甘蔗黑穗病菌（Ustilago scitaminea Syd.）分子多样性初步分析

摘要：应用经筛选的13条10 bp随机引物，对来自福建等6个省（区）甘蔗(Saccharum ssp.)上的18个甘蔗黑穗病菌（Ustilago scitaminea）分离物进行了RAPD分析。来自福建和广西的2个代号分别为7和9的分离物间，显示出最大的相异系数为0.89474； 最小相异系数为0.25217, 是在两个福建分离物间出现的。UPGMA聚类结果表明，18个分离物在0.75的相异水平上可以聚为6个群体，7个来自不同寄主品种的福建分离物相异系数较小，分布于2个相邻的遗传聚类群中，同时，2个来自同一寄主品种不同地理来源的分离物间，显示出高达0.82353的相异系数。说明分子多样性同地理来源之间具有一定的相关性，但与寄主来源无关。

Primary Analysis of Molecular Diversity in Populations of the Fungus Ustilago scitaminea Syd.

Abstract: Eighteen isolates were obtained from sugarcane smut fungus (Ustilago scitaminea Syd). cultivated in six different provinces or regions including Fujian Province. On the basis of isolation of single spore and the acquisition of series of the isolates, 13 random primers of 10 bp were occupied in analysis of genetic diversity by RAPD. The largest dissimilarity coefficient was 0.89474, being observed in two isolates with codes of 7 and 9 originated from Fujian and Guangxi, respectively; the smallest value of 0.25217 was observed in two isolates originated in Fujian. Dendrogram of UPGMA cluster analysis revealed that 18 isolates of U. scitaminea Syd. were divided into 6 groups according to the dissimilarity coefficient of 0.75. Because of small dissimilarity coefficient, seven isolates obtained from sugarcane in Fujian Province belonged to two adjacent groups of cluster Ⅰ and cluster Ⅱ. High dissimilarity coefficient of 0.82353 was observed in two isolates collected from same host origin but with different geographical origin.The results of cluster suggested that the molecular diversity was associated with geographyic origins in some degree, but not related to host origin.