一种由山葵果胶杆菌引起的马铃薯细菌性软腐病

Bacterial Soft Rot Disease of Solanum tuberosum L. by Pectobacterium wasabiae

【目的】本文确定了引发青海省马铃薯(Solanum tuberosum L.)细菌性软腐病的病原。【方法】结合选择性CVP培养基上菌落形态观察、致病性测定、16S r DNA序列以及Pectobacterium spp.的序列特征分析,对从青海大通县马铃薯软腐病样中的病原菌进行生物学鉴定。【结果】鉴定出肠杆菌科果胶杆菌属山葵果胶杆菌(Pectobacterium wasabiae)能引起青海马铃薯细菌性软腐病。生理生化试验表明,该病原菌株不能在37℃生长,能使明胶液化,不具有耐盐性,对红霉素不敏感;过氧化氢酶反应为阳性,氧化酶、蔗糖试验还原反应、吲哚产生和磷酸酶活性试验均为阴性;可以利用纤维二糖和柠檬酸盐,不能利用D-麦芽糖、山梨醇、D-阿拉伯糖、α-甲基葡萄糖、乳糖、棉子糖和蜜二糖。【结论】研究结果可为青海马铃薯软腐病的综合防治提供科学依据。

【Objective】This present study aimed to identify the causal pathogen causing soft rot of potato（ Solanum tuberosum L.） in Qinghai province.【Method】One strain isolated from infected potato tubers was characterized by morphology on CVP medium,pathogenicity test,analyses of 16 S rRNA sequence as well as Pectobacterium spp. sequence characteristics.【Result】This strain was identified as Pectobacterium wasabiae and belonged to Enterobacteriaceae,Pectobacterium. The physiological and biochemical tests showed that the bacterium could not grow at 37 ℃,caused gelatin liquefaction,had not the tolerance to salt in 5 % Na Cl solution and had no sensitivity to erythromycin; The bacterium gave a positive response to catalase but negative responses to oxidase,phosphatase activity,indole production and sucrose reduction reaction. The bacterium utilized some substances including citrate and cellobiose but could not utilize D-maltose,D-sorbitol,D-arabitol,α-methy lglucoside,lactose,raffinose,and melibiose.【Conclusion】These results would provide a scientific basis for the integrated control of potato soft rot disease.