The Genetic Differentiation Research On Wild Soybean Populations Of Dongying Region

Wild soybeans, the ancestors of the cultivated soybeans has formed manyabundant variation types in the long-term natural selection. It carries some advantagegenes such as the genes of diseases and pests, drought resistance, cold tolerance, salttolerance, barren resistance, high protein, and good podding. It’s also one of theimportant resources of soybean genetic breeding and also inaccessible soybeanbreeding materials on the research of soybean’s ecological, classification, origin,evolution, and physiology. However, the study of wild soybeans is still in a primarystage, part of it’s good genes has not yet been discovered, so the study of wildsoybean is important for wild soybean’s protection and utilization. Today, with thedevelopment of molecular biology techniques, some molecular markers has beenapplied to the genetic study of the wild soybean. This study selected wild soybeans inDongying, Binzhou region and adopted RAPD, ISSR and SSR as the molecularmarkers to detect the genetic diversity and the genetic variation, genetic structureamong and within the populations. And it also provides a molecular basis for the wildsoybean’s further protection and rational utilization.In this study, a high level of genetic diversities of wild soybeans was revealed bythree different indicators (P, H and I) whether using RAPD, ISSR or SSR analyses. InRAPD analysis the value of them are100.00%,0.4196,0.6057; In ISSR analysis thevalue of them are96.55%,0.3671,0.5429; and in SSR analysis the value of them are91.49%,0.3936,0.5659. The three methods got similar conclusions, and revealed thehigh level of six wild soybean populations’genetic diversities.Studies on the genetic variation and structure of different wild soybeanpopulations: the Gst value of RAPD analysis is0.3706, the Nm value is0.8492, theGst value of ISSR analysis is0.3317, the Nm value is1.0075, the Gst value of SSR analysis is0.2627, the Nm value is0.7017, all the results shows that a certain geneticdifferentiation had occurred among six populations and genetic variation mainlyexisted within populations, and the wild soybean gene exchange between thepopulations is not very frequently. UPGMA cluster analysis based on genetic distanceof three kinds of marking methods shows that5wild soybean populations ofDongying region was clustered together, finally clustered with wild soybeanpopulation of binzhou region, this is probably relates to its geographical position andliving environment.Using the Mantel test to describe the relationship between the three methods ofmolecular markers, the results indicated that three methods of molecular markers arecorrelatived. It’s reliable by using three methods to analysis the wild soybean’sgenetic diversity and genetic structure.