Effect of Different Culture Media on Growth and Establishment of Phomopsis vexans Inciting Fruit Rot of Brinjal (Solanum melongena L.)

Abstract

The fruit rot caused by Phomopsis vexans (Sacc. & Syd.) Harter is a destructive disease of brinjal and is considered to be a major constraint for its production. The present study was carried out at the Centre of Excellence for Sanitary and Phytosanitary, Department of Plant Pathology, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, for the evaluation of different culture media on growth and development of Phomopsis vexans. The study showed the maximum radial growth on OMA (90.00 mm), followed by PDA (88.20 mm) and Sabouraud Dextrose Agar (80.16 mm). The pycnidial densities were recorded as excellent on OMA and TFA, good on PDA, SDA, BFA, and MEA, and poor on YMA and CMA media with brown to black colour, while on RSA and WA they were absent. The colony colour were observed on several cultural media with circular and irregular shapes. The maximum pycnidial size was recorded on TFA (454.35×316.18 µm), followed by SDA (415.60× 296.26 µm) and BFA (324.72×368.84 µm), whereas the minimum was recorded on CMA (289.48×128.52 µm), followed by MEA (308.66×140.25 µm). The α-conidia were noticed to be sub-cylindrical and elliptical in shape and largest conidia observed on TMA (10.6×2.6µm), followed by BFA (9.8×2.6µm), and the smallest on RSA (6.1×1.6µm). The number of conidia was recorded highest on OMA (29.) medium and lowest on RSA (12.63). The β-conidia were not observed in this study. The number of guttullae were recorded 1-2 in all tested culture media except TFA and SDA, which had 2-3.