BACTERIAL SOFT ROT OF POTATO AND ITS CONTROL

Abstract

Survey carried under two different storing condition, showed that the incidence and severity of soft rot of potatoes were very high in none-cooled stores with the values of 28.92% and 0.11 respectively while the lowest was in cold storage with values 20.94% and 0.07 respectively. The following treatments were used in this study to control the disease: 1×10 4 cell/ml of Bacillus subtills, 10gm/kg of Halex 5ml/L of ciprofloxacin, 1ml/L of Bettanol, and 4% sodiume hypochlorate. All the above treatment lead to reduce the rate and the severity of the disease and to reduce the effect of the Erwinia carotovora on the stem high, dry weight of foliage and total weight of tubers per plant . the treatment with biological fertilizer (Halex) exceeded all the others in field and green house experiments . Reducing the rate and severity of soft rot disease in the storage foliage was cut before harvesting and when was near to mature, in two different dates (two and four days) after the last irrigation of the field. Harvesting the tubers after eight days after last irrigation from cutting the foliage led to reduce the rate and severity of soft rot of the tubers and severity of soft rot of the tubers in the cooled storage, with the values of 15.62% and 0.13, respectively. Curing of tubers after harvesting and before interning to the storage was achieved by leaving them in shadow for two or four days. The rate and the severity of tubers soft rot in the cooled storage with the values of 9.76% and 0.08, respectively.