Nutritional and Physiological Requirement of Alternaria brassicae, Causing Alternaria Leaf Spot of Cauliflower

Alternaria leaf spot caused by Alternaria brassicae (Berk.) Sacc. is one of the most destructive disease of cauliflower (Brassica oleracea var. botrytis.), causing accountable losses of about 20 to 80 per cent. Present investigations were carried out to assess the effects of carbon and nitrogen sources and temperature on growth and sporulation of A. brassicae. The study was undertaken during 2013–14 at the Department of Plant Pathology, College of Agriculture, Parbhani. Results revealed that of the six carbon sources tested, Maltose encouraged significantly highest mean mycelial growth (90.00 mm), followed by Glucose (84.23 mm) and Starch (81.22 mm), rest of the carbon sources are in the range of 78.20 (Sucrose) to 44.67 (Galactose) and among nitrogen sources tested, Potassium nitrate was found better with significantly highest mean mycelial growth (87.67 mm), followed by Sodium nitrate (72.87 mm) and Calcium nitrate (59.62 mm), rest of the nitrogen sources are in the range of 54.80 (Peptone) to 9.19 (Thiourea), Whereas, of the temperature regime tested significantly highest mean mycelial growth was recorded on 25 ^C (90.00 mm), followed by 30°C (88.12) and 20°C (67.05).