两种白莲叶斑病病原菌室内药剂筛选

Fungicide Screening of Two Pathogens Causing White Lotus Leaf Spots

【目的】白莲是江西省广昌县重要的经济作物,种植广泛,在农业发展中占据重要地位。白莲病害危害严重,对莲子的产量和质量造成潜在影响。研究拟通过室内毒力测定筛选到对白莲叶斑病有效的防治药剂,为白莲病害的综合防治提供理论基础。【方法】采用生长速率法测定了3种杀菌剂对白莲叶斑病2种病原菌梨形黑孢菌和链格孢菌的室内毒力。【结果】所选的3种杀菌剂均对梨形黑孢菌和链格孢菌有一定的抑菌作用。对于链格孢菌,抑制效果最好的是56%啶酰肟菌酯和45%咪鲜胺,其EC50值分别为8.294μg/mL和8.371μg/mL。对于梨形黑孢菌,45%咪鲜胺抑制效果最好,EC50为11.488μg/mL;其次为56%啶酰肟菌酯和40%苯醚甲环唑,EC50分别为20.592μg/mL和59.476μg/mL。【结论】56%啶酰肟菌酯对链格孢菌的杀菌效果较好,45%咪鲜胺对梨形黑孢菌的杀菌效果较好。

[Objective]White lotus is an important cash crop in Guangchang County,Jiangxi Province.This crop is widely planted and plays an important role in agricultural development.The diseases of white lotus are serious and make a potential impact on the yield and quality of lotus seeds.In this study,effective fungicides were preliminarily screened through indoor toxicity test to provide a theoretical basis for the integrated control of white lotus diseases.[Method]The indoor toxicity of three fungicides against Alternaria alternata and Nigrospora pyriformi were determined by the mycelial growth rate method.[Results]These three selected fungicides all had inhibitory effects on A.alternata and N.pyriformi.As for A.alternata,both 56%acetaminoxim ester and 45%prochloraz had the best inhibition effects,and their EC50 values were 8.294μg/mL and 8.371μg/mL,respectively.As for N.pyriformi,45%prochloraz had the best inhibition effects with EC50 of 11.488μg/mL,followed by 56%acetaminoxim ester and 40%difenoconazole,with EC50 of 20.592μg/mL and 59.476μg/mL,respectively.[Conclusion]56%acetaminoxim ester had better effects on A.alternata,while 45%prochloraz had better effects on N.pyriformi.