玉米甜糯双隐自交系穗部性状配合力分析及鲜食育种价值评价

穗部性状对于鲜食玉米育种具有重要意义,尤其是秃尖长度和籽粒大小。本研究采用不完全双列杂交NCⅡ设计,对5个甜糯双隐自交系17HN79、17HN84、17HN88、17HN97、17HN98的穗行数、穗行粒数、穗长、穗粗、秃尖长度及籽粒大小等6个穗部性状的一般配合力(GCA)和特殊配合力(SCA)及遗传率参数进行分析。结果表明:6个穗部性状的广义遗传率在65.5%~97.0%之间,狭义遗传率在29.3%~64.0%之间,穗长和籽粒大小主要由非加性基因作用为主,而穗粗、穗行数、穗行粒数和秃尖长度受加性基因作用为主。甜糯双隐自交系17HN98在穗长、穗行粒数、籽粒大小和减少秃尖长度方面表现较高的一般配合力相对效应,是具有较好鲜食玉米育种应用价值的甜糯双隐自交系。结合一般配合力、特殊配合力及穗部性状综合表现,筛选出17HN98/100、17HN98/107和17HN98/109三个表现突出的鲜食玉米杂交组合。

Combining ability analysis of ear traits and breeding value evaluation of sweet-waxy inbred maize lines of double recessive genotype

Ear traits,especially the length of bald tip and grain size,are important for fresh-eating maize breeding.In this study,we analyzed the general combining ability(GCA)and special combining ability(SCA)and heritability parameters of six ear traits of five sweet-waxy double recessive inbred lines including 17HN79,17HN84,17HN88,17HN97 and 17HN98 by using incomplete diallel crossing design.The results showed that the general heritability of six ear traits ranged from 65.5%to 97.0%and narrow heritability ranged from 29.3%to 64.0%.The ear length and grain size were mainly determined by non-additive genes,while the ear diameter,row number,grain number per row and bald tip length were mainly influenced by additive genes.The relative effects of GCA in sweet-waxy maize inbred line double recessive genotype 17HN98 was with higher in terms of ear length,grain number per row,grain size and bald tip length reduction,and was a sweet-waxy double recessive inbred line with better breeding value.17HN98/100,17HN98/107 and 17HN98/109 were the outstanding fresh-eating maize hybrid combinations based on GCA,SCA and ear traits performance.