大赖草种群遗传多样性的AFLP分析  

AFLP analysis on genetic diversity of Leymus racemosus in Xinjiang

作　　者：蔡小霞[1] 吾买尔夏提.塔汉 代培红[2] 加尔肯.切木森 

机构地区：[1]新疆农业大学草业与环境科学学院,乌鲁木齐830052 [2]新疆农业大学农学院,乌鲁木齐830052 [3]新疆哈巴河县草原站,836700

出　　处：《干旱区资源与环境》2017年第9期130-134,共5页Journal of Arid Land Resources and Environment

基　　金：国家自然科学基金项目(31160134)资助

摘　　要：采用荧光AFLP标记对大赖草(Leymus racemosus(Lam.)Tzvel)的6个天然种群进行了遗传多样性和遗传结构进行分析,6对选择性扩增引物共扩增出1269条清晰的条带,其中多态性位点1203个(PPL=80.61%)。在物种水平上,Nei’s遗传多样性指数H=0.188,Shannon多态性信息指数I=0.313;在种群水平上,H=0.177;I=0.288。遗传分化系数Fst为0.1009,表明有10.09%的遗传变异存在于种群之间,基因流Nm为4.4554>1,说明种群间基因交流可以阻止由于遗传漂变导致的遗传分化,遗传分化呈现均质化的趋势。PCo A聚类结果表明,大赖草种群间的遗传距离与地理距离有一定的相关性,但未达到显著水平。该研究结果显示,遗传多样性水平不仅与物种本身特性和研究方法有关,濒危植物并不一定表现为遗传变异水平的降低而濒危,还与人类活动与气候环境密切相关。The floresent amplified fragment length polymorphsim （AFLP） was used to evaluate the genetic diver- sity and genetic structure of six natural populationsof Leymus racemosus, which is an endangered species with a narrow distribution in Xinjiang, northwest of China. These selective amplification primers generated a total of 1, 269 unambiguous bands, of which polymorphic sites is 1,203 （80.61%）. At species level, Nei~ gene diversity （H） is 0. 188, and Shannon＇s information index （I） is 0. 313. At population level, H = 0. 177andI = 0. 288. Genetic coefficient of differentiation is 0. 1009, which shows 10.09% genetic variation exists among 6 popula- tions. The gene flow from Fst （Nm） is 4. 4554, which prevents genetic differentiation caused of genetic drift, and genetic differentiation presents homogenization trend. Clustering results showed that a certain correlation ex- ists between populations of L. racemosus genetic and geographic distances. Mantel test showed a positive correla- tion between geographic distance and genetic distance, but does not reach a significant level （ p 〉 0.05 ）. The study results showed that endangered plant may not be displayed by lower level of genetic variation, it is not only related to the species itself characteristics and research methods, but also on human activities and climatic envi- ronment.

关 键 词：大赖草 遗传多样性 遗传结构 荧光AFLP 

分 类 号：Q943[生物学—植物学]