辣椒白绢病菌的生物学特性及其防治效果

Study on biological characteristics and the chemical control effect of pepper southern blight pathogen Sclerotium rolfsii Sacc.

经调查鉴定辣椒白绢病由齐整小核菌Sclerotium rolfsiiSate．引起；对分离纯化的病菌进行了生物学特性研究。结果表明，30℃、pH值5．0～6．0条件下适宜菌丝生长；25～35℃、pH值4．0～6．0、光照、相对温度100％加水等奈件适合菌核萌发。室内毒力测定试验显示，药荆浓度为100～300μg／mL时，3％广枯灵水荆的抑菌率均为90％以上，75％百菌清WP、50％多菌灵WP和70％甲基硫菌灵WP的抑菌率在300μg／mL时仅为70％左右；田间防治试验中，3％广枯灵水剂、3％广枯灵水剂＋抗病丰（6％抗坏血酸水剂）对辣椒白绢病的防治效果较好，均在85％以上，明显优于其他供试药剂。其中3％广枯灵水剂＋抗病丰（6％抗坏血酸水剂）的防治效果最好，且发病植株生长恢复较快，有利于提高发病辣椒的产量和质量。

The biological characteristics of pepper southern blight pathogen Sclerotium rolfsii Sacc. were studied. The results show that hypha could grow when cultured at temperature 30℃, pH 5.0 - 6.0. Conditions such as temperature 25 -35℃, pH 4.0 -6.0 ,light, 100 relative humidity and added water were beneficial to sclerotial germination. The toxicity test in labs showed that the inhibition rate of Guangkuling 3% AS to pepper southern blight pathogen was above 90% at 100 - 300μg/mL,but the inhibition rates were only about 70% when treated with Chlorothaloni175% WP, Carbendazim 50% WP and Thiophanate methyl 70% WP at 300μg/mL. The control experiment in fields showed that the control effects of Guangkuling 3% AS,Guangkuling 3% AS with 6% Ascorbic acid WA on pepper southern blight were above 85% ,obviously better than other chemicals. The control effect of Guangkuling 3% AS with 6% Ascorbic acid WA was the best. It could make the infected plants recover quickly and improve the yield and quality.