Vol. 2, Issue 11, Part B (2016)

Abstract
Niger is commonly called “birdseed”. It is important minor, edible, traditional oil seed crop in India. The crop is affected by number of diseases. Among them stem-rot caused by Sclerotium rolfsii., the disease reduces the seed germination and yield up to 40-50%. The present study concentrated on detection, location and seed transmission of S. rolfsii in Niger seeds during kharif seasons-2010-2011. A total of 132 seed samples were collected from farmers, retail shops, fields and APMC markets and were subjected to SBM, PDA, Water agar and 2,4,D methods. Five seed samples showing higher incidence of S. rolfsii and other fungi in SBM were selected for location and transmission of the pathogen. The incidence of ranged between S. rolfsii in selective medium SBM (8-19%). The collected seed samples, fields and farmer’s samples show a higher incidence of S. rolfsii and other fungi. The SBM method is more superior for isolating the S. rolfsii and other fungi than PDA, water agar and 2,4, D methods. The results revealed that the kharif - 2010 shows S. rolfsii (8-19%) in the SBM method. S. rolfsii ranged from (1-6%) in seed coat, (0-2%) in cotyledons, while (0-0%) in embryonic axis. In kharif - 2011, S. rolfsii (11-23%) in the SBM method. S. rolfsii ranged from (3-11%) in seed coat, (3-7%) in cotyledons, while (0-1%) in embryonic axis. The seeds tested during kharif 2010 - 2011 seasons harvested seeds favors the more number of S. rolfsii and other pathogens in the seed coat & cotyledons than in the other components. The transmission of S. rolfsii was (18.0%) in kharif 2010. In kharif 2011, the transmission was (29.4%) in all the five seed samples. The present study reveals that the disease transmission is more during kharif-2011 season than 2010. The S. rolfsii is a causal agent of stem-rot disease of Niger crop.