设施蔬菜苗期病害病原鉴定及化学药剂筛选

Identification of Seedling Disease Pathogens in Greenhouse Vegetable and Screen of Fungicides

采用普查和定时系统调查的方法对十字花科（大白菜、青花菜、甘蓝、萝卜）、茄科（番茄、辣椒、茄子）、葫芦科（黄瓜、冬瓜、南瓜）等10种主要设施蔬菜苗期病害种类进行了调查,在此基础上采用形态学和分子生物学方法对病原进行鉴定,并对疫病、猝倒病、枯萎病、立枯病等4种主要苗期病害进行化学防治药剂筛选。结果表明：从10种蔬菜上采集的864份苗期病害病样中共分离出736株菌株,共计16个种,其中致病病原有13种,在各类蔬菜上可分别引起8~9种苗期病害,以传统病害猝倒病和立枯病为主,其次为根腐病、疫病、灰霉病;筛选出对立枯病防效显著的杀菌剂32.5%苯甲·嘧菌酯悬浮剂和2.5%咯菌腈悬浮剂,对防治枯萎病有效的药剂70%甲基托布津可湿性粉剂、36%甲基硫菌灵悬浮剂和3%甲霜·噁霉灵水剂,对疫病防效显著的药剂68%精甲霜·锰锌水分散粒剂、25%甲霜·霜霉威可湿性粉剂、72%霜脲·锰锌可湿性粉剂、50%烯酰吗啉水分散粒剂、50%氟啶胺悬浮剂、64%噁霜·锰锌可湿性粉剂、10%氰霜唑悬浮剂,以及防治猝倒病有效的药剂50%氟啶胺悬浮剂、64%噁霜·锰锌可湿性粉剂、10%氰霜唑悬浮剂、72%霜脲·锰锌可湿性粉剂、72.2%霜霉威盐酸盐水剂、50%烯酰吗啉水分散粒剂、68%精甲霜·锰锌水分散粒剂和60%唑醚·代森联水分散粒剂等。

Major seedling diseases of 10 vegetable species in greenhouse, including Cruciferae （ Chinese cabbage, broccoli, cabbage, radish ）, Solanaceae （ tomato, pepper, eggplant ） and Cucurbitaceae （ cucumber, wax gourd, pumpkin ） were investigated and their pathogens were identified according to their morphological characteristics and molecular biology. The control effect of fungicides collected from different sources and against 4 main seedling diseases including damping-off, rhizoctonia disease, Fusarium wilt disease and Phytophthora blight were screened. The results showed that 736 bacteria strains were isolated from 864 seedling disease samples of 10 vegetable species. And 16 isolates were identified, among them 13 infective pathogens could generate 8-9 types of seedling diseases in various vegetable species. The most prevalent seedling diseases were traditional damping-off and rhizoctonia diseases, followed by root rot, Phytophthora blight and gray mold. The effective fungicides were screened out. 32.5% Difenoconazole ·azoxystrobin suspension concentrate （SC） and 2.5% fludioxonil SC had remarkable effect in controlling rhizoctonia disease. 70% thiophanate methyl wettable powder （WP）, 36% Thiophanate-Methyl SC and 3% metalaxyl · hymexazol aqueous solutions （AS） were effective for controlling Fusarium wilt. 68% metalaxyl-M mancozeb water dispersible granule （WG）, 25% metalaxyl-propamocarb WP, 72% cymoxanil · mancozeb WP, 50% dimethomorph WG, 50%Fluazinam SC, 64% oxadixyl · mancozeb WP and 10% cyazofamid SC had outstanding effect in controlling Phytophthora blight, 50% Fluazinam SC and 64% oxadixyl · mancozeb WP, 10% cyazofamid SC, 72% cymoxanil · mancozeb, propamocarb hydrochloride WP, 72.2% Propamocarb hydrochloride AS, 50% dimethomorph WG, 68% Metalaxyl-M mancozeb WG and 60% pyraclostrobin＋metiram WG etc.were effective for controlling damping-off.