基于遗传多样性和空间遗传结构的野生大豆居群采样策略

筛选了17对SSR引物对山东省垦利黄河口自然保护区野生大豆(G.sojaSieb.etZucc.)居群892份材料的遗传多样性及其随样本量变化而变化的规律进行了分析,同时以SSR的多态性为参照对该居群内的小尺度空间遗传结构进行了研究.发现该种群的平均每位点的等位基因数(A)为2.88,预期杂合度(He)为0.431,Shannon多样性指数(I)为0.699,多态位点比率(P)为100%.以计算机模拟方法随机抽取该居群不同个体组成的抽样样本,并计算各样本的多样性指数与样本量变化的回归关系,发现27~52个样本即可达到居群总体多样性水平的95%.通过空间自相关分析,得出该居群遗传结构的斑块大小约为18 m.该研究为野生大豆居群的合理取样提供了科学依据.

Sampling Strategy for Wild Soybean (Glycine soja) Populations Based on Their Genetic Diversity and Fine-scale Spatial Genetic Structure

A total of 892 individuals sampled from a wild soybean population in a natural reserve near to the Yellow River estuary located in Kenli of Shandong Province were investigated.Seventeen SSR primer pairs from cultivated soybean were used to estimate genetic diversity of the population and its variation pattern versus changes of sample size(sub-samples),in addition to investigating the fine-scale spatial genetic structure within the population.The results showed relatively high genetic diversity of the population with the mean value of allele number(A) being 2.88,expected heterozygosis(H_e)(0.431),Shannon diversity index(I) 0.699,and percentage of polymorphic loci(P) 100%.Different sizes of sub-samples(10 groups) were randomly drawn from the population and their genetic diversity was calculated by computer simulation.The regression model of the four diversity indexes with the change of sample sizes was computed.As a result,27-52 individuals can reach 95% of genetic variability of the total population.Spatial autocorrelation analysis revealed that the genetic patch size of this wild soybean population is about 18 m.The study provided a scientific basis for sampling strategy of wild soybean populations.