糯玉米雄穗主要性状的配合力及遗传参数分析

Analysis of Combining Ability and Genetic Parameters of Main Characters of Waxy Maize Tassel

本研究选用11个表型差异较大的糯玉米自交系,通过不完全双列杂交(NCII)设计方法,对糯玉米雄穗分枝数、雄穗夹角和雄穗长分别进行配合力和遗传参数的分析,结果表明:(1)雄穗分枝数、雄穗夹角和雄穗长的一般配合力(GCA)正效应值前3名的自交系分别为N14-1>N9-1>N11-2、N27-1>N11-2>N8和N9-1>N1>N11-2;(2)3个性状受非加性基因和加性基因共同调控,其中雄穗分枝数和雄穗夹角主要受非加性效应影响,雄穗长主要受加性效应影响;(3)11个自交系3个性状的GCA与其所组配的组合的特殊配合力(SCA)效应之间没有直接的相关性;(4)3个性状的广义遗传率分别为97.51%、92.79%和95.44%,表明3个性状的遗传变异主要由遗传决定,受环境影响较小。狭义遗传率较低分别为31.10%、53.27%和45.21%,雄穗分枝数和雄穗长均小于50%,在育种实践中,应逐步积累加性效应,于高世代进行选择;雄穗夹角大于50%,宜在低世代进行选择。

In this study,11 waxy maize inbred lines with large phenotypic differences were selected to analyze the combining ability and genetic parameters of the branching number of tassels,the angle between tassels and the length of tassels by incomplete diallel cross(NCII)design method.The results showed that:(1)The top 3 inbred lines with positive effect values of the number of task-branches,task-angle and task-length were N14-1>N9-1>N11-2,N27-1>N11-2>N8 and N9-1>N1>N11-2,respectively.(2)The three traits were regulated by non-additive genes and additive genes.The number of tassel branches and tassel angle were mainly affected by the non-additive effect,while tassel length was mainly affected by the additive effect.(3)There was no direct correlation between the GCA of the three characters of the 11 inbred lines and the special combining ability(SCA)effect of the combination.(4)The generalized heritability of the three characters were 97.51%,92.79%and 95.44%,respectively,which indicated that the genetic variation of the three characters was mainly determined by heredity and was less affected by environment.The narrow heritability was 31.10%,53.27%and 45.21%,respectively.The number of tassel branches and tassel length were less than 50%.In the breeding practice,the additive effect should be accumulated gradually,and selection should be made in the high generation.The angle of tassel is greater than 50%,and it is advisable to select tassel in the lower generation.