Survey on the Incidence and Severity of Common Scab of Potato in Bangladesh

A survey on the incidence and severity of common scab (Streptomyces sp.) of potato was made in the major potato growing districts of Bangladesh during the cropping season of 2007-2008. A total of 150 fields was surveyed for collection of potato common scab infected samples. It was observed that there was a lot of variation in disease severity and its incidence in different districts of Bangladesh. Highest per cent scab incidence (71.41 %) was recorded in Kahalo Upazila (Bogra) and lowest (13.79 %) in Pirgacha Upazila (Rangpur). Disease incidence also varied among the tested varieties namely, Cardinal, Diamant, Granola, Binella and Raja. Highest incidence was observed in Cardinal (54.08 %) followed by Binella (50.71 %) and it was lowest in Raja (3.07 %). Cardinal and Binella were found to be highly susceptible and Raja was resistant to common scab disease. Diamant, the commercial variety showed medium susceptible reaction to the disease.