白藓茎点霉叶斑病菌的生物学特性及药剂敏感性

对我国新见白藓茎点霉叶斑病的症状进行了描述,结合病原形态特征、培养特性及rDNA-ITS序列分析结果,确定该病害由Phoma dictamnicola引起。病菌的生物学特性研究结果表明:病菌菌丝在10~30℃可生长,25℃为最适生长温度;在pH 4~11可生长,pH为7时最适合菌丝生长;在马铃薯葡萄糖琼脂培养基上菌丝生长最快,在水琼脂培养基上菌丝生长最慢;在以葡萄糖为主要碳源和蛋白胨为主要氮源的培养基上生长最好。病菌对50%咪鲜胺乳油、10%苯醚甲环唑水分散粒剂、40%氟硅唑乳油、50%醚菌酯水分散粒剂敏感性较高,其EC500.1μg/m L;其次为250 g/L吡唑醚菌酯乳油和25%丙环唑乳油,0.1μg/m LEC501.0μg/m L。

Biological Characteristics and Fungicide Susceptibility of Pathogens of Dictamnus dasycarpus Leaf Spot

The symptoms of Dictamnus dasycarpus leaf spot were described in this study.Based on morphological and cultural characteristics of the isolates and results of its sequence analysis,the pathogen was identified as Phoma dictamnicola.The analysis results of biological characteristics of the pathogen showed that the suitable temperature for mycelial growth was 10-30 ℃,and 25 ℃ was the optimal.The pathogen could grow on the medium with pH from 4 to 11,and 7 was the optimal.The optimal medium for mycelial growth was PDA.Glucose and peptone were optimal for mycelial growth.The susceptibility of 10 fungicides to Phoma dictamnicola was detected by mycelial growth rate method.The results showed that the pathogen was more sensitive to 50％ prochloraz EC,10％ difenoconazole WG,40％ flusilazole EC,and 50％ KresoxiM-Methy WG(EC50＜0.1 μg/mL);followed by 250 g/L pyraclostrobin EC and 25％ propiconazole EC (0.1 μg/mL＜EC50＜ 1.0 μg/mL).