十种虫生真菌液体培养芽生孢子的形态发生

芽生孢子是许多真菌通过出芽方式产生的无性孢子，在液体发酵中主要以这种形式大量繁殖。真菌杀虫剂活性成分分生孢子的大量生产使用液体发酵得到的芽生孢子作为接种物，另外，它也是当今虫生真菌遗传转化的重要受体，因而研究虫生真菌芽生孢子的形态和发生特点具有重要意义。本研究分别对液体发酵中的球孢白僵菌、粉棒束孢、蝉棒束孢、环链棒束孢、玫烟色棒束孢、细脚棒束孢、斜链棒束孢、金龟子绿僵菌、蝗绿僵菌和蜡蚧霉等10种常见虫生真菌芽生孢子的形成过程进行显微观察，了解其分生孢子产生过程的异同。结果表明，芽生孢子的产生方式有两种类型：1）蝉棒束孢在其整个生活史中以菌丝生长为主，芽生孢子产生的数量很少。2）其他各种真菌芽生孢子产生方式相似，在菌丝体形成后就开始大量以菌丝出芽或缢缩产生芽生孢子，接着还可通过芽生孢子的出芽或缢缩断裂产生新的芽生孢子。芽生孢子的产生分为3个时期：初期先由菌丝形成芽生孢子；指数期芽生孢子大量增殖，菌丝和芽生孢子都可产生芽生孢子；后期以芽生孢子产新芽生孢子为主要方式。

Morphogenesis of blastospores of ten species of entomopathogenic fungi

Blastospores are asexual fungal spores produced by budding and they are the main propagules in liquid culture for many fungi. They have been used as inoculum for solid culture for massproduction of fungal insecticides and also as an important receptor for current genetic transformation of entomopathogenic fungi. The morphogenesis of blastospores of 10 species of entomopathogenic fungi in liquid culture was studied, including Beauveria bassiana, Isaria farinosa, I. cicadae, I. cateniannulata, I. fumosorosea, I. tenuipes, I. cateniobliqua, Metarhizium anisopliae, M. acridum and Lecanicillium lecanii. The results showed two patterns of morphogenesis. I. cicadae mainly propagate as mycelium in liquid culture while the morphogenesis of the other 9 species in the liquid culture were similar and all involved two manners: yeast-like budding or hypha and/or blastospore constrictions. The second pattern included initial phase, exponential phase and senescence phase. In initial phase, blastospores were generated by budding or constriction of mycelium. In exponential phase, they were massively produced by budding or constriction of both mycelium and blastospores. In senescence phase, new blastospores were produced by blastospore budding.