Analysis On Mutation Type Of See2b Gene In Elite Inbred Lines Of Maize

Maize is one of the three good crops. Output and planting area of maize has surpassed those of wheat in recent years, making maize become important food, feed and sources of chemical raw materials. Ever since a long time ago, elite inbred lines played a key role in maize new species cultivation. However, much time is needed to breed of elite inbred lines, it is significant for accelerating breeding of maize, cutting time of breeding and studying on formation mechanism of maize elite inbred lines to create detection for maize elite inbred lines. Leaf senescence and nitrogen transport in maize are controlled by See2 gene coding cysteine protease. Nitrogen transport is enhanced along with leaf senescence controlled by homologous See2b gene, It is considered that See2b gene played a key role in nitrogen utilization in the process of leaf senescence in maize.In my study, Maize inbred lines 18-599, 08-641, 21-ES from Sichuan Agricultural University, Dan 340 from Lu DHG groups, ye478 from Reid groups, Mo17 from Lancaster group with its derivative lines, huangzaosi from Tang SPT group with its derivative lines were, totally 52, collected as experimental materials. All the materials are conducted to divide Heterotic groups through molecular methods as well as studies of Agronomic traits. And results are summarised as follows:1. It is found that Mo17 with its derivative lines have rich SNPs,Nan23232 and nongda178 were divided into the same heterotic group because of same American blood, xi14 and 412 were divided into the same heterotic group because of another material xu053. There was little mutains in he344,which was the best sameness with See2b gene.2. It is found that indels of huangzaosi and its derivative lines were poorer than those of mo17 derivative lines by analyzing the sequences of See2b genes of the two derivative lines. Then we presume that Huang and its derivative lines were relatively stable genetic. It is found that huangzaosi derivative lines except kl2, 8723, qi401, wenqingl331, duo27 and⑦61 had a same 22bp deletion segment in the nineth exon with ye478, 21-ES and guan17. And this mutation type of see2b gene had not been reported. Therefor, we could presume that the 22bp deletion segment in the ninth exon may lead to changes of see2b gene functions of maize.3. Same mutation laws is showed between 18-599,21-ES, 08-641, ye478, jie1037, and jie842, which is indicated that 21-ES and 08-641 are close to the materials which have the American Blood, while 18-599 and dan340 are divided into one group. So it is concluded that 18-599, 08-641 and 21-ES is closer to Mo17, ye478 and dan340 in blood than to huangzaosi.4. Dividing with Agronomic traits, we found that 18-599,21-ES, 08-641, nan23232, nongdal78 and Mol7 were divided in No.1 group.Xil4 and 412 were were divided in No.2 group,which are the same as those divided by SNPs in See2b gene. In huangzaisi and its derivative lines, 18-599,21-ES, 08-641 and K12 were divided in the same group,huangyesi and baiyesi were divided in the No.3 group,then others were in the same group.