Screening of Groundnut Cultivars for Resistance to Collar Rot Caused by Aspergillus niger van Tieghem

Groundnut (Arachis hypogaea L.) is an important legume crop in tropical and subtropical areas of the world. Quantitative and qualitative yield losses result from a number of biotic and abiotic factors that impact groundnut growth and development. Among the fungal diseases, Aspergillus niger van, Teighem causing collar rot of groundnut sometimes referred to as seedling blight is one of the major diseases of groundnut transmitted through soil and seed. The disease has become a serious problem due to its soil and seed borne nature as well as huge economical losses caused by collar rot pathogen. Presently there are many fungicides available that can be used effectively for the management of disease but due to harmful effects of fungicides the use of disease tolerant cultivars is gaining importance in recent years. In this study the disease rating scale given by Mayee and Datar in1986 were used for checking groundnut cultivars reaction. Groundnut yield losses due to collar rot caused by Aspergillus niger are significant. In this study, 30 groundnut genotypes were screened under field conditions over two seasons among these 30 cultivars viz., GJG-32, Girnar-2, Avtar, RG-510, TG-37-A, HNG-10, RG-425 and RG-382 showed moderately resistant reaction, whereas twelve cultivars viz., GJG-11, Kadiri-2 Bold, GJG-19, GG-20, TAG-24, Divya, RG559-3, RG-638, Mallika, KDG-128, RG-578 and Kadiri hatitandra showed moderately susceptible reaction, seven cultivars showed susceptible reaction and three cultivars showed highly susceptible reaction. Out of 30 groundnut cultivars, none of the cultivars showed immune or resistant reaction under field conditions, while eight cultivars showed moderately resistant reaction, twelve cultivars showed moderately susceptible reaction, seven cultivars showed susceptible reaction and three cultivars showed highly susceptible reaction.