玉蜀黍黑粉菌担孢子萌发及侵染过程的研究

Studies on Germination And Infection of Basidiospores of Corn Smut Fungi

从担孢子的体外萌发,人工接种方法、萌发,侵染和扩展过程的扫描电镜及乳酚油组织透明法观察几个方面研究了相互亲和的基因型的玉蜀黍黑粉菌担孢子培养物。结果表明(1)担孢子体外环境水份的连续蒸发和丧失可能是担孢子萌发的决定性因素;(2)玉蜀黍黑粉菌的质配及双棱菌丝体的形成需要在寄主组织内的特珠环境下才能完成;(3)注射接种是用担孢子诱发玉米苗发病的最有效的方法,其技术关键是让悬浮液自苗基部注入沿未展开的叶束上升到顶部苗心溢出;(4)担孢子的萌发及侵入完成于接种后3～24h;(5)接种后4～6d 左右,寄主肿瘤出现前,受侵杂组织内已充满网状的双棱菌丝体。

Studies were made on the germination and the infection process of the compatible genotypes of basidiospores culture of Ustilago maydis with the germination in vitro, artificial inoculation method,observations on the germination,infection and the pathogen devolopment in host tissue by scanning electron microscope or iacphenol technique of tissue transparency.The results indicate that:the prossess of evaporation and the lose of water occured around the basidiospores may be a critical factor to the germination of the basidiospores;the cytoplasma mating of Ustilago maydis and the formation of the binucleate mycelium demand the specific enviroment in the host tissue;the injection inoculation on the base of the seedling is the most effective method to induce the corn smut disease,the key technique is to let the suspension to rise from the base to head along the unopened leaf roll and to overflow;the germination of the basidiospores and the invasion complete during the period around 3 to 24 hours after the inoculation;the infected host tissue was fulifilied with the networks of the binucleate mycelium about 4 to 6 days after the inoculation before tumour appeared.