克隆奠定了基础。

Identification of QTLs for Rice Grain Shape Traits for a Large Grain Material

The study of the large grain material plays an important role in mining genes of grain shape trait,and can provide high quality germplasm resources for rice breeding.In this study,The F2 segregation population,which was derived from a cross between large grain material lg1 and indica variety 9311,was used to identify QTL with the data of the grain shape traits in 2014,2015 and the combined data of two years,respectively.The results showed that 22 QTLs were detected on chromosome No.1,2,3,4,5,8 and 11,including 5 QTLs for grain length,9 QTLs for grain width,and 8 QTLs for grain thickness.There were 3 QTLs detected repeatedly in three situations,including grain length QTL qGL-2-1,grain width QTL qGW-5-1 and grain thickness QTL qGT-5-1,whose alleles were derived from parent lg1.In addition,7 QTLs were identified in two situations,and 12 QTLs were identified only in one situation.The qGL -2-1,qGW-2-3 and qGT-2-3 were located in the same interval RM5812-RM13174,indicating that they could be influenced by one gene which might be a new grain shape gene.The major QTLs qGL-1-2 and qGW-11-1 could be new QTL loci of grain shape trait.Most of the rest QTLs are cloned gene and some mapped QTLs.These results have built a foundation for further fine mapping and cloning genes of lg1 grain shape traits.