Combining Ability of Traits Related to Nitrogen Use Efficiency in Eighteen Maize Inbred Lines

Abstract

Traits related to maize yield and nitrogen use efficiency were analyzed in 108 hybrids(18 female inbred lines and six male standard testers). Nitrogen efficiency related traits in maize inbred lines were statistically analyzed in NC-II design experiments, and yield and nitrogen use efficiency characteristics of the hybridized combination were evaluated in combining ability analysis. The results showed that relative chlorophyll content, which was significantly correlated to nitrogen use efficiency at silking stage in two treatments, could be used to evaluate maize inbred lines. Nitrogen use efficiency played the main role in control treatment; however absorption efficiency was more important when nitrogen was applied. Combining ability analysis indicated that at least one inbred with higher general combining ability(GCA) were necessary to make a combination with high specific combining ability(SCA) in nitrogen use efficiency breeding. Total combining ability(TCA) of the parents determined the yield and nitrogen use efficiency in F1, certifying TCA could be used in nitrogen efficiency breeding. Inbred lines, BL12 in N225 treatment and BL48 in N450 treatment, presented higher GCA, performing as potential good breeding materials; BL12 × 178 in N225 treatment and BL48×Ye 478 in N450 treatment were combinations with outstanding nitrogen efficiency.