Abstract

PATHOPHYSIOLOGICAL VARIATIONS AMONG ISOLATES OF COLLETOTRICHUM TRUNCATUM CAUSATIVE AGENT OF ANTHRACNOSE OF TOMATO

Indrajeet Ashok Samant* and Yogesh Suresh Andoji

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Abstract

Tomato is an important vegetable crop worldwide and one of the most important vegetables in India. Andhra Pradesh, Karnataka, Maharashtra, Orissa, West Bengal, Tamil Nadu, Madhya Pradesh, Gujarat, Assam, Rajasthan and Punjab are found to be important states growing Tomato in India. Anthracnose caused by Colletotrichum truncatum is a major problem in India and one of the more significant economic constraints of Tomato production worldwide, especially in tropical and subtropical regions. Three isolates of C.truncatum were collected from different Tomato growing areas of Sangli District and their pathogenicity was proved under laboratory conditions. Effect of different pH levels, temperature, light intensity and seed quality tested against the growth of C. truncatum under in vitro. Results indicated that the growth of C. truncatum was maximum at pH range of 6.50-7.00 and temperature range of 25-30°C. Exposure of the fungus to alternate cycles of 12 hr light and 12 hr darkness resulted in the maximum mycelia growth of C. truncatum compared to the 24 hr exposure to either continuous light or dark. Potato dextrose agar medium supported significantly the maximum growth of all the three isolates of C. truncatum. Further, the strains were found to vary morphologically between the isolates under the study.

Keywords: Tomato, Anthracnose, pathogenicity test, seed quality test, temperature, pH and light intensity.