基于SRAP分子标记的材用云南松种质保存库构建策略

以云南松（Pinus yunnanensis Franch.）全分布区内干形优良的780株样株作为原种质，基于SRAP分析的位点作为种质保存库构建数据，设10%、20%、30%、40% 4个抽样比例，采用改进的最小距离逐步取样法构建其种质子集。结果显示：种质子集的多态位点保留率均在90%以上且等位基因保留率皆大于95%，5个遗传多样性评价参数最小值均为10%抽样比例种质子集，且该子集居群内的遗传多样性小于原种质；在种质子集与原种质的均值t检验中，10%抽样比例种质子集有2个指标与原种质间存在显著差异；方差F检验中，20%和10%抽样比例种质子集的分别有1个和6个遗传多样性指标与原种质有显著差异且方差小于原种质；种质子集的遗传多样性均值与原种质的相关系数全部达到0.99以上，40%和30%抽样比例种质子集的遗传多样性方差与原种质的相关系数均大于0.80；30%抽样比例种质保存库的平均遗传距离较原种质提高了52.16%，保持了原种质的方差分量分配模式，以较大的遗传距离实现了与原种质相似的聚类。本研究确认30%抽样比例种质保存库可以作为材用云南松种质资源的代表性子集。

Strategy for constructing Pinus yunnanensis germplasm bank for timber based on the SRAP molecular marker

The genetic loci of the SRAP molecular marker in 780 Pinus yunnanensis Franch samples from the whole distribution area were used to establish a high-quality P. yunnanensis timber germplasm bank. Four P. yunnanensis germplasm subsets were constructed by improved least distance stepwise sampling at four sampling proportions, i.e., 10%, 20%, 30%, and 40%. Results showed that polymorphic locus retention rate of the four germplasm subsets was above 90% and the allele retention rate was greater than 95%. The minimum values of the five genetic diversity parameters were obtained from the germplasm subset constructed using the 10% sampling proportion, and the genetic diversity in the population of this subset was smaller than that of the original germplasm. Mean t-tests between the original and germplasm subsets showed significant differences between the 10% sampling ratio germplasm subset and the original. Furthermore, for the variance t-tests, several indicators of genetic diversity demonstrated significant differences between the original germplasm and the 10% and 20% germplasm subsets, respectively, and the variances of these germplasm subsets were smaller than those of the original. The correlation coefficients of the mean genetic diversity between the original germplasm and the four germplasm subsets all reached 0.99. The correlation coefficients of genetic diversity between the original and the 40% and 30% germplasm subsets were more than 0.80. The average genetic distance of the 30% germplasm subset was 52.16% higher than that of the original germplasm; at the same time, the distribution pattern of variance components of the original germplasm was well maintained and similar clustering to the original germplasm was achieved with a large genetic distance. Therefore, the 30% sampling proportion germplasm subset could be used as a representative subset of the germplasm resources of P. yunnanensis.