Table_1_Taxonomy and control of Trichoderma hymenopellicola sp. nov. responsible for the first green mold disease on Hymenopellis raphanipes.DOCX

Trichoderma spp. are a group of widespread fungi with important applications in many aspects of human life, but they are also pathogens that cause green mold disease on mushrooms. During a survey of mushroom cultivation in Guizhou, China, five strains of Trichoderma from three different localities were isolated from soil in mushroom bags of Hymenopellis raphanipes. The typical morphology of having gregarious, reddish stromata and gregarious phialides and the results of phylogenetic analyses based on a combined dataset of RPB2, TEF, and ITS gene sequences demonstrated that these green-spored Trichoderma belong to a new taxon, Trichoderma hymenopellicola. Pathogenicity tests by covering fungal mycelial blocks or soil mixed with spore suspension in mushroom bags showed similar symptoms to those in the field, and the same fungal pathogen had been observed and re-isolated from these symptoms, which fulfill Koch’s postulates. A primary screening test of nine common fungicides indicated that prochloraz-manganese chloride complex and propiconazole are the top two effective fungicides inhibiting the pathogen, whereas the former was further indicated as a suitable fungicide to control Trichoderma hymenopellicola, with a high inhibition ratio to the pathogen and low toxicity to the mushroom.

木霉菌属（Trichoderma）是一类分布广泛的真菌，在人类生活诸多领域具有重要应用价值，同时也是引发食用菌绿霉病的病原菌。在中国贵州开展的食用菌栽培调查中，研究人员从长根小奥德蘑（Hymenopellis raphanipes）菌包的土壤样本内，分离得到了来自3个不同产地的5株木霉菌。此类产绿色孢子的木霉菌具有丛生红褐色子座、丛生瓶梗的典型形态特征；结合RPB2、TEF与ITS基因序列联合数据集进行的系统发育分析结果表明，其为一新的分类单元，命名为小奥德蘑生木霉菌（Trichoderma hymenopellicola）。通过在菌包中接种真菌菌丝块或掺入孢子悬浮液土壤的方式开展致病性测定，所得发病症状与田间自然发病症状一致，且可从发病组织中重新分离得到该病原菌，符合科赫法则（Koch’s postulates）。对9种常用杀菌剂的初步筛选试验表明，咪鲜胺锰盐（prochloraz-manganese chloride complex）与丙环唑（propiconazole）对该病原菌的抑制效果位列前二；其中咪鲜胺锰盐对病原菌抑制率高且对食用菌毒性低，进一步被确定为防治小奥德蘑生木霉菌的适宜杀菌剂。