MOLECULAR EVALUATION AND BREEDING RESEARCH OF SOYBEAN GERMPLASM

本研究的目的是评估亚洲野生大豆和栽培大豆叶绿体和核基因组简单重复序列（SSR）位点的遗传变异。共分析了130个品种在41个核SSR位点的基因型，从每个20个连锁群。基因型谱的多变量分析揭示了亚洲的两个主要种质库，分别对应于日本和中国人群。叶绿体SSR分析揭示了栽培大豆中8个不同的母系谱系，每一个似乎都来自不同的野生大豆植株。此外，还从亚洲和欧洲各国引进了大豆地方品种和栽培品种。利用9个信息丰富的核SSR位点对泰国北方栽培大豆的遗传变异进行了分析。所获得的结果显示，不仅在收集的加入，但收集的加入和释放的品种之间的基因型谱的相似性，这表明在泰国北方，地方品种已经被释放的品种所取代。对黄脐大豆品种的耐冷性进行了初步研究。同时，还对灰毛品种的类黄酮3'羟化酶基因序列进行了分子多态性分析，发现了新的变异。

The purpose of this study was to evaluate the genetic variation at simple sequence repeat (SSR) loci of chloroplast and nuclear genomes for wild and cultivated soybeans collected in Asia. A total of 130 cultivars were analyzed for genotypes at 41 nuclear SSR loci that were selected from each of 20 linkage groups. Multivariate analyses for genotypic profiles revealed two major germplasm pools in Asia, which corresponded to the Japanese and Chinese populations. Chloroplast SSR analysis revealed eight different maternal lineages in cultivated soybean, which each appeared to have been derived from different wild soybean plants. In addition, soybean landraces and cultivars were introduced from various Asian and European countries. Genetic variation in the cultivated soybeans collected in the northern Thailand was evaluated with nine informative nuclear SSR loci. The results obtained revealed the similarity of genotypic profiles not only among the collected accessions, but between the collected accessions and the released cultivars, suggesting that in the northern Thailand, landraces had been already replaced by released cultivars. A preliminary study was also carried out to survey the chilling tolerance for soybean cultivars with yellow hilum. Molecular polymorphism in the sequence of a flavonoid 3' hydroxylase gene was also surveyed for cultivars with gray pubescence, and new variants were detected.