Vol. 8, Special Issue 8, Part O (2024)

Abstract: Sunflower (Helianthus annuus L.) is a crucial edible oilseed crop belonging to the Asteraceae family. It is widely cultivated in the USA, Argentina, France, Spain, China, Ukraine and India. The crop is primarily grown for its edible oil, which has a high concentration of linoleic acid and a moderate level of oleic acid. Despite its expansion in regions such as Punjab, Haryana, Gujarat, Uttar Pradesh, West Bengal, Odisha, Rajasthan and Madhya Pradesh, crop productivity is declining due to various biotic and abiotic stresses. A significant biotic stressor is Alternaria leaf blight caused by Alternariaster helianthi (Hansford) E. G. Simmons, which can result in yield losses of 60-80 percent. The isolation was made from sunflower leaves showing characteristic symptoms of leaf spot. The identification of the pathogen was confirmed based on cultural and morphological characteristics as well as through DNA sequencing. The antifungal activity of seven different natural farming inputs was tested by poisoned food technique under in vitro conditions against Alternariaster helianthi in which cow urine gave better result as compare to other natural farming inputs.