Publication

Abstract : Black scurf in potatoes is caused by the pathogenic fungus Rhizoctonia (R.) solani, and is a serious disease that results in both quantitative and qualitative losses in potato yields worldwide. To manage this disease in an eco-friendly manner, isotonic aqueous formulation of Chaetomium (C.) globosum was developed and tested for disease control efficacy under both glasshouse and field conditions. A total of 40 fungal isolates was tested in vitro, among which C. globosum Cg-6 exhibited maximum inhibition potential of R. solani (60%) and an increased vigor index (1960.0) in potatoes assessed by the roll towel method. The isotonic solution amended with glycerol supported a maximum fungal population (1.9 × 107 cfu per ml) up to 6 months and retained the most antagonistic activity compared to other preservatives tested (glycine, trehalose, and polyvinylpyrrolidone). Results showed that combined application of C. globosum Cg-6 as a tuber treatment, soil application, and foliar spray effectively reduced the incidence of black scurf (7.6%) and enhanced the germination (94%) of tuber under glasshouse conditions. During field trials, a treatment consisting of C. globosum (TNAU Cg-6; 5 ml per kg of seed), soil application (5 ml per kg of farm-yard manure), and foliar application of 5 ml per litre of water (6 sprays), was shown to reduce black scurf in potatoes and enhanced tuber yield.