Genetic structure and demographic history of the endangered tree species D ysoxylum malabaricum ( M eliaceae) in W estern G hats, I ndia: implications for conservation in a biodiversity hotspot

作者：Sofia Bodare, Yoshiaki Tsuda, G. Ravikanth, R. Uma Shaanker, Martin Lascoux · 发表于：Ecology and Evolution · 年份：2013 · DOI：10.1002/ece3.669 · 被引用次数：29 · 研究领域：Genetic diversity and population structure、Plant and Fungal Species Descriptions、Phytochemical compounds biological activities

The impact of fragmentation by human activities on genetic diversity of forest trees is an important concern in forest conservation, especially in tropical forests. Dysoxylum malabaricum (white cedar) is an economically important tree species, endemic to the Western Ghats, India, one of the world's eight most important biodiversity hotspots. As D. malabaricum is under pressure of disturbance and fragmentation together with overharvesting, conservation efforts are required in this species. In this study, range-wide genetic structure of twelve D. malabaricum populations was evaluated to assess the impact of human activities on genetic diversity and infer the species' evolutionary history, using both nuclear and chloroplast (cp) DNA simple sequence repeats (SSR). As genetic diversity and population structure did not differ among seedling, juvenile and adult age classes, reproductive success among the old-growth trees and long distance seed dispersal by hornbills were suggested to contribute to maintain genetic diversity. The fixation index (F IS) was significantly correlated with latitude, with a higher level of inbreeding in the northern populations, possibly reflecting a more severe ecosystem disturbance in those populations. Both nuclear and cpSSRs revealed northern and southern genetic groups with some discordance of their distributions; however, they did not correlate with any of the two geographic gaps known as genetic barriers to animals. Approximate Bayesian computation-...