分别应用3个稻曲病菌菌株ZJ09、XS14、XS1214,以及马铃薯蔗糖琼脂(potato sucrose agar,PSA)固体培养基、马铃薯葡萄糖琼脂(potato dextrose agar,PDA)固体培养基、TB3固体培养基和马铃薯蔗糖(potato sucrose,PS)液体培养基,进行固体或液体培养,实验结果表明补充0.250～0.500 g·L-1 L-半胱氨酸对稻曲病菌菌丝生长具有明显的抑制作用,作用强度随L-半胱氨酸浓度提高而增加.分别采集未补充L-半胱氨酸和补充0.250 g-L1 L-半胱氨酸的PSA固体培养基平板上培养6 d的两组ZJ09菌丝进行转录组测序,得到2 138个差异表达基因(differentially expressed genes,DEGs),其中985个被L-半胱氨酸上调表达,1 153个被L-半胱氨酸下调表达.针对转录组测序结果获得的6个DEGs进行了 RT-qPCR验证.GO富集结果显示,DEGs在细胞组分、分子功能和生物过程3个类别中均有富集,说明L-半胱氨酸抑制菌丝生长机制复杂.KEGG通路注释结果表明,L-半胱氨酸抑制菌丝生长可能主要与其影响内质网中蛋白质的加工有关.分析DEGs功能后还发现,L-半胱氨酸显著削弱菌丝中几丁质合酶D、细胞分裂控制蛋白6(cell division control protein,CDC6)及细胞分裂控制蛋白48(CDC48)编码基因的表达,推测可能与其对稻曲病菌菌丝生长的抑制作用有关.

为了解2019年浙江省小麦赤霉病菌的种群组成及其对杀菌剂的敏感性,调查了浙江省3个地区(杭州市萧山区、杭州市桐庐县、宁波市象山县)麦田的稻桩带菌率和小麦病穗率,利用PCR和DNA测序技术鉴定病菌的种群组成.结果显示,3月份3个地区田间稻桩的赤霉病菌子囊壳携带率为26.4％～55.4％,其释放的子囊孢子能正常萌发长出菌丝并快速形成菌落;小麦田间3月份空气中赤霉病菌游动孢子数量最多,4-5月份数量有所下降;田间小麦于4月份中旬开始出现病穗,4月下旬病穗率快速攀升;从386个分离菌株中随机选择的32个菌株均被鉴定为亚洲镰孢菌(Fusariuimi asiaticum);72个菌株被认定为多菌灵(10 mg·L-1)抗性菌株,约占分离菌株的18.65％.采用菌丝生长速率法检测16个分离菌株对杀菌药剂的敏感性,发现75％肟菌·戊唑醇水分散粒剂和30％唑醚·戊唑醇悬浮剂对分离菌株的EC50值(有效抑制中浓度)均低于5.0 mg·L-1,40％戊唑·咪鲜胺微乳剂和25％氰烯菌酯悬浮剂对分离菌株的EC50 值均低于2.0 μL·L-1,表明上述4种药剂的抑菌效果均良好;进一步对这4种杀菌药剂进行两两混配,检测对16个分离菌株的抑菌效果,发现混配方案"75％肟菌·戊唑醇水分散粒剂"+"30％唑醚·戊唑醇悬浮剂"对分离菌株的抑菌效果最强.

With the aim of exploring the regulating factors and involved mechanisms for the growth of Villosiclava virens mycelia, a strain (ZJ09) of this fungus was cultured on potato sucrose agar (PSA) plates under dark and lighting (with white light from fluorescents) conditions, respectively, and the growth states of the colonies were compared. A significant inhibitory effect was observed by lighting on the growth of V. virens mycelia, which suggested that lighting condition was a regulating factor for the mycelial growth of this fungus. The mycelial samples of the fungal strain ZJ09 from the dark and lighting groups were collected and their transcriptomes were sequenced, respectively. Six hundred and ninety-five differentially expressed genes (DEGs) caused by lighting were identified, including 359 up-regulated genes and 336 down-regulated ones. Six DEGs were selected out to check by real-time quantitative polymerase chain reaction (RT-qPCR) and the expression results were consistent with those by transcriptomic sequencing. During gene ontology (GO) enrichment analysis, 491 of the 695 DEGs were enriched to the terms of biological process, cellular component and molecular function, indicating that complex mechanisms may be involved in the inhibitory effect of lighting on mycelial growth. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis results of the 695 DEGs indicated that influences on the structure and functions of ribosome, and amino acid metabolism were quite probably involved in the inhibitory effect of lighting on mycelial growth. As DEGs included a gene encoding acetyl-coenzyme A synthetase and the lighting condition significantly inhibited its expression, it was inferred that impairing the mycelial acetyl-coenzyme A synthesis ability was one of mechanisms of the inhibitory effect of lighting on mycelial growth. In contrast, as neither of the genes UvHOG1 and UvBI-1 was a DEG, the protein kinase HOG1 (high osmolarity glycerol 1) and Bax inhibitor-1 may both have nothing to do with the inhibitory effect of lighting on mycelial growth.