翡翠景天黑腐病菌山扁豆生棒孢生物学特性及室内药剂筛选

Biological Characteristics and Fungicides Screening in Laboratory of Corynespora cassiicola Causing Sedum morganianum Black Rot

为明确多肉植物翡翠景天黑腐病病原菌山扁豆生棒孢(Corynespora cassiicola)的生物学特性,分别测定温度、pH、光照条件和碳、氮源对菌丝生长的影响,以及通过测定6种杀菌剂对该病原菌的室内毒力,筛选出高效安全的杀菌剂。结果表明:该病原菌的菌丝生长最适温度为30℃,最适pH为7,光照有利于菌丝生长,最适碳、氮源分别为葡萄糖和蛋白胨。室内毒力测定结果表明,6种杀菌剂对翡翠景天黑腐病病原菌的毒力差异较大,其中氯氟醚菌唑的毒力最强,EC_(50)为0.0129 mg/L;其次为咪鲜胺,EC_(50)为0.0135 mg/L;苯醚甲环唑和咯菌腈的EC_(50)分别为0.0273 mg/L和0.0296 mg/L;吡唑醚菌酯的毒力一般,EC_(50)为0.0768 mg/L;多菌灵的毒力最弱,EC_(50)为0.9353 mg/L。掌握山扁豆生棒孢的生物学特性和筛选出室内具有良好毒力效果的药剂,可为多肉植物翡翠景天的栽培及其黑腐病的综合防治提供理论支撑和指导依据。

In order to research the biological characteristics of the pathogen and fungicide screening for Sedum mor-ganianum of Corynespora cassiicola,the effects of temperature,pH,light condition and different carbon and nitrogen sources on mycelial growth were studied with the mycelial growth rate method,and the toxicity measurement of six fungicides to C.cassiicola was determined.The results showed that the optimum temperature for the mycelial growth of the pathogen was 30℃,the optimum pH for mycelial growth was 7,light was conducive to mycelial growth,the opti-mum carbon was glucose and nitrogen source was peptone.Toxicity measurement results showed that the six fungicides had different toxicity on the pathogen of C.cassiicola.Among them,the toxicity of mefentrifluconazole was the best,with EC_(50)0.0129 mg/L,followed prochloraz,with EC_(50)0.0135 mg/L.The toxicity of difenoconazole and fludioxonil were strong,with EC_(50)0.0273 mg/L and 0.0296 mg/L respectively.The toxicity of pyraclostrobin was mild,with EC_(50)0.0768 mg/L.The toxicity of carbendazim was the weakest,with EC_(50)0.9353 mg/L.The study could provide a theo-retical basis and guidance for the cultivation of succulent plants and the comprehensive management of black rot.