Abstract:

Cotton (Gossypium hirsutum L.) is one of the most important fiber crops playing a key role in the economic and social scenario of the globe. India is one of the major cotton-growing countries in the world. India ranks first in area and second in the total production of cotton in the world. Cotton is grown worldwide for its natural fiber and oil. As cotton seed contains 30 per-cent starch, 25 per-cent oil and 16.20 per-cent protein. Looking to the overall situation, it is felt necessary further to investigate its potential in terms of morphology and cultural characteristics. In this experiment, the effect of different temperaturer on morphological and cultural characteristics of the Corynespora cassiicola pathogen was studied in cotton. The result showed that at 30°C temperature, there was the maximum dry mycelium weight (60.33mg) and abundant (++++) sporulation was noticed. The size of conidia was maximum at 30°C (126.00 × 8.30µm) followed by 25°C (118.23 × 7.82µm) was recorded. The cultural studies of C. cassiicolawas made by growing single spore cultures on PDA medium at various temperatures in vitro yielded the largest colony diameter (90.00mm) at 30°C temperature.