基于微卫星的喀斯特地区长梗吊石苣苔和吊石苣苔的遗传多样性研究

长梗吊石苣苔Lysionotus longipedunculatus (W.T. Wang) W.T. Wang是我国吊石苣苔属中的一个比较罕见的物种,目前濒危等级被评估为极危CR Blac (ⅰ,ⅱ,ⅴ),而同属的吊石苣苔L. pauciflorus Maxim.分布范围非常广泛、生境变化多样,濒危等级为无危LC。本研究通过筛选出16个微卫星位点对长梗吊石苣苔的两个居群进行遗传多样性研究,并对比相近地区的吊石苣苔居群,比较研究导致长梗吊石苣苔濒危的原因。结果显示二者的遗传多样性都比较低,有较高自交现象,但吊石苣苔具有明显的走茎,可以有效地克隆繁殖,相较之下,长梗吊石苣苔较弱的克隆繁殖能力可能是导致其濒危的原因之一。

Study on the Genetic Diversity of Lysionotus longipedunculatus and L. Pauciflorus in Karst Limestone Area based on Microsatellite Loci

Lysionotus longipedunculatus (W.T. Wang) W.T. Wang is a relatively rare species of Lysionotus in China. The current endangered grade is assessed as critically endangered CR Blac (i,ii,v). However,the congeneric plant L.pauciflorus Maxim. has a wide range of distribution,diverse habitats and the endangered grade is non-risk LC. In this study,16 microsatellite loci were screened to study the genetic diversity of two populations of L. longipedunculatus and L.pauciflorus,and the populations of the genus Lysionotus in the similar area were compared to study the endangerment cause of L.longipedunculatus. The results showed that the genetic diversity of these two species was low and they all had a higher proportion of inbreeding. However,L. pauciflorus had rhizome and could be effectively cloned and reproduced. In contrast,the weaker clone reproduction ability of L. longipedunculatus perhaps was one of the reasons leading to its endangerment.