بررسي اثر برخي عوامل اكولوژيكي در رشد و اسپورزايي قارچ LECANICILLIUM MUSCARIUM روي محيط غذايي جامد

Ecological factors affecting growth and sporulation of Lecanicillium muscarium in solid media.

In this study effect of food quality, light, temperature, relative humidity, pH of medium, alternative food media and physical form of media were investigated on the growth and sporulation of Lecanicillium muscarium (=Verticillium lecanii strain DAOM 198499). Results showed that, the effect of food quality and light on vegetative growth and sporulation was significant (a=0.01). PDA medium with fluorescent light plus 0.5 hour sun UV per day was the best treatment. Effect of food quality and temperature on sporulation was significant (a=0.01) as well. Effect of food quality on vegetative growth was not significant, but the latter was significantly affected by temperature (a=0.01). PDA medium at 22°C was better than the other treatments for sporulation, but this medium at 12°C was the best one for vegetative growth. Effect of pH was significant on sporulation (a=0.01), as well as on vegetative growth (a=0.05). The best treatment was achieved at pH=6 with the average of 4.7x10^7 conidia/ml and 55.66 mm of colony diameter after two weeks. Effect of relative humidity on sporulation was not significant at the range of 70-95%, but the medium was gradually dried up at 60% or lower rate of RH, and thus, the fungal growth was ceased. Effect of physical form of media on sporulation was significant (a=0.01). Potato dextrose as a thin layer was the best treatment with average of 5.02x10^7 conidia/ml. Spore production on alternative solid media was significantly different (a=0.01), and soya with average of 5.73x10^7 conidia/ml showed the highest production rate.