Vol. 11, Issue 11 (2022)

Early blight of tomato is one of the most destructive disease and considered to be great threat to tomato production worldwide. The disease causal organism is Alternaria solani observed in all district of Uttar Pradesh namely Kanpur, Faizabad, Varanasi and Lucknow. Assessment of disease prevalence is an important step as it helps in designing management strategies which ultimately help in increasing the crop yield. Therefore, a roving survey was conducted to find out the disease severity of tomato early blight in aforesaid locations. The disease was prevalent in all the tomato growing areas during rabi 2018-2019. In survey the maximum incidence of Alternaria blight disease was at Prithviganj village of Varanasi in Namdhar-4266 variety. While the lowest incidence of disease was found at Mohanlalganj village of Lucknow in Kashi Vishesh. The isolate from Kanpur (AB1-AB5) showed Light green colony colour, hyphae and septate conidia. The Faizabad isolate AB6 to AB10 showed light green to green colony colour and conidia muriform. The Varanasi isolates AB11-AB15 isolates found dark green colony colour, ovoid to obclavate conidia. The AB16 to AB20 isolates were collected from the region of Lucknow recorded as grey colony colour when colony morphology were analysed with transverse and longitudnal conidia. The collected isolates were checked for colony growth and found >85 mm growth.