MANAGEMENT OF BROWN ROT DISEASE OF POTATO

Abstract

Different applications [various potato cultivars, chemical fertilizers, bioagents and chemical in-ducers] were used for controlling brown rot dis-ease of potato. Potato cultivars namely Diamant, Desiree, Herms, Lady Joy, Lady Rossetta, Nicola, Spunta and Valor were variably susceptible to Ralstonia solanacearum, the causal pathogen of brown rot disease. Herms cultivar was the least susceptible. Application of ammonium sulfate, potassium sulfate, Urea, and calcium superphos-phate to infested soil as a single amendment re-duced disease incidence. Application of calcium superphosphate was the most effective treatment. The bioagents Pseudomonas fluorescens, Pseu-domonas putida and Bacillus subtilis were effec-tive in controlling disease when were used sepa-rately and Pseudomonas putida was the most effi-cient. Foliar spraying with different inducers sin-gly [salicylic acid, di-potassium hydrogen phos-phate and tri-potassium phosphate] reduced the disease incidence. Tri-potassium phosphate was the most effective against the disease. Therefore, a management programme was suggested including cultivar Herms, calcium superphosphate, Pseudo-monas putida and tri-potassium phosphate, as in-tegrated treatment. Rotation of these agents showed high effectiveness to disease control as well on the yield increase.

Keywords

• potato bacterial wilt
• resistance culti-vars
• fertilizers
• biological control
• induced sys-temic resistance