Identification of Pathogen in Brown Spot Disease from Guizhou Paris polyphylla var.yunnanensis and Toxicity Determination of 10 Bactericides
[Objective]The pathogen in brown spot disease from Guizhou Paris polyphylla var.yunnanensis was explored,and the effective fungicides for preventing and controlling brown spot disease in P.polyphylla were screened,which provided for the scientific basis for effectively controlling and preventing brown spot disease in P.polyphylla.[Method]The pathogen were isolated from the leaves of the infected plants of P.polyphylla in Zhijin,Guizhou,and then they were identified as Fusarium avenaceum by morphology,rDNA-ITS and β-tubulin gene phylogenetic analysis.The inhibitory effects of 6 chemical fungicides such as 40％pylocyanonitrile SC and 40％difenoconazole SC and 4 biological fungicides such as 80％ethylicin EC and 3％zhongshengmycin WP were determined by mycelial growth rate method.[Result]The pathogen was determined as F.avenaceum.All 10 fungicides inhibited the mycelial growth of F.avenaceum to varying degrees,and the relative inhibitory rate was positively correlated with the pesticide concentration.40％difenoconazole and 50％carbendazim had the best antibacterial effect,with their EC50 of 0.027 9 mg/L and 0.520 7 mg/L.Among the biological agent,0.3％eugenol had the best antibacterial effect,with the EC5o of 6.828 8 mg/L.[Conclusion]The pathogen in brown spot disease from Guizhou P.polyphylla was identified as F.avenaceum.In the field,40％difenoconazole,50％carbendazim and 0.3％eugenol could be used alternatively or in combination as candidate agents to improve their efficacy and avoid the development of resistance.
Paris polyphyllabrown spot diseaseFusarium avenaceumfungicidestoxicity deter-mination
NETL
NSTL
万方数据
维普
