STUDIES ON SOME PHYSIOL(x;ICAL ASPECTS OF Phomopsis vexans CAUSING PHOMOPSIS BLIGHT AND FRUIT ROT OF EGGPLANT

Abstract

The effect of temperature. light, culture media and pH on the mycelial growth and sporulation behaviours of Phomopsis vexans, causal organism of Phomopsis blight and fruit rot of eggplant were studied in the laboratory. The pathogen grew best at 25°C, under 12112h cycle light and pH 5.5 levels of culture media. Number of spores per millilitre was also maximum at 25°C temperature, 12112h cycle light and at pH 5.5. Eggplant Fruit Extract Agar media gave the maximum growth and sporulation of P. vexans. Two types of conidia, u (alpha) and [l (beta) were detected in P. vexons. Five groups of isolates showed variation in growth and sporulation under different levels of temperature, light, culture media and pH. Alpha and beta conidia varied in size for live isolates groups. Existence of variation in isolates of P. vexans revealed the existence of the variability of P. vexons occurs in Bangladesh.