Study On The Analysis Of Slection And Applicaton Of New Corn Inbreds

Eight maize inbred lines selected by Academy of Agricultural Sciences of Maize inLiaoyuan city were crossed into28single crosses with Griffing．The general combiningability(GCA)，special combining ability(SCA)and genetic variability of six agronomiccharacters，including ear length，ear weight, barren tip length，rows per ear，kernels perear and kernels weight were analyzed．The results showed that:1. Among the8inbred lines we selected, Inbred line2711,2713and2716playedmuch better than others at ear length，ear weight, rows per ear，kernels per ear and kernelsweight. They are potential to breed high-yielding varieties. But Inbred line2716has a higher GCA ofthe barren tip length. Inbred line2715played worse than other seven inbred lines. It indicated that it canhardly breed high-yielding varieties. The other four inbred lines has no special characteristics.2. Ear length and rows per ear were mainly controlled by additive genetic effect; earweight, rows per ear, barren tip length and kernels weight were controlled by non-additivegenetic effect. As it showed that one had a high general combining ability, but the specialcombining ability may be low. The GCA and SCA were not necessarily linked. Therefore, inselecting the combinations, we should not only pay attention to the general combiningability, but also pay attention to the special combining ability.3. The special combining ability of28combinations tested showed significantdifferences in yield. The SCA of the Combination2709×2716,2713×2714,2713×2715arehigher in ear length, ear weight, rows per ear, kernels per ear and kernels weight. They hada high yield. It indicated that the inbred lines combining ability had significant effects onthe yield of the hybrids.4. Additive variances of ear length, rows per ear and kernels per ear were larger thanthe dominance variances. It suggested that these characters were mainly controlled byadditive genetic effect. It can be selected in the early generation. Conversely it can beselected later.5. We didn’t find a inbred line which had significant GCAs in six characters weanalyzed in this test. It indicated that a perfect inbred line would not exist. We can get agood combination according to the goal of breeding.