平贝母鳞茎腐烂病病原菌鉴定和药剂筛选

Identification of the pathogen of the bulb rot of Fritillaria ussuriensis and screening of the fungicides

为明确平贝母Fritillaria ussuriensis鳞茎腐烂病的病原菌及其防治,对病原菌进行分离、致病性测定,通过形态学特征、ITS rDNA、β-tubulin及EF-1α基因序列分析确定其病原为尖孢镰刀菌Fusarium oxysporum和芳香镰刀菌F.redolens。通过菌丝生长速率法,对病原菌进行了室内药剂筛选,表明8种药剂中25%多菌灵可湿性粉剂和43%戊唑醇悬浮剂对病原菌有更好的抑制作用,处理第6天,EC 50均不超过0.7 mg/L。对两种病原菌防效最好的药剂是戊唑醇,EC 50分别为0.107、0.169 mg/L。这两种药剂可以选择应用于平贝母生产来防治茎腐病。

To make clear the fungal pathogen species of the bulb rot of Fritillaria ussuriensis and the control,pathogens were isolated and their pathogenicities were tested.Based on morphological characteristics,ITS rDNA,β-tubulin and EF-1αgene sequences analysis,pathogens were identified were Fusarium oxysporum and F.redolens.Indoor inhibitory activity analysis of eight kinds of fungicides demonstrated that two kinds of fungicides including carbendazim 25%WP and tebuconazole 43%SC had better inhibitory effect on two pathogens.With EC 50 values no more than 0.7 mg/L.Results showed that tebuconazole was the best agent to inhibit the mycelia of the two pathogens,with the EC 50 values were 0.107 mg/L and 0.169 mg/L,respectively.Thus,these two kinds of fungicides can be recommended as alternative agents for field testing.