利用RAPD技术分析了长叶榧(Torreya jackii Chun)的遗传结构,用18个引物对来自福建省泰宁县的3个不同居群的66个长叶榧样本进行分析。结果显示,长叶榧群体水平的多态位点百分率达87%,居群水平的多态位点百分率分别为83%、68%和80%。群体水平上的Nei基因多样性指数为0 2479,居群水平上分别为0 2182、0 1684和0 1881。群体水平上的平均杂合度达到0 2447,居群水平上分别为0 2215、0 1729和0 1950。30 35%的遗传变异存在于居群间,69 65%的遗传变异存在于居群内。长叶榧居群的基因流量为1.6899,显示长叶榧仍具有通过群体间的基因交流来防止遗传漂变造成的群体分化的能力。

The genetic diversity of Torreya jackii Chunwas researched by RAPD.18 primers were screened to amplify the genome of 66 samples of T. jackii from 3 populations in Taining County of Fujian Province. These primers detected 199 reproducible fragments among which there were 173 reproducible polymorphism fragments. The results showed that the percentage of polymorphic site atspecies levelwas87%,and they were 83%, 68% and 80% at population levels respectively. Nei' s gene diversity index was 0.247 9 at species level, and 0.218 2,0.168 4 and 0.188 1 atpopulation levels respectively. The heterozygositywas0.244 7 at species level, and 0.221 5,0.172 9 and 0.195 0 respectively at population levels. The percentage of genetic variance was 30.35% among T. jackii populations, and 69.65% within population. The gene flow index of the species was 1.689 9, it was suggested that the species still has the ability to recover from its endangered situation through promoting the genetic communication among populations.