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玉米叶面积大小及分布对玉米的有效光吸收、干物质积累和产量的形成有重要作用,探究玉米不同叶位叶面积的遗传机理对高产玉米新品种的选育具有重要意义。本研究以两个叶面积差异显著的自交系为亲本组配了含有259个单株的F2群体;以此群体为作图群体,构建了一张总长1 735.1 c M的遗传连锁图谱,该图谱包含218个SSR标记,平均图距7.96 c M。用复合区间作图法(CIM)对玉米9片叶叶面积(穗上4片叶,穗位叶,穗下4片叶)分别进行了QTL定位分析,共定位到36个叶面积QTL,主要分布于第1、2、3和5染色体上,且控制不同叶位叶面积的QTL有集中分布现象。在第2和5染色体上定位到7个贡献率大于10%的QTL,第2染色体phi090-umc1256标记区间内的3个QTL位点可解释穗上3片叶的表型变异分别为12.7%、13.1%和11.1%;第5染色体umc1563-umc2301标记区间内的4个QTL位点可解释穗位叶及穗下第2、3、4叶的表型变异分别为15.4%、13.1%、12.3%和10.4%;这两个标记区间可能是调控玉米叶面积的重要区段。研究结果有助于进一步探究玉米不同叶位叶面积的遗传机制。
The size and distribution of maize leaf area play an important role in the effective light absorption, dry matter accumulation and yield formation of maize. Studying the genetic mechanism of maize leaf area at different leaf positions is of great significance to the breeding of new high yielding maize varieties. In this study, F2 population with 259 single plants was inbred using two inbred lines with significant differences in leaf area. The population was taken as a mapping population and a genetic linkage map with a total length of 1 735.1 cM was constructed. The map contains 218 SSR markers with an average distance of 7.96 cM. QTL mapping of nine leaf areas (4 leaves on the ear, 4 ears on the ear, 4 leaves on the ear) was performed by composite interval mapping (CIM), and the QTLs for 36 leaf areas were mapped, Distributed on chromosomes 1, 2, 3 and 5, and the QTLs controlling leaf area at different leaf positions were concentrated. Seven QTLs with more than 10% contribution were located on chromosomes 2 and 5, and three QTLs within the marker interval phi090-umc1256 on chromosome 2 explained 12.7% of the phenotypic variation of the three leaves on panicle, 13.1% and 11.1%, respectively. The four QTLs in the marker interval of umc1563-umc2301 on chromosome 5 explained 15.4%, 13.1% and 12.3% of the phenotypic variation of leaves 2,3,4, And 10.4%, respectively. These two marker intervals may be important segments regulating maize leaf area. The results will help further explore the genetic mechanism of leaf area at different leaf positions in maize.