14个青贮玉米自交系抗根倒伏性状的配合力效应及通径分析

摘要

选用福建省农业科学院作物研究所选育的9个青贮玉米自交系以及5个不同杂优类群的自交系,按NCⅡ(不完全双列杂交)设计的原理和方法对组配的45个杂组合的倒伏率、株高、穗位高、茎粗、入土根数、根冠直径等9个性状进行配合力分析,并进行相关及通径分析.结果表明:母本组中交51抗倒性较差,478抗倒性好；父本组中MQ11-4抗倒性较差,MQ11-2、MQ11-7抗倒性较好；倒伏率的狭义遗传力h2N较高,表明对亲本抗倒性的选择,是进行抗倒性育种的有效途径.相关及通径分析表明:根倒伏与穗位高呈极显著负相关,与茎粗、入土根数、根冠直径呈极显著正相关,穗位高直接正向作用大,根冠直径直接负向作用大,抗倒性育种应注意这些性状的选择.%Nine silage maize inbred lines cultivated by the Crops Research Institute at Fujian Academy of Agricultural Sciences and 5 inbred lines from different heterosis groups were selected for the study. Designed by using the PlxP2 uncompleted diallel crossing of NC1I method, the 14 inbred lines' combining abilities and correlations were evaluated. In addition, with the path analysis, 9 traits including the lodging rate, plant height, ear height, stem diameter, root number, root cap diameter and so on, were correlated. The results showed that (a) the female inbred lines of Ye478 had a desirable lodging resistance, but Jiao51 was poor in that regard) and (b) the male inbred lines of MQ11-2 and MQ11-7 were desirable on lodging resistance, but not MQ11-4. The hN2, for the lodging rate was high, indicating a possibility to effectively breed lodging resistance varieties through parental breeding. The stem diameter, root number and root cap diameter significantly correlated to the root lodging resistance, but the ear height showed a significant inverse correlation with the root lodging resistance. The indirect effect of ear height and root cap diameter on the root lodging resistance was equally significant. Therefore, these traits should be closely monitored in breeding to improve maize's lodging resistance.