CONTROL OF BACTERIAL LEAF SPOT IN GRAPES

Bacterial Leaf Spot (Xanthomonas campestris) : The disease is more prevalent during June-August and again in February-March. Temperature range O of 25-30 C and relative humidity of 80-90% is favourable for the development of the disease. The young growing shoots are affected first. Disease infects leaves, shoots and berries. The symptoms appear as minute water soaked spots on the lower surface of the leaves along the main and lateral veins. Later on these spots coalesce and form larger patches. Brownish black lesions are formed on the berries, which later become small and shrivelled. Control : Collecting and burning the infected plant parts minimizes the spread of the disease. Streptocycline (500 ppm) is very effective as a prophylactic spray. Weekly sprays of copper fungicide and Bordeaux mixture given from last week of October are effective to prevent the incidence and spread of the disease.