基于玉米永久性F2群体株型性状的灰色关联度分析及通径分析

Gray correlation and path analysis of plant type traits based on an immortalized F2 population in Maize

玉米株型性状是理想株型设计育种的基础,而株高是构建合理株型的重要因素.以优良玉米自交系PH6WC和郑58为亲本构建的291个F2家系为研究材料,对玉米株高、穗位高、穗上高、雄穗长、穗上节间数、穗上平均节间长等株型性状分别进行灰色关联度分析和通径分析.灰色关联度分析表明,穗上高与株高的关联度最大,其关联度为0.836;其次为穗上平均节间长与穗上高,关联度为0.825;株高与雄穗长关联度最小,为0.702.通径分析表明,穗上高对株高直接作用最大,其直接通径系数为0.717;穗上平均节间长通过穗上高对株高的间接作用最大,其间接通径系数为0.674.因此,在对玉米株型进行选择时,要注重对穗上高、穗位高和穗上平均节间长的控制,适当放宽对穗上节间数和雄穗长的控制,可为玉米理想株型的选育提供理论参考.

Maize plant type traits is the basis for the design of ideal plant type breeding,and plant height is an important factor in constructing reasonable plant type.In this study,291 immortalized F2 families derived from PH6WC and Zheng 58 were used as research materials,plant type traits(plant height,ear height,plant height above ear,tassel length,internode number above ear,and average internode length above ear)were performed for gray correlation and path analysis.Gray correlation analysis showed that the correlation degree between plant height above ear and plant height was the highest(0.836),followed by the average internode length above ear and plant height above ear(0.825),and the lowest correlation degree was plant height and tassel length(0.702).Path analysis showed that plant height above ear had the most direct effect on plant height,and its direct path coefficient was 0.717.The indirect effect of average internode length above ear on plant height was the largest by plant height above ear,and the combined indirect coefficient was 0.674.As a result,it should be paid more attention to plant height above ear,ear height and average internode length above ear,and it should be broaden to internode number and tassel length.The results of this study can provide theoretical reference for the breeding of ideal plant type in maize.