玉米八个产量相关性状的QTL鉴定

QTL mapping of eight yield-relative traits in maize

以玉米优良自交系‘农系531’和‘SIL8’为亲本构建200个F2:3家系,利用复合区间作图法对8个产量性状进行QTL鉴定。8个性状共检测到34个QTL,单个QTL的表型贡献率为5.21%～26.62%不等,累计解释各个性状的表型变异为21.33%～74.10%。分布于第1、3、4、5、6染色体上16个QTL形成6个QTL富集区,且表型贡献率最大的QTL均位于富集区内。共检测到26对上位性互作,其中QTL间互作1对,QTL与背景间互作8对,背景间互作17对,所解释的表型变异为5.98%～15.93%不等,累计解释各性状的表型变异为15.93%～61.64%。多数产量相关性状的遗传基础非常复杂,上位性在产量相关性状形成的遗传控制中具有重要的作用。QTL富集区对于数量性状的遗传分析与作物遗传改良具有重要意义。

A F2.3 population composing 200 families was developed from the combination of NX531×SIL8. The composite interval mapping （CIM） method was used to identify QTL and significant interaction pairs for the eight yield-relative traits. A total of 34 QTL for the eight traits was detected, each QTL explained phenotypic variation from 5. 21% to 26. 62%, and the accumulative phenotypic variation explained by QTL for single trait was from 21.33% to 74.10 %. Sixteen QTL detected were mapped in six QTL clusters on chromosome 1,3,4,5 and 6. Those QTL with the large phenotype contribution for certain trait were located in the QTL clusters. In addition, 26 epistatic QTL pairs were identified including only 1 pair QTL x QTL interaction. The phenotypic variation explained by single interaction pair ranging from 5.98 % to 15.93%, accumulatively from 15. 93% to 61. 64% for single trait. Most of yield-relative traits display a complex genetic basis and epistasis play a key role in the genetic controlling of yield-associated traits of maize. The detected QTL clusters could provide valuable information for gene cloning and genetic improvement to maize yield-relative traits.