Brassica Napus Genetic Linkage Mapping And Qtl Analysis

Rapeseed is the third biggest source of vegetable oil, and one of most important oil crops in China.The main objective of research and breeding is to increase yield and oil content, as well as to improve the efficiency. Rapeseed yield components factor and oil content trait are typically quantitative trait controlled by multiple genes, vulnerability to environmental impacts. The formation and accumulation of rapeseed material is a complex physiological and biochemical processes. It is necessary for the use of modern molecular biological techniques combined with conventional breeding methods to study and analyze.In this study, the DH population (SG population)of 282 lines derived from a cross between the German cultivar Sollux and the Chinese cultivar Gaoyou, both having a high erucic acid and a very high oil content. Construction of the functional genetic map use EST markers, SRAP markers, miRNA markers etc. then QTL mapping were conducted for oil content and 1000-seed weight of phase harvested rapeseed.The main findings are as follows:1. Alignment functional genes sequence between Arabidopsis thaliana and Brassica napus,and reference literature, a total of 588 primer pairs designed to amplify fragments of different genes.which in 117 primer pairs amplified polymorphic bands in Sollux and Gaoyou,then detected on the SG group,increased 138 functional gene markers of the original map.2. Construction functional genetic linkage map use 123 SSR markers (original map data,changed), 30 SRAP markers, 7 miRNA markers, 52 EST markers, 49 markers LiEST. This map covered 1682.4cM with average marker interval of 7.5 cM.3. In this study,8 group datas in 5 traits showed a continuous distribution,and demonstrated bidirectional beyond parents。There are 6 group datas showed a normal distribution,In addition to 1000-seed weight and oil content which sampled in Zhejiang May 19.between different traits (except for oil content), there were significantly related to each other.4. Analysis datas of 1000-seed weight and oil content sampled twice in Zhejiang showed that rape is accumulation of material before Yellow mature,and 1000-seed weight will increased, It would be reduced when over-ripe; oil content reached stability at Green mature.between Different DTF, 1000-seed weight will reduce 0.1-0.15g when DTF delay three days, oil content unchanged.5. Application of composite interval mapping,55 QTLs(LOD≥2.5) were detected for 5 traits in Zhejiang and Shanxi,in which a single QTL heritability ranged from 0.21% to 19.45%.6. In this study,there are QTLs and non-QTLs interaction and between non-QTLs interaction was detected in epistatic interaction ,genotype and environment interaction. The later occupied the majority.The same locus may have interaction with different loci to affect the same trait, but the effect value differences.