甘草根腐病病原鉴定及室内毒力测定

对甘草根腐病的病原进行分离鉴定，并采用菌丝生长速率法分别测定苯醚甲环唑、多菌灵、甲基硫菌灵、嘧菌酯、多·福·溴菌腈、百菌清、咪鲜胺、代森锰锌和恶霉灵9种杀菌剂对该病原菌丝的室内毒力。结果表明，甘草根腐病的主要病原为尖孢镰孢菌（Fusarium oxysporum）。9种药剂对病菌菌丝的EC₅₀为：咪鲜胺<苯醚甲环唑<多·福·溴菌腈<多菌灵<百菌清<嘧菌酯<甲基硫菌灵<恶霉灵<代森锰锌。咪鲜胺对菌丝生长的抑制作用最强，EC₅₀值为0.002 mg/L；代森锰锌最弱，EC₅₀值为117. 175 mg/L。其中咪鲜胺、苯醚甲环唑、多·福·溴菌腈的EC₅₀均小于1 mg/L。

Identification of Root Rot Pathogen of Glycyrrhiza and Indoor Toxicity Text

The root rot pathogens of Glycyrrhiza were isolated and identified, and toxicity of nine fungicides was tested by means of mycelia growth method in the laboratory. The results showed that the main root rot pathogen of Glycyrrhiza was Fusarium oxysporum. The mycelial growth method showed that the EC₅₀ of the 9 fungicides could be arranged in descending order as prochloraz, difenoconazole, carbendazim·thiram·bromothalonil, carbendazim, chlorothalonil, azoxystrobin, thiophanate methyl, hymexazol, and mancozeb. The inhibitory strongest effect was detected in prochloraz treatment within the EC₅₀ of 0.002 mg/L and the weakest effect in mancozeb treatment with the EC₅₀ of 117.175 mg/L. The EC₅₀ of prochloraz, difenoconazole and carbendazim·tetramethylthlthiuram disulfide·bromothalonil were less than 1 mg/L.