甜糯玉米自交系配合力分析及育种应用OA

[Objective]To improve the breeding efficiency of sweet-waxy maize by accurately evaluating parental combining ability and efficiently utilizing heterosis.[Method]Five waxy maize inbred lines were used as female parents,and five double-recessive sweet-waxy inbred lines were used as male parents.Twenty-five hybrid combinations were constructed using the NC Ⅱ mating design.The general combining ability(GCA)and specific combining ability(SCA)of agronomic traits were systematically analyzed,and excellent parents and hybrid combinations were screened based on heritability analysis.[Result]The inbred lines HNM05(GCA for plant height=26.45),and YN170(GCA for ear row number=0.96)exhibited significant positive GCA effects for key traits and could be utilized as core parents.Hybrid combinations HNM05/YN170(SCA for plant height=18.56)and 15YN02-1/YN169(SCA for ear weight=28.83)demonstrated significant heterosis,indicating high yield potential.Heritability analysis revealed that traits such as ear length(h2N=66％)and plant height(h2N=59％)had high genetic stability,making them suitable for early-generation selection.In contrast,traits such as single ear weight(h2N=19％)and kernel number per row(h2N=25％)were significantly influenced by environmental factors,requiring advanced-generation screening.The hybrid combination HNM05/YN167,screened in this study and named'Gantiannuo No.3',has been approved at the provincial level.This validates the practical value of combining ability analysis.[Conclusion]Combining ability and heritability varied significantly among different traits of sweet-waxy maize.Parental screening should consider both GCA and SCA.Traits with high heritability,such as ear length and plant height,are suitable for early-generation selection,while traits with low heritability,such as single ear weight and kernel number per row,require advanced-generation selection.