Breeding Potential Analysis Of 19 New Election Maize Inbred Lines

In this study,19 maize inbred lines selected newly by Maize Research Institute of Sichuan Agricultural University testcrosses with 7 often used inbred lines as females in southwest China according to NCⅡdesign. The combing ability and heterosis of main traits of 19 inbred lines were estimated. The heterosis groups and heterosis pattern of 30 inbred lines, including 19 inbred lines,7 testers and 4 temperate inbred lines (Huangzaosi,Mol7,Dan340 and Ye478),were studied with SSR markers. The main results were as follows:1. Genetic variance was significant in the 19 observed traits in 133 hybrid combinations apart from the rows per ear. The combing ability analyses indicated that the GCA and SCA of traits were marked (p<0.05or0.01) except for the GCA and SCA for the kernel depth and the SCA for the Axis weight. The inbred line H5054 showed the highest GCA for yield, followed by the inbred line H5049, and the GCA for yield component traits of the anther lines was high. The GCA of tester R08 and ES40 show highly positive effective. They have better utilization value to combing with the tested lines.2. The results of 133 crosses SCA showed that the combination RP125×H0016 indicated the maximum SCA positive effective for Ear length, Kernels per row and Plant weigh, and negative effective for Sterile length. The combination 18-599×H0016 showed the max SCA negative effective for Sterile length and SCA positive effective for Ear length, Ear weight and Plant weigh. the combination RP125×H0016 showed the better SCA effective. the combination 18-599×H0016 indicated the poor SCA effective. Combined with the Analysis of GCA, This results indicated that the heterosis of the hybrids combination were determined by the GCA of each parents along with the SCA between them, Both GCA and SCA should be considered when the inbred lines is selected.3. The coefficient of genetic similarity of 19 newly selected lines range from 0.47 to 0.80, with an average of was 0.616. The coefficient of genetic similarity of 30 inbred lines range from 0.15 to 0.74, with an average of 0.611.30 inbred lines derived from 5 synthesized maize populations when the coefficient of genetic similarity was 0.632, the result considered there were the Larger genetic differences and some genetic diversity among the 19 maize inbred lines.4. The combing pattern of 24 the hybrid combinations that 10% more than CK were analyses, the result showed that they were combined with lines belonged to different groups. The Heterosis pattern of the 14 corn hybrid combinations was the temperate germplasm cross with lines belonged to the tropical germplasm. The proportion was 58.30%. Therefore, this superiority pattern may valuable to be developed in the future t maize breeding.