Abstract:

The primary objective of this study was to estimate combining ability and its genetic parameters of a set of 17 newly inbred lines. The materials included 11 testers, which used commonly in southwest regions, 17 newly inbred lines obtained from landraces maize germplasms, and 187 (11×17) combinations which were crossed with 17 new maize inbred lines and the 11 testers by NC II mating design. The combining ability of 17 inbred lines was analyzed based on the date for the experiment. The genetic parameters and heterotic group were done basing on combining ability. The results showed that P1-1, P1-16 and P1-14 with the better comprehensive characters can be directly used in maize breeding program. The SCA of P1-10×P2-4 was high in most traits, it brought out strong heterosis. It is more possible to obtain high field hybrid combinations by the pattern Sipingtou × Lancaster. GCA variance was bigger than SCA variance in rows per ear, kernels per row etc four characters, they were affected by the environments slightly and should be selected at early generations, yet SCA variance of 100-kernel weight and plant weight etc five characters was bigger than GCA variance, they were accessible to the environment, so they were not to be selected in early generations.