Study on the Heterosis Potential of Maize Inbred Lines Possessed Tropical and Subtropical Germplasm

Four Maize inbred lines possessed tropical and subtropical germplasm were top-crossed with six Chinese elite inbred lines by Griffing NC Ⅳ mating system, and combing ability and utilization potential of four Maize inbred lines possessed tropical and subtropical germplasm were evaluated. The results showed that the average value of the general combing ability(GCA) that Maize inbred lines possessed tropical and subtropical germless(0.071)were higher than Temperate zone inbred lines(-0.047).Eight Tropical/Temperate zone crosses and a Temperate/Temperate zone cross possessed higher special combing ability(SCA) among forty-five top-crosses, but Tropical/Tropical's weren't significant.The SCA of Tropical/Temperate zone crosses(0.385) were higher than Tropical/Tropical(0.108) and Temperate/Temperate zone crosses's((-1.620).)The Maize inbred lines possessed tropical and subtropical germplasm and sufficient genetic diversity were top-crossed with temperate zone inbred lines, there were higher heterosis.