鄂尔多斯高原不同降雨量地区中间锦鸡儿(Caragana davazamcii Sancz)种群的ISSR遗传分析

Genetic Analysis Based on ISSR of Caragana davazamcii Sancz Popula-tions in Different Precipitation Areas in Erdos Plateau

采用简单重复间序列(ISSR)方法,对鄂尔多斯高原从东向西降雨量逐渐减少选5个地区的中间锦鸡儿种群进行分子生态学研究的结果表明,随着这一地区多年平均降雨量由东向西的逐渐减少,中间锦鸡儿种群遗传多样性有所增加,大部分变异发生在种群内(79.95%),属异交类型,中间锦鸡儿群体间遗传距离缓慢增加,遗传一致度降低。这种随着水分递减呈现生态梯度变异的现象,说明水分变化特别是长期形成的水分条件对中间锦鸡儿的遗传多样性可能有一定的影响。

The results showed that the Nei＇s gene index and Shannon＇s information index increased along with changes of the habitats from east to west and with lack of average annual rainfall, as well as genetic diversity increased. It was found that total genetic diversity of five populations （HT） was 0.2963, genetic diversity within populations （Hs） was 0.2269, genetic diversity among populations （DsT） was 0.0594, genetic differentiation coefficient （GsT） was 0.2005, and gene flow was 1.9936.79.95% of molecular variation in Caragana davazamcii Sancz existed within populations, while few of which existed among populations, so it belonged to hybridization. Genetic distance between five populations was small, but it increased slowly with changes of the habitats from east to west, while genetic identity decreased, it showed ecological gradient variation according to lack of water. All these indicated that moisture changes especially long-term moisture conditions formed had an effect on genetic diversity of C. davazamcii.