王大会 蒋承耿 王忠宇 龙友华 樊荣 莫飞旭 石金巧

摘 要：为明确在贵州省六盘水市烟区发生的一種烟草细菌性叶枯病的病原并筛选出防治药剂，本研究通过组织分离法分离病原菌，结合形态学鉴定、柯赫氏法则和分子生物学等方法鉴定病原菌，并初步研究该菌的生理生化特性，采用抑菌圈法测定15种杀菌剂对该病原菌的毒力。结果表明，该病害病原菌与成团泛菌（Pantoea agglomerans）同源性达100%，为革兰氏阴性菌，可利用D-阿拉伯糖、丙三醇和硝酸盐等碳氮源;室内防治药剂筛选试验表明，1.6%噻霉酮EW、3%中生菌素WP和80%乙蒜素EC对该菌有较好的抑菌效果，EC50值分别为0.004、0.0135和0.1176 mg/mL。试验表明，该烟草细菌性叶枯病致病菌为成团泛菌（Pantoea agglomerans），1.6%噻霉酮EW可作为防治该病害的有效药剂。

关键词：烟草;叶枯病;成团泛菌;病原鉴定;药剂筛选

Abstract： In order to identify the pathogen of bacterial leaf blight in Liupanshui City， Guizhou Province and screen for control agents， in this study pathogenic bacteria were isolated by tissue separation. In combination with morphological identification， Koch's rule and molecular biology approaches， physiological and biochemical characteristics of the bacteria were preliminarily studied. The toxicity of 15 fungicides to the pathogen was determined by the bacteriostasis method. The results showed that the pathogen has 100% homologous with Pantoea agglomerans， a gram-negative bacterium， which can use carbon and nitrogen sources such as D- arabinose， propanol and peptone. The screening test of indoor control agents showed that 1.6% Thiamphenone EW， 3% Zhongshengmycin WP and 80% Ethylicin EC had good antibacterial effects on the bacteria. The EC50 values were 0.004 mg/mL， 0.0135 mg/mL and 0.1176 mg/mL respectively. The tests showed that the bacterial leaf blight pathogen of tobacco was Pantoea agglomerans. 1.6% thiamethoxone EW can be used as an effective agent to control the disease.

Keywords： tobacco; leaf blight; pantoea agglomerans; pathogen identification; pesticide screening

烟草（Nicotiana tabacum L.）是我国重要的经济作物之一[1-2]，烟草病害是制约烟草生产的重要因素。目前已报道的烟草侵染性病害有60余种[3]，其中常见的叶部病害包括由毁灭炭疽菌（Colletotrichum destructivum）、链格孢菌[Alter aria alternata （Fries）]、二孢白粉菌（Erysiphe cichoracearum）]等真菌引起的烟叶炭疽病、赤星病、白粉病等[4-6]，由烟草假单胞杆菌（Pseudomonas syringae pv. Tabaci）、丁香假单胞杆菌角斑专化型[Pseudomonas syringae pv.Angulata （Fromeetal） Holland]、青枯雷尔氏杆菌（Rastonia solanacearum）等细菌引起的野火病、角斑病及青枯病等[7-9]，以及由TMV、CMV、PVY等引起的烟草病毒病[10]。与之前报道的所有病害均不相同，2011年在贵州省六盘水市保田镇烟区零星发生一种烟草叶部病害，可引起烟株中下部叶片腐烂，通过室内保温保湿培养可观察到病部产生菌脓，因此初步判断该病害为细菌性病害。……