Among the diseases affecting Sesame, root rot caused by Macrophomina phaseolina is the most serious one. The incidence of this disease creates havoc in greater magnitude that the farmers are inclined to think about the cultivation of other crops in place of sesame. To assess the extent of damage caused by root rot disease in Cuddalore and Ariyalur districts of Tamil Nadu. The survey revealed the endemic nature of the root rot disease. Among the different locations, Srimushnam (MP6) registered the maximum incidence of the disease (42%) followed by Karmankudi (MP2) with 40%. The isolates collected from different locations showed varied levels of pathogenicity. All the fifteen isolates of the root rot pathogen M. phaseolina showed variations with regard to mycelia growth, sclerotial size and production. The isolate (MP6) collected from Srimushnam was found to be more virulent as evidenced with higher disease incidence.
Macrophomina paseolina, Pathogenicity, Virulence
