EFFECT OF MEDIA, NITROGEN SOURCES AND TEMPERATURE ON THE GROWTH AND SPORULATION OF CURVULARIA LUNATA CAUSING CURVULARIA LEAF SPOT OF BLACKGRAM

Abstract

Curvularia leaf spot of Blackgram is an important disease in the class of fungal diseases of black gram. The effects of different media, nitrogen (N) sources and temperatures on Curvularia lunata causing curvularia leaf spot of Blackgram, were examined to determine optimal conditions for mycelial growth and sporulation. In vitro studies were carried out to select the suitable media for proper growth and sporulation using both solid and liquid media. Amongst solid media, Potato dextrose agar (7.60 cm) and Host extract agar (6.73 cm) were the best for fungus growth as well as for sporulation followed by Conn’s agar and Czapek (Dox) agar. Whereas in liquid media, Richard’s (834.33mg), Czapek (Dox) (830.00mg), supported best growth of the fungus and same composition of media were also suitable for the sporulation. Different sources of nitrogen were evaluated for exploring suitable sources of nitrogen for growth and sporulation. It was observed that potassium nitrate (435.00mg) was the best source of nitrogen for the growth of the fungus followed by urea (371.33mg) and calcium nitrate (360.00mg). Different temperatures (8, 15,20,25,28 30 35 and 37°C) were tested for suitable fungal growth and it was observed that fungus can grow up to temperature range of 15°-37°C. Whereas 28°C (830.00 mg) were the optimum for the growth of the fungus followed by 300C (734.66 mg). Identified suitable media could be used for growth and sporulation study and temperature ranged could be used for epidemiological study.