QTL Analysis For Maize Kernel Quality Traits Using Four RILs Applied In Different Period

Maize quality related traits,not only mainly determine the grain yield,but are also associated with the nutrition of maize.In the long term maize breeding,these traits have not been focused on breeding.Givenin their importance in maize development and production,researchers have conducted numerous of genetics and molecular studies in these traits on different levels.However,associated regulatory mechanisms underlying them were not fully understood.Employing QTL mapping to dissect these important traits,will be in favor for identifying their possible regulatory genes.In the present study,four elite hybrids in Chinese modern maize breeding were selected to construct RIL populations.Then,these four RIL populations were used for identifying QTL for maize kernel starch,protein and oil content..1.In the present study,four hybrids,including Zhongdan2,Danyu13,Yedan13,Zhengdan958,were employed as the basic materials.And,GBS was used to genotype each line of the seven RIL populations.Then,the linkage maps,constructed by genotypic informations of the four RIL populations,contain 2241~3217 reconbination bins with total length ranging from 2241.2~2781c M.2.Phenotypic analysis of the measured triats revealed that maize kernel protein content grandually reduced,and maize kernel starch content grandually increased.However,oil content measured in the four RIL populations have not shown special trends.3.Using different QTL mapping methodologies,63 QTL were identified for kernel starch,protein,oil content.Through comparing results of different QTL methods,,we identified 7 major QTLs of starch content,q STA2-1?q STA2-2?q STA5-1?Jq STA5?q STA8-3?q STA8-4?q STA7-1.10 protein QTL : q PRO3-1?q PRO3-2?q PRO4-1?q PRO4-2?Jq PRO8?q PRO8-2?Jq PRO9-2?Jq PRO9-1?q PRO9-1?q PRO9-2.4 oil content QTL: q OIL1-1?q OIL1-2?q OIL5-3?q OIL9.