玉米遗传连锁图谱加密及粗缩病抗性QTL定位

目的]加密玉米SSR遗传连锁图谱,对玉米粗缩病抗性QTL进行精确定位分析。方法]以(80007×80044)F9∶10为作图群体,在实验室前期建立的SSR遗传图谱基础上,将检测到的新的87个标记加密到遗传图谱中,最终构建包括260个位点的遗传连锁图谱;同时将RIL群体衍生的195个F9∶10家系进行田间抗病性状鉴定,采用完备区间作图方法(ICIM)对玉米粗缩病抗性进行QTL的定位分析。结果]图谱总长度1 170 cm,标记间平均距离4.50 cm;在济宁环境条件下定位到1个QTL,表型变异贡献率为9.57%,可作进一步的精细定位和克隆。结论]该试验对玉米粗缩病抗性QTL进行了精确定位分析,为玉米SSR遗传连锁图谱研究提供了依据。

Increasing Density of Genetic Linkage Map and Identification of a QTL for Resistance to Maize Rough Dwarf Disease

Objective ] To increase density of maize SSR genetic linkage map, QTL for resistance to maize rough dwarf disease was identified. Method] A mapping population consisting of 195 Fg= 10 recombinant inbred lines（RILs） derived from the cross between maize inbred lines 80007 and 80044 was used in this study. Based on the genetic linkage map in our laboratory, 117 pairs of markers were screened polymorphism between the parents in 430 pairs of new SSR markers, and 87 pairs of these were used to increase density of genetic linkage map. The final map included 260 polymorphic SSR markers. Result] The total genetic length was 1 170 cm with an average interval distance of 4.50 cm. One QTL for MRDD was identified in Jining environment, explaining 9.57% of the phenotypic variation, which could be used for fining mapping and position- al cloning. Conclusion] QTL for resistance to maize rough dwarf disease was identified and analyzed, which will provide basis for study on maize SSR genetic linkage map.