莲瓣兰DALP遗传多样性研究

采用DALP(Direct amplification of length polymorphism)检测莲瓣兰5个居群的遗传结构.5个引物组合共检测到103个多态位点.和其它具有相似生活史(多年生草本、以动物为媒介的杂交、种子随风散布)的物种相比,莲瓣兰原变种水平(PPB=88.18％,A=1.8818,Ae=1.4880,H=0.2911,I=0.4412)和物种水平(PPB=93.64％,A=1.9364,Ae=1.5262,H=0.3129,I=0.4732)均具有较高的遗传多样性；各居群间(Gst=0.3292)存在较大的遗传分化.基因流的估计值(Nm=1.0186)表明莲瓣兰物种水平上各居群间每代有1.0186个移居个体.地理隔离和选择压力可能是造成莲瓣兰居群间基因流动受到限制的原因.在这些研究的基础上,探讨了野生莲瓣兰资源的保护问题.

Genetic diversity of Cymbidium tortisepalum by DALP

DALP was applied to evaluate genetic variation and structure of 5 populations of Cymbidium tortisepalum.The results were as follows:103 DALP polymorphic loci were detected in four populations using 5 random primers.Compared with other long lived herbaceous perennials,animal pollinated outcrossing species and wind dispersal seeds,the total genetic diversity of C.tortisepalum was relatively high both at the subspecies(PPB=88.18%,A=1.8818,Ae=1.4880,H=0.2911,I=0.4412) and species levels(PPB=93.64%,A=1.9364,Ae=1.5262,H=0.3129,I=0.4732);and there was much genetic differentiation among population(Gst=0.3292).An indirect estimate of the number of migrants per generation(Nm=1.0186) suggested about 1.0186 migrants in every generation.The isolation from parent population and the selective pressure might be the causes leading to the restriction of gene flow.Based on these results,the conservation strategies of this species were developed.