薇甘菊柄锈菌生物学及其寄主专一性

Biology and Host Specificity of Puccinia spegazzinii, a Potential Biocontrol Agent for Mikania micrantha

在检疫温室条件下对外来入侵植物薇甘菊的寄生菌——薇甘菊柄锈菌的生物学及其寄主专化性进行了研究。结果表明，薇甘菊柄锈菌可以侵染植物叶片和叶柄等营养器官。受侵染部位起始出现褪绿斑，12～15d，自叶背产生黄色冬孢子堆，并逐步坏死和脱落，最终致寄主死亡。冬孢子黄至暗褐色，包埋在寄主组织中，无明显休眠期。高湿条件下，冬孢子易萌发产生担孢子进行再侵染。采用悬挂法对29个科、62个属的72种植物进行了寄主专化性测定，结果表明，薇甘菊柄锈菌在菊科植物天门冬、紫茎泽兰、向日葵、地胆草上形成褪绿斑，但未发现菌丝和吸器。薇甘菊柄锈菌可成功侵染薇甘菊和同属植物假泽兰。

Biology and specificity of Puccinia spegazznii, a potential biocontrol agent of invasive weed, Mikania micrantha, were investigated under quarantine greenhouse in China. As an obligate parasite with short-cycled autoecious, it completed life cycle on Mikania mictantha by teliospores and basidiospores. It infected leaves, petioles and other vegetative organs of the host plant infected parts became chlorosis after inoculation for 4 - 5 d. Twelve to fifteen days later, yellow telia appeared from back of in- fected leaves. The infected leaves died and/or defoliated. Teliospore was yellow to brown color without dormancy. 72 species of plant, belonging to 29 families, 62 genera, were tested for infection. They were divided into 12 groups in the testing program. M. micrantha was used as CK plant in each group. Three replicates were settled. Inoculation method of the pathogen was in line with the sequence and regulation of the Centre for Agriculture and Bioscience International. Result showed that chlorosis spot appeared on Asparagus cochinchinensis, Eupatorium adenophorum, Elephantopus scaber and Helianthus annuus.However, no mycelium and hostorium were found. It is recognized that the fungus infected Mikania micrantha and M. cordata in China.