Primary Research And Homologs Of GS3 And Ghd7 Genes In Brassica Napus

Rapeseed as one of the most important oil crops in the world,holds a pivotal position in China. However,shortage of rapeseed production is a prominent problem.Therefore increasing yield is still the focus of genetic improvement, while modern biological technology is an important tool to speed up the process of genetic improvement. At the present stage, rice,as a model crop is extensively researched in gene mapping and cloning of yield and related traits,and similar QTLs often exist in the vicinity of homologous sequences between rice and rape.The purpose of this study was that find a effective method to promote the rapeseed research by using concerned achievements in rice research,then two homologous genes were cloned in Brassica napus, which refer to the information of GS3 and Ghd7 that have important influence on the yield.57 varieties were investiage the yield and related traits, which were sequenced to find the molecular markers.Correlation between molecular markers and the yield were analyzed, predicted genes were maped in the TN DH groups and the relation that the predicted genes with the yield and the related traits were analyzed.The results of this study were as follows:1.According to the sequence information of rice genes GS3 and Ghd7 and relevant information in Arabidopsis,14 pairs of primers were designed, in which gs3-2,gs3-3, gs3-5,ghd7-2,ghd7-5,ghd7-6 and ghd7-7 were amplified successfully in Brassica napus S1300.Candidate genes Bngs-like and Bnghd-like were predicted by sequencing the spliced fragment and bioinformatics method. Through the structure prediction of candidate gene, important domain VWFC in GS3 were discovered in candidate gene Bngs-like, important domain CCT in Ghd7 were discovered in candidate gene Bnghd-like which has typical characteristics of CO gene family.2.Comparative sequencing in the 57 varieties.According to relevant information of Bngs-like and Bnghd-like,33 pairs of primers were designed for sequencing.One valid mutation site was found in the Bngs-like,the comparative sequencing primer of which is brgs-16.Two effective mutation sites were discovered in the Bnghd-like,the sequence primers of which are brghd-1 and ghd7-7.3.Correlation analysis between candidate genes Bngs-like and Bnghd-like and yield and yield related traits.Field experimental were designed using 57 brassica napus planted in Wuhan and Huanggang. Yield and yield components data were inspected as required.The correlation between brgs-16, brghd-1 and ghd7-7 and the survey data were analyzed respectively. No correlation between brgs-16 and yield and yield related traits were found, while ghd7-7 associate with plant height and flowering time.4.The candidate genes, Bngs-like and Bnghd-like,were located in the TN DH population.brgs-15 is SSCP marker located in A2 linkage group, ghd7-7 is a dominant marker located in A10 linkage group.The result of TNDH population QTL scan indicated there were many QTLs concerned with yield and yield related traits about ghd7-7,and there is no important QTLs with brgs-15.