南方农业学报2024，Vol.55Issue(7)：2126-2136,11.DOI:10.3969/j.issn.2095-1191.2024.07.024
贵州省核桃叶斑病病原菌鉴定、生物学特性及防治药剂筛选
Identification and biological characteristics of walnut leaf spot disease pathogen in Guizhou and screening of fungicides
摘要
Abstract
[Objective]This study aimed to clarify the classification status and biological characteristics of the potho-gen of walnut leaf spot disease in Guizhou and screen effective fungicides,so as to provide theoretical basis for contro-lling the walnut leaf spot disease in the field.[Method]The leaves of walnut leaf spot disease collected from walnut plan-ting base in Hezhang,Bijie,Guizhou were used as materials.Tissue separation method was used to isolate and purify the pathogenic bacteria,and Koch's rule was used to determine the pathogenicity of the pathogen.The sequences of ITS,β-tubulin and TEF1-α genes in the pothogen were amplified respectively.Based on morphological characteristics and mul-tigenes sequence analysis,the pathogen was classified and identified.Biological characteristics of the pathogen was deter-mined by one-way variation method.Indoor toxicology test was conducted to evaluate the inhibtion effects of 17 common fungicides on leaf spot disease.[Result]Eighteen fungal isolates were obtained from the diseased walnut leaves in He-zhang,Bijie,Guizhou,and representative strain C5 was selected for morphological and pathogenicity determination.The pathogenicity detection results indicated that strain C5 was the pathogen causing walnut leaf spot disease.Morphological characteristics of strain C5 was similar to those of Fursarium equiseti,and multigenes cluster analysis showed that the pathogen was clustered in the same branch with F.equiseti yl-1.The optimum growth temperature of strain C5 was 20-25℃,the optimum photoperiod were 18 h∶6 h(light∶dark).Diverse carbon and nitrogen resources could be used,the optimum carbon source was sucrose,the best nitrogen source was beef paste.The germination rate of conidia was the highest under 70%humidity.Among the tested 17 fungicides,45%prochloraz ME,30%pyraclostrobin·tebuconazole SC,0.15%tetramycin AS,40%myclobutanil SC,10%difenoconazole WG and 1%phenazino-1-carboxylic acid SC had better inhibitory effects on the growth of strain C5 mycelium,and their median inhibitory concentrations(EC50)were 0.0006,0.0016,0.0046,0.0062,0.0084 and 0.0097 μg/mL respectively.[Conclusion]The pathogen of leaf spot disease from the walnut growing area in Hezhang,Bijie,Guizhou is F.equiseti.45%prochloraz ME or 0.15%tetramycin AS can be the first choice for controlling the disease,and 30%pyraclostrobin·tebuconazole SC,40%myclobutanil SC,10%di-fenoconazole WG and 1%phenazino-1-carboxylic acid SC can be used as alternative fungicides.关键词
核桃/叶斑病/木贼镰刀菌/生物学特性/药剂筛选/贵州省Key words
walnut/leaf spot disease/Fusarium equiseti/biological characteristics/fungicide screening/Guizhou分类
农业科技引用本文复制引用
敖显禧,欧阳浩,杨文佳,樊瑞冬,吕周乐,吴朝明,陈孝玉龙..贵州省核桃叶斑病病原菌鉴定、生物学特性及防治药剂筛选[J].南方农业学报,2024,55(7):2126-2136,11.基金项目
国家自然科学基金项目(32360705) （32360705）
贵州省高层次创新型人才项目(黔科合平台人才-GCC[2023]071) （黔科合平台人才-GCC[2023]071）
贵州省林业科研项目(黔林科合[2021]04号) （黔林科合[2021]04号）
贵州省教育厅重点实验室项目(黔教技[2023]024号) National Natural Science Foundation of China(32360705) （黔教技[2023]024号）
Guizhou High-level Innovation Ta-lents Project(QKHPTRC-GCC[2023]071) （QKHPTRC-GCC[2023]071）
Guizhou Forestry Science and Technology Research Project(Qianlinkehe[2021]04) （Qianlinkehe[2021]04）
Key Laboratory Project of Guizhou Education Department(Qianjiaoji[2023]024) （Qianjiaoji[2023]024）
