Analysis on combining ability between temperate high-oil maize inbred lines and tropical maize germplasms.

Six local temperate high-oil maize inbred lines were corssed with four tropical maize inbred lines which combined 45 testcrosses.These testcrosses were field-tested for agronomic trait performances and estimation of genetic parameters under two environment including Kunming and Dehong of Yunnan province based on Griffing Ⅳ design.The results showed that the tropical maize inbred lines YML146,CML166,CML161,and CML171 with high combining ability for various agronomic traits were very useful germplasms for broadening genetic base of temperate high-oil maize and thus could be directly used in high-oil maize production and breeding programs.The positive effects of specific combining abilty(SCA) for grain yield were mainly presented in the crosses temperate high-oil maize inbred line × tropical maize inbred line or tropical maize inbred line × temperate high-oil maize inbred line.It indicated that there were significant genetic differentiation between temperate high-oil maize germplasms and tropical maize germplasms.Therefore,using temperate high-oil maize inbred lines to cross with tropical maize inbred lines was a very important way in developing elite high-oil maize hybrids.Due to the variance of additive effect for main agronomic traits was higher than that of non-additive effect,it could be concluded from this study that most of genetic effects for major agronomic traits were additive and thus these agronomic traits studied were recommended to be selected in earlier generations.