Association Mapping Of Quantitative Trait Loci Of Soybean Sprout-Related Traits

Soybean sprout is a special vegetable. When soybean seed was under the manual control of the appropriate temperature and water, and then formed sprout vegetable. It is a traditional vegetable and has a long history of production and consumption in China. Soybean sprout-related traits are most controlled in a complex manner by quantitative trait loci (QTLs). Mapping these traits not only to research the genetic law, also can contribute to marker assistant selection the baseline of gene clone. In this study, mini core collections of cultivated soybean in China were selected and a two-year field experiment was carried out. The genetic variations of fresh yield of soybean sprout, dry yield of soybean sprout, length of hypocotyl, length of root, percentage of normal seeding and100-seed weight were analyzed, and association mapping of the loci for fresh yield of soybean sprout, dry yield of soybean sprout, length of hypocotyl, length of root, percentage of normal seeding and100-seed weight were done by using138SSR markers. The main results as follows:1. There were greet variation of this population with fresh yield of soybean sprout, dry yield of soybean sprout, length of hypocotyl, length of root, percentage of normal seeding and100-seed weight. The population is suitable for association mapping. The correlation between fresh yield of soybean sprout and other5traits were highly significant. We screen14elite germplasms from the population; these resources can be improved directly or be used as breeding improved intermediate material.2. There were752alleles detected in243cultivated soybeans from the mini core collections of cultivated soybean in China, the average allele number (A) per locus was5.45, the average polymorphism information content (PIC) was0.569.3. Through the analysis of LD on20linkage groups for all materials in China, we found that regardless of linear combination, or non-linear combination, they both had a certain degree LD, but the combination number of D’>0.5was very small, which was only0.18%of total. Based on the results, we found D’of mini core collections of cultivated soybean in China was rapid decay with genetic distance. According to the Hardy-Weinberg equilibrium model, the mini core collections of cultivated soybean in China were divided into two subpopulations by STRUCTURE software. Association mapping analysis was conducted by using the GLM model with the modified population structure as covariant Under the significance level below0.05, twenty-eight markers linked to six soybean sprout-related traits.4. Under the significance level below0.01, eight makers linked to100-seed weight, two linked to fresh yield of soybean sprout, one marker linked to length of hypocotyl, and one marker linked to percentage of normal seeding. Six elite alleles for eight loci of100-seed weight, three elite alleles for two loci of fresh yield of soybean sprout, one elite allele for one loci of length of hypocotyl, one elite allele for one loci of percentage of normal seeding.