B.MishraBasanti Oraon2024-06-212024-06-211996https://krishikosh.egranth.ac.in/handle/1/5810210720Soybean (Glycine max (L.) Morril) suffers from leaf spot disease caused by Cercospora sojina. The characteristic symptom was observed on leaf, atom, petioles and pads as also in seeds. The pathogen has been described in detail which appears to be a now host record in the plateau region of Bihar. It causes on appreciable damage (incidence 4.96-9.67 per cent) and severity (12.0 to 38.50 per cent) in and around Ranchi. In cultural studies, the radial growth and sporulation was best in Potato dextrose agar as well in Potato dextrose broth. However, the later gave excellent sporulation. The growth and sporulation were maximum at 28.1°C and pit 6.0 and thus were optimum temperature and pit, respectively. Glucose and Calcium nitrate were best sources of carbon and Nitrogen, respectively for maximum growth and sporulation. The diseased plant debris and diseased seed cause 16-65 per cent infection in the crop. The diseases was more severe with the environmental variables viz; reinfell (18.6 mm), relative humidity (71.7 %) and temperature (23.7°c) in Kanke conditions. In management trials, Drago variety of soybean proved to be moderately resistant against the pathogen. The pathogen could be effectively controlled with savistin (0.05 per cent) and Captor (0.2 per cent). In bio control, leaf extract of Argemon maxicana (20 per cent) inhibited maximum growth and sporulation of the pathogen.EnglishThesis