Studies on populotion dynamics of a perennial herb through DNA analysis and a matrix model

应用PCR方法对克隆植物小播苔草的地方居群进行了遗传结构分析。该物种原产于日本沙丘，通过根茎克隆繁殖。每株无性系的寿命为1年，平均每株无性系产生1.2个子株。在Ajigaura海岸沙丘系统中获得了一个新梢种群的统计数据。在此基础上，建立了转移矩阵模型来研究种群的生存和生长。真实的种群的大小分布与稳态下的大小分布相似，这是模型的预期结果。这意味着种群处于接近稳定的状态。该模型预测，根据当地环境的变化，种群规模将以每年0.9-1.4只的速度增长。从种子培育的个体植物中提取总DNA。这些种子是从日本各地收集的。用PCR方法研究了群体间和群体内的DNA变异。结果表明，日本地方群体间的遗传变异非常有限。也提出了群体内遗传分化的可能性。

The PCR method was applied to identify genetic structure of a local population of a clonal plants, Carex kobomugi. The species is native to Japanese sand dunes and reproduce clonally by rhizomes. The longevity of each ramete is 1 year and each ramete produced on average 1.2 daughter rametes. Demographic data of a shoot (ramete) population was obtained in the field in Ajigaura coastal dune system. Based on the date, a transition matrix model was developed to investigate survival and growth of the ramete population. The size distribution of the real population was similar to that at a steady state, which was expected from the model. This implies that the population was under a near-stable condition. The model predicted that the size of the population will increase at a rate of 0.9-1.4/year depending on the variation in the local environments. Total DNA was extracted from individual plant raised from a seed. The seeds were collected from various localities in Japan. The DNA variations between and within populations were investigated by the PCR methods. The results showed that the genetic variation between local populations in Japan was very limited. A possibility of within-population genetic differentiation was also suggested.