台湾虫草的被毛孢无性型新种及其对黄粉虫的侵染研究

报道采自安徽省黄山风景区的台湾虫草Cordycepsformosana,多批次收集弹射的子囊孢子分离得到其无性型,经鉴定为一被毛孢新种,命名为黄山被毛孢Hirsutellahuangshanensis。黄山被毛孢在米饭培养和自制的虫草培养基上均能长出子实体,其菌落及子实体颜色与天然虫草较为相似,但未见成熟的子囊壳。应用黄山被毛孢RCEF0868菌株对饲喂昆虫黄粉虫进行感染试验,结果表明:黄粉虫在菌落接触感染、刚蜕皮幼虫的穿刺接种和孢子浓度1.0×107/ml浸蘸处理下,获得了相对较高的侵染率,分别达到30%、25%和25%,刚蜕皮幼虫一般比深色幼虫组其侵染率较高,1×105/ml孢子浓度浸蘸试虫不论是刚蜕皮或老熟幼虫均不能感染。10d后被感染的黄粉虫形成僵虫,继续保湿培养20d后,体表节间膜处形成白色菌膜,粘片镜检表明感染真菌即为供试菌株。40d后,可见子实体原基及孢梗束,尚未见成熟的子囊壳。

HIRSUTELLA HUANGSHANENSIS SP.NOV., THE ANAMORPH OF CORDYCEPS FORMOSANA AND ITS INFECTION ON TENEBRIO MOLITOR

Hirsutella huangshanensis sp. nov. originated from secondary ascospores of Cordyceps formosana collected from Huangshan Mountain of Anhui Province was regarded as the anamorph of the fungus. The typical characteristics of the new anamorph were described. Some immature stromata formed on an artificial medium were obtained. Their shape and color were similar to those of natural stromata. RCEF0868, a strain of Hirsutella huangshanensis, was applied to infect Tenebrio molitor. The primary results showed that Tenebrio molitor could be infected by giving the insect larvae a touch on the colony of the strain, puncture inoculation into new-ecdysis larvae or dipping the larvae in the conidium suspension of concentration of 1.0×107 /ml. Infection rates attained 30%, 25% and 25% respectively. However, in the conidium suspension of concentration of 1×105 /ml the new-ecdysis larvae or dark colored insects could not be infected by dipping inoculation method. After 10 days the infected insects became stiff. When the stiff insects were cultured at certain moisture for 20 days, white velum was formed at conjuctiva. After 40 days incubation the stromata were formed, but perithecia were not found.