【摘要】 1980—1981年先后自北京、昆明、福州等地双孢蘑菇[Agaricus bisporus(Lange)Sing.]上分离到一种真菌,在PDA上的培养性状与蘑菇轮枝菌(Verticillium psalliotae Tresch.)和蛛网丝枝霉中国变种[Aphanocladium aranearum(Petch)Gams var.sinense J.D.Chen]近似。镜检可见其兼具上述两种菌的形态。经反复多次纯化,并挑取单孢子培养,肯定了这种真菌是纯菌。在培养基上已保存4年,形态稳定。它具典型蘑菇轮枝菌形态,而其丝枝霉型瓶梗的形成和瘪缩时间、长度、原瓶梗数量、末端瓶梗数及排列密度等,都与蛛网丝枝霉中国变种有一定差异,与丝枝霉属其它种亦不同,故定为两型丝枝霉新种(Aphanocladium dimorphum sp.nov.)。本文详细描述了该新种的形态,并对文中所提的五种真菌及其与Engyodontium属间的关系进行了讨论。更多还原

【Abstract】 An Aphanocladium species had been isolated from diseased Agaricus bisporus from Beijing, Kunming and Fuzhou, in 1980—1981. Its cultural characters on PDA and CzA are very similar to those of Verticillium psalliotae Tresch. and Aphanocladium aranearum var. sinense, but it shared both morphology of the above mentioned two fungi under the microscope. In the induced experiment of parasitism, repeated attempts were made to purify the fungus, and picking out a number of single spores with the aid of a micromanipulator, the morphology of both morphs appeared consistently from either single colony or single spore culture. The possibility of parasitic relationship or mixed culture of both fungi was therefore excluded. In single spore culture of this fungus on PDA or CzA in 48 even 72 hours, only typical phialides of V. psalliotae appeared. As the culture was growing for 2—10 days continuously, the aphanocladiate morph arose everywhere. This peculiar type of morphology was very stable in the culture for four years. Since the morphology of the aphanocladiate morph in this fungus had some differences from A. aranearum var. sinense and other species in this genus, it was considered to be a new species, the name Aphanocladium dimorphum sp. nov. is proposed. So far, it was only obtained from A. bisporus collected from the above mentioned three cities in China. To compare the three fungi on PDA, CzA, MA (malt extract agar), PrA (prune agar), OA(oat meal agar) and Martin agar, and under four temperatures, 18, 22, 26, 30℃, we could not distinguish them from each other macroscopically. The number of phialides of aphanocladiate morph in this new species were influenced to some extent by the medium used. On PDA and CzA they were rather abundant than on other media, and the two morphs were all scanty on MA. But the mycelia were very thick on MA. The optimum growth temperature was 26℃, and then 22, 18, and 30℃ successively. The fruiting bodies of A. bisporus were inoculated with this fungus, there were no apparent difference in symptom or severity of the disease of the inoculated mushrooms caused by V. psalliotae and A. aranearum var. sinense separatly. As the optimum growth temperature of this fungus is much higher than A. bisporus, so we estimate that it may not cause a severe damage by itself alone. In the present paper, the morphology of this fungus is described in detail. The pleomorphic imperfect fungi, the correlation among the above mentioned three fungi and genus Engyodontium are discussed.更多还原