بررسی اتیولوژی و دامنه انتشار شانکرباکتریایی در باغات کیوی

In order to investigating of kiwifruit bacterial canker,a survey was conducted during 1380-3 in west of Mazandaran.According to symptoms,sampling were done from flower,twigs and trunk of kiwifruit vines.These disinfected by ethylic alcohol 70% ,then washed by distilled water and cultured on king B medium.The colonies with fleorecent pigment were selected and purofied on nutreint agar medium.All isolates had positive hypersensitive reaction on tobacco. They produced levan from sucrose and did not rot potato tuber slices.Oxidase and Arginine dehydrolase tests of isolates were negative. According to LOPAT test,isolates were identified as a Pseudomonas syringae. Most of isolates were pathogenic on kiwifruit seedlings in greenhouse and produced necrotic spots on leaves in lab condition.Some of isolates were not pathogenic and there are epiphytic.Therefore,the agent of bacterial canker of kiwifruit in Iran is Pseudomonas syringae pv.syringe. Pseudomonas syringae. also was isolated from some annual plants and trees but it was not pathogenic,eXeption citrus and peach isolates.The resultS showed,the distribution of infection is arregular in kiwifruit cultivating areas in north of Iran.As well as severity of infection has direct relation with rainfall in spring and cold in winter.