Effects Of Mountain And Valley On The Genetic Structure Of Eupatorium Adenophorum Populations

Eupatorium adenophorum (crofton weed) is one of the most widespread invasive species in the world. Its genetic diversity and population structure may be effected by the natural landscape. In order to understand mountain and valley landscape influence on genetic diversity and genetic structure of E. adenophorum populations, we selected four primer pairs of amplified fragment length polymorphism (AFLP) to study 30 populations sampled from southern part of Gaoligong Mountain and its both sides valley in Yunnan Province. The AFLP bands were interpreted as dominant markers and were scored for the presence or absence of bands (1= present,0= absent). The genetic parameters were analyzed using POPGENE, GenAlex, and NTSYS. The results were summarized as follows.81 amplified bands were produced by four AFLP markers from 652 samples, and 60 bands were polymorphism. Percentage of polymorphic bands (PPB) was 74.07%. Shannon index was 0.2313, and Nei’s (1973) gene diversity was 0.1405.We compared populations on eastern and western side of the Gaoligongshan Mountain and populations along three routes across the Mountain by genetic variation coefficient (Gst), gene flow (Nm), and Analysis of Molecular Variation (AMOVA). Genetic diversity of crofton weed populations had no significant difference between the both sides of the Mountain. The mountain blocked the population expansion at some degree, moreover, human disturbance should be considered also. Valleys took a role as corridor for the population distribution, but the population differentiation and gene flow were dissimilar in Longchuanjiang valley and Nujiang valley. Local adaptation and disturbance might put effects on the croften weed invasive procedure.