化学杀菌剂对植物病原菌和生防菌MT-06的选择毒性

Selective Toxicity of Chemical Fungicides to Phytopathogenic Fungus and Bbiological Control Strain MT-06

研究了6种化学杀菌剂对7种植物病原菌和生防菌株MT-06的选择毒性,结果表明:代森锰锌对番茄早疫病菌、水稻立枯丝核菌及甜瓜蔓枯病菌三种病原菌的TSR值(益害生物毒性选择性比值)分别为4.5946、4.4536和2.2885,表明有正向选择性(TSR>1)。百菌清对水稻立枯丝核菌和甜瓜蔓枯病菌的TSR值分别为12.9743和18.2633,具有正向选择性。甲霜锰锌对番茄早疫病菌、茭白胡麻斑病菌、水稻立枯丝核菌及甜瓜蔓枯病菌的TSR值分别为13.9277、13.9277、2.89和2.4596,具有正向选择性。这三种化学杀菌剂可作为与生防菌株MT-06混配的备选药剂进行相应病害的防治试验。防治番茄早疫病盆栽试验结果表明:MT-06和化学杀菌剂混配与单独施用化学杀菌剂相比,在达到相近防治效果的情况下,可大幅降低化学药剂的使用量;适量的化学杀菌剂和MT-06混配与单独施用MT-06相比,对番茄早疫病的防治效果显著增强。

Six chemical fungicides were used to evaluate their selective toxicity to 7 phytopathogenic fungus and biocontrol strain MT-06. Results indicated that mancozeb exhibited great inhibition against Alternaria solani, Rhizoctonia solani and Didymella bryoniae, respectively. The TSR （selective toxicity ratio） values of mancozeb against Alternaria solani, Rhizoctonia solani and DidymeUa bryoniae ranged from 2.2885 to 4.5946, which implied the existence of positive selection. The TSR values of chlorothalonil against R. solani and D. bryoniae were 12.9743 and 18.2633, with a moderate positive selection. The TSR values of metalaxyl mancozeb agaist A.solani, Helminthosporium zizaniae, R.solani and D.bryoniae were 13.9277, 13.9277, 2.89 and 2.4596, respectively. These three kinds of chemicalfungicides can be used as alternative fungicides mixed with biocontrol strain MT-06 to experiments of controlling corresponding diseases. Pot experiments of A.solani showed that MT-06 and chemical fungicide mixture compared with single application of chemical fungicides, achieve similar control effect, can greatly reduce the use amount of chemical; the proper amount of chemical fungicides and MT-06 mixed compared with single application of MT-06, control effect on A.solani was improved significantly.