油梨根腐病病原菌的鉴定、生物学特性及室内药剂筛选  

Identification,Biological Characteristics and Screening of Fungicides of the Pathogen Causing Root Rot on Avocado(Persea americana)

作　　者：仇芳 徐刚[1] 谢昌平[1] 李希 郑妃庆 QIU Fang;XU Gang;XIE Changping;LI Xi;ZHENG Feiqing(College of Plant Protection,Hainan University/Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests,Ministry of Education,Haikou,Hainan 570228,China)

机构地区：[1]海南大学植物保护学院/热带农林生物灾害绿色防控教育部重点实验室,海南海口570228

出　　处：《热带作物学报》2021年第5期1424-1432,共9页Chinese Journal of Tropical Crops

基　　金：海南大学植物保护学院学生学术科技创新支持项目(No.Hys2019-97)。

摘　　要：根腐病是油梨的毁灭性病害之一,该病害为害根部,引起根部变黑腐烂,严重时导致植株死亡。从发病典型的植株根部分离、纯化菌株,并开展致病性测定、形态学特征和多基因位点(ITS、LSU和COXⅡ)系统发育树分析相结合的病原菌鉴定。结果表明,引起海南油梨根腐病的病原菌为樟疫霉(Phytophthora cinnamomi)。还研究了不同培养条件和10种药剂对病原菌菌丝生长的影响。结果表明,病原菌在PDA培养基上生长较好,最适生长温度为28℃,最适pH为8,黑暗条件更适合病原菌的生长;烯酰吗啉对病原菌的抑制作用最强,EC50为0.0929μg/mL。本研究结果为油梨根腐病的田间防控提供了一定的理论依据。Root rot of avocado is one of the destructive diseases.The disease infects the root system of plants,causing serious black rot of roots,leading to the death of plants.The strain was isolated and purified from the roots of typical symptoms and identified by the pathogenicity test,morphological characteristics,and multi-loci(ITS,LSU,and COXⅡ)phylogenetic analyses methods.The result showed the root rot of avocado from Hainan was caused by Phytophthora cinnamomi.To clarify the biological characteristics and sensitivity to ten fungicides,the effects of different culture condition on the hypha growth of P.cinnamomi were determined,and the inhibitory activities of ten fungicides on P.cinnamomi were also studied.The results exhibited that PDA medium was the appropriate medium for hypha growth,the optimum temperature was 28℃,the suitable pH was 8,and continuous darkness condition was beneficial to hypha growth.The toxicity test showed that dimethomoph had the best inhibitory activity with EC50 of 0.0929μg/mL among the fungicides.The result could provide a theoretical basis for the field control of avocado root rot disease.

关 键 词：油梨 根腐病 樟疫霉 

分 类 号：S436.67[农业科学—农业昆虫与害虫防治]