Efficiency Selection Of Genetic Background Using SSR Markers In Soybean

Soybean is an important economical crop and main resource of protein. Soybean seeds contain at least three lipoxygenase isozymes lipoxygenasel, 2 and 3. These isozymes are responsible for the production of unpleasant grassy and beany flavors in soybean seeds that have limited the development of soybean products for human consumption. Treatments with heat, acid, alcohol or antioxidants have been employed to reduce the concentration of compounds that contribute to the undesirable flavors. An alternative solution to this oxidation problem would be to genetically eliminate lipoxygenase from seeds.Developing seed lipoxygenase-free soybean cultivars with desirable agronomic and seed characteristics is the best solution. Aim of this study is using markers to reduce the number of backcrossing generations to obtain desirable lines for further backcross based on the lines with lacking of lipoxygenase. The targeted gene is detected by IEF-PAGE; using SSR markers to accelerate the recovery of the recurrent parent genome, to select the ideal lines, which not only have the desirable gene, but also have little difference with the genetic background of an elite variety called ludou 4.The main results are as follows:51 parrs of SSR primers used in the research have specific alleles of ludou 4. On the soybean molecular linkage group, only H and L linkage groups have one SSR locus, the other 18 linkage groups have at least two SSR loci and the loci were evenly distributed.A procedure was useful in marker-assisted background selection. That is, first use limited numbers of markers to screen all the individuals, eliminate the individuals not fit the requirements, then use more makers to screen the residuals. With this method, ideal individuals can be obtained with high efficiency.A line lacking Lox-2 was got, which can be seen as a near-isogenic line of loudou 4 based on the background selection results. Candidate lines were chosen for further backcross with ludou 4, to accelerate the process of getting near-isogenic lines of loudou 4 lacking different types of lipoxygenase.