巴宜区玉米细菌性顶腐病发生规律及病原菌分离

Occurrence and Pathogen Isolation of Maize Bacterial Top Rot in Bayi District

近年来,西藏林芝市巴宜区初现玉米细菌性顶腐病。通过对该病进行症状观察和发生规律的定点、定期调查,发现引起该病的病原菌喜温喜湿,在玉米抽雄期发病率达到顶峰。对病株的根际土壤和发病部位叶片分别进行病原菌的分离和纯化,从土壤中共分离到12个菌株,从叶片中共分离到17个菌株,对分离到的菌株进行形态去重复和革兰氏染色,得到可能引起玉米细菌性顶腐病的6株革兰氏阴性菌:YMY3-4,YMY3-11,YMY4-2,YMY4-4,YMY4-5,YMY4-6。本试验为进一步开展该病的致病性测定,确定病原菌,为该病害的防治奠定理论基础。

In recent years,bacterial top rot of maize was firstly reported in Bayi District,Nyingchi,Tibet.Through fixed-point and regular surveys on the symptoms and occurrence pattern of the disease,the results showed that the pathogen of this disease prefered temperature and humidity,and the incidence reached the peak at the stage of maize male-drawing.A total of 17 strains were isolated from the leaves and 12 strains were isolated from the rhizosphere soil of the diseased plant.The morphological characteristics of the isolated strains were treated by de-duplication and Gram staining,and 6 Gram-negative strains were isolated,YMY3-4,YMY3-11,YMY4-2,YMY4-4,YMY4-5,YMY4-6.The study laid a theoretical foundation for further pathogenicity inoculation test,pathogen identification and disease control technology.