Study of the Effect of Black Leg Disease in Potato Production

The susceptibility of 8 cultivars of potato to infection by black leg disease was studied using artificial inoculation with 10- 4 CFU/ml from isolated bacterial. The results showed that all cultivars were susceptible at different levels, under greenhouse and filed condition. Diamond was found to be the most susceptible cultivar to blackleg disease while Desiree was the least susceptible .Different method to treat the blackleg disease. The symptoms were reduction in the production of tubers and the appearance of infected of leaves and the reduction in different plant heights. The bacteria that cause this disease were isolated from potato tubers, shoots, soil and water. The mother tubers were found to be major source of inoculums for blackleg disease. 4 - 10 .