无瓣海桑引种种群遗传多样性的ISSR分析

GENETIC DIVERSITY OF INTRODUCED POPULATIONS OF SONNERATIA APETALA BASED ON INTER-SIMPLE SEQUENCE REPEAT ANALYSIS

采用ISSR(inter-simple sequence repeat)分子标记技术对采自海南和深圳的2个无瓣海桑Sonneratia apetala种群共45个个体进行了遗传变异分析。11个ISSR引物共扩增出196条带,其中128条具多态性,多态位点百分率为65.31%。在种群水平上多态位点百分率为48.47%。Nei的基因多样性、Shannon信息指数在物种水平上分别为0.155 6和0.244 1,在种群水平上分别为0.140 3和0.214 2。无瓣海桑从海南引种到深圳后,遗传多样性水平有所降低。依据Nei的基因分化系数和AMOVA(analysis of molecular variance)分析结果,无瓣海桑种群间发生了一定的遗传分化,但绝大多数遗传变异发生在种群内的个体间。种群间遗传一致度为0.964 5,遗传距离为0.036 2。UPGMA聚类分析表明,来自同一种群的个体一般都聚在一起。

Sonneratia apetala is a mangrove species, which belongs to Sonneratiaceae. Leaf samples of forty-five individuals from two S. apetala populations of Hainan Island and Shenzhen of China were collected. Eleven inter-simple sequence repeat primers gave rise to 196 discernible DNA fragments, of which 128 （65.31%） were polymorphic. The percentage of polymorphic bands at population level was 48.47% on average. The Nei＇s gene diversity and Shannon＇s information index were 0. 155 6 and 0. 244 1 respectively at species level,0.140 3 and 0. 2142 respectively at population level.Shenzhen population had a relatively lower genetic diversity than Hainan population. According to Nei＇s Gst value and analysis of molecular variance, some genetic divergence occurred between populations; however, most of the genetic variance resided in between individuals within populations. The genetic identity and genetic distance between the two populations were 0. 964 5 and 0. 036 2 respectively.Cluster analysis showed that individuals from the same population were usually grouped together.