Deciphering the Synergistic Action of Irradiated Chitosan and Biocontrol Agents for the Management of Powdery Mildew in Grapevines

This study aimed to evaluate the synergistic action of electron beam irradiated chitosan and Ampelomyces quisqualis for the management of powdery mildew, the most significant disease incited by the obligate fungus Erysiphe necator Schw. (Formerly known as Uncinula necator (Schw.) Burr.) that causes substantial losses in grapes. In vivo field trials conducted during 2020-21 and 2021-22, the evaluation of irradiated chitosan and bioagent and fungicide for the efficient in managing the grape powdery mildew disease. The fungicide sulfur 80% WDG was determined to be the most efficient. However, it was followed by a friendly combination of irradiated chitosan (150 ppm) with A. quisqualis (0.5%). Eco-friendly molecules, that is irradiated chitosan 150 ppm with A. quisqualis (0.5%), were found to be the best alternative for chemical molecules to achieve the disease control 63.60% and were identified alternative to chemical treatments to manage the powdery mildew disease of grapes. Irradiated chitosan and biocontrol agents showed synergistic action for the management of powdery mildew in grapevines.