麦长管蚜自然群体的遗传变异研究

以8个不同地区的麦长管蚜(Macrosiphumavenae)种群为虫源,每种群10个个体用6种随机引物进行RAPD分析。结果表明,引物在8个种群间共产生272个RAPD标记,种群内的相似度比种群间的高得多。利用Nei氏相似系数,对8个种群的RAPD-PCR结果进行分析可知,北京与山东试虫采集地种群遗传距离为0.0239,在8个地区中最小,山西试虫采集地种群与其他7个地区差异最大,这说明不同地区的麦长管蚜(M.ave-nae)种群的确存在着遗传变异。用UPGMA法构建的聚类图发现,麦长管蚜聚成3个群体:山东和北京群体,安徽、四川和陕西群体,新疆群体,呈梯度分布,单纯以地理隔离不能解释麦长管蚜自然群体间的遗传变异。

Genetic polymorphism in natural populations of Macrosiphum avenae

Random amplified polymorphic (RAPD) techniques were apllied to characterize genetic variations in eight natural populations of Macrosiphum avenae.Six primers are selected from 28 primers.The result showed that the six primers proudued 272 RAPD markes,and similarity in geographic populations was higher than that among different geographic populations.RAPD data were used to analyze the genetic similarity of M.avenae,the result showed that mean divergence between Beijing and Shandong was only (0.023 9).The cluster analysis showed that geographical seclusion couldn't explain genetic distance,natural condition's influence was important to DNA gene flow of the natural population genetic variation of M.avenae.We suggest that there exists a latitudinal genetic variation in natural populations of M.avenae.