Studies On The Combining Ability And Genetic Model Of Main Characters For 21 Maize Inbred Lines

In this paper, 98 crosses were made by NCII design with 21 inbred lines ( consisting of 7 P1(□) and 14 P2 (□)). The 21 parents and 98 crosses were evaluated for grain yields and the other 18 agronomic characters. Analysis of variance, analysis of combining ability, correlation analysis and genetic model test were made on these characters. The main results were as followed:1. GCA and SCA variance of plant height, ear height, stem diameter, tassel main axis length, tassel branch number, leaf area, leaf shape coefficient, leaf angle, leaf orientation value, bald top length of ear, ear length, ear diameter, ear row, number of kernels per row,axis diameter, 100-grain weight, grain weight per ear, ratio of kernel dry weight per ear and grain yield was significant at 0.01 level.Inbred line 7327, 5151, 5311, Mu6, Mu4, Zhen367, Jiao51, 180 had higher grain yield, and Jiao51, 7327, 7331, 180 had higher GCA of grain yield. The grain yield of any cross between female parents and Jiao51, 7331, 180, 7327 was higher. The crosses of higher grain yield in 98 crosses were Dan 340×Jiao51, Dan340×095, 330×Jiao51, Zheng22×7331, Zheng22xJiao51, Dan340×180, Dan340×7327, Dan340×7331, Zheng22×7327 and Huangzaosi×7331. Therefore, Jiao51, 7331, 7321, 180 were better inbred lines and high plant yield crosses could probably be screened from crosses conbined by these inbred lines. Other inbred lines had their own advantages and could be used in different breeding aims.According to plant yield, plant-type and ear and kernel characters of hybrids, the crosses of Dan340×Jiao51,330×Jiao51 and Dan340×l80 were better.2. The higher broad and narrow heritability of the tassel branch number, leaf area, leaf shape coefficient, leaf orientation value, ear length, ear diameter, ear row, number of kernels per row, axis diameter, 100-grain weight, grain weight per ear, ratio of kernel dry weight per ear indicated that these characters were less influenced by environment. But the lower heritability of tassel main axis length, leaf angle, bald top length of ear indicated that these characters were more influenced by...