Han B, Zhao M
College of Life Sciences, Inner Mongolia Agricultural University, Hohhot 010018, Inner Mongolia, China.
Genetika. 2011 Sep;47(9):1223-9.
The soil seed bank represents the potential plant population since it is the source for population replacement. The genetic structure of a Stipa krylovii (Roshev.) plant population and its soil seed bank was investigated in the Xilinguole Steppe of Inner Mongolia using random amplified polymorphic DNA (RAPD) analyses. The population was sampled at two sites that were in close proximity to each other (0.5 km apart). Thirty plants and 18 seed bank samples were taken from each site to determine the genetic diversity between sites and between sources (plant or seed). The material was analyzed using 13 primers to produce 92 loci. Eighty-six were multi-loci, of which 23 loci (26.74%) of allele frequencies showed significant differences (P < or = 0.05). The genetic similarity between two seed bank sites was 0.9843 while the genetic similarity between two plant sites was 0.9619. Their similarities were all greater than that between the seed bank and plant populations. An analysis of their genetic structure showed that 87.86% of total variation was derived by two-loci. Genetic structures between plant and soil seed bank populations in S. krylovii were different due to the variance of mean gametic disequilibria and mean gene diversity. AMOVA results showed that the majority of variance (88.62%) occurred within sites, 12.75% was from between-groups. Further research is needed to investigate the selective function in maintaining the genetic diversity of Stipa krylovii plant populations.
土壤种子库代表着潜在的植物种群，因为它是种群更替的来源。利用随机扩增多态性DNA（RAPD）分析方法，对内蒙古锡林郭勒草原克氏针茅（Stipa krylovii (Roshev.)）植物种群及其土壤种子库的遗传结构进行了研究。在两个彼此相邻（相距0.5公里）的地点对该种群进行了采样。从每个地点采集了30株植物和18份种子库样本，以确定不同地点之间以及不同来源（植物或种子）之间的遗传多样性。使用13条引物对材料进行分析，共产生92个位点。其中86个为多位点，等位基因频率中有23个位点（26.74%）显示出显著差异（P≤0.05）。两个种子库地点之间的遗传相似性为0.9843，而两个植物地点之间的遗传相似性为0.9619。它们的相似性均大于种子库与植物种群之间的相似性。对其遗传结构的分析表明，总变异的87.86%来自两位点。由于平均配子不平衡和平均基因多样性的差异，克氏针茅植物种群与土壤种子库种群之间的遗传结构不同。方差分析（AMOVA）结果表明，大部分变异（88.62%）发生在地点内，12.75%来自组间。需要进一步研究来探讨维持克氏针茅植物种群遗传多样性中的选择作用。
