Cloning Of BT2, RbcS And Heterosis Analysis Of Heterozygous Loci In Corn

In this study, the hybrids field characters of 9 inbred lines of corn were analysised, and the sequence of genes BT2 and RbcS was cloned. The expression of heterozygous has been analysised by RT-PCR for looking for heterozygous loci which lead to high expression. For the mechanism of heterosis and utilization basis. The main results are followed:1. The variances of 5 traits of 35 hybrid combinations were analysed. The results showed that the variances among combinations were very significant. The result shows that only one average of ear weight heterosis traits in more than 50%, ear length and ear weight are positive heterosis, and kernels per ear, 100-kernel weight were part of the negative heterosis. The heritability of the traits was analysed, the sequence of the heritability in narrow sense was kernel weight of ear >ear weight> row number per ear>100-kernel weight > row number per ear. The variances analysis showed that inbred lines LX9801,137å'ŒZheng58 had higher general combning ability effect values in ear length, zheng58,Chang7-2,87-1å'ŒLX9801 had higher general combning ability effect values in yield.2. In the nine maize inbred lines, there are four effective mutations sites in BT2 gene ,respectively, 9, 235, 324 and 376 sites. RbcS gene have five effective mutations 48, 142, 353, 412 and 601 sites. There is no significant difference in the basic characteristics and structure of BT2 gene and RbcS gene corresponding of the protein.3. The relative expression has been analysised in the heterozygous and homozygous state of BT2 gene and RbcS genes, the results shows that BT2 effective mutation in 235 points and 324 point lead to BT2 relative expression was reduced; 376 point has increased expression of BT2 gene. There are five mutations in RbcS gene, 48 point and 353 point change caused a reduction of RbcS gene expression, 142 point and 601 point of the changes led to the rise of RbcS gene expression.4. The heterozygosity of 376 point in BT2 gene was predicted to be increase row number per ear, 100-kernel weight, ear weight. The heterozygosity of 142 point in RbcS gene was predicted to be increase row number per ear, 100-kernel weight, ear weight.