应用ISSR 技术分析杧果畸形病病原菌的遗传多样性

为探索我国杧果畸形病病原菌的遗传多样性,运用ISSR分子标记技术分析了采自四川攀枝花市和云南华坪县的38个杧果畸形病病原菌的遗传多样性.供试的38个菌株经14条特异性引物共扩增出72条带,其中52条带具有多态性,多态性比率为72.22％.38个菌株的相似系数值为0.5972～0.9862,变幅为0.3889,平均为0.7885.其中菌株MG16与MG17的相似系数最大、为0.9862;菌株MG07和MG33的遗传相似系数最小、为0.5972.利用UPGMA法进行聚类分析,38株菌株在相似系数为0.76水平上分为5类,菌株MG33、MG07和MG36分别形成单一分支,MG25和MG35聚合在一起;其余菌株分布在第V类中.我国杧果畸形病病原菌Fusarium mangiferae存在丰富的种资资源,且F.mangiferae与采集地点、杧果品种之间无明显相关性.

Study on genetic diversity of Fusarium mangiferae frommango malformation disease by ISSR analysis

In order to explicit the genetic diversity of 38 strains Fusarium mangiferae from mango malformationdisease from Panzhihua, Sichuan, and Huaping, Yunnan in China, the ISSR technique was used. 72 bands were amplifiedby 14 ISSR primers, with an average of 5.14 bands per primer. The size of the amplified products ranged from 300 bp to2 000 bp. The genetic similarities among isolates ranged from 0.5972 to 0.9862. Isolates MG16 and MG17 were the mostsimilar(0.9862 genetic similarity), whereas isolates MG07 and MG33 were the least similar(0.5972) and were grouped inseparate clusters. At a genetic similarity of 0.76, the unweighted pair -group method with arithmetic mean analysisseparated the isolates into five distinct clusters, comprising 33, two, one, one and one isolate, respectively. The ISSR datasupported the conclusion that the isolates of F. mangiferae were not necessarily related by geographic origin, type of tissueor the mango cultivar from which they were isolated. This is the first report on the diversity of F. mangiferae speciesassociated with mango malformation in China.