Management Powdery Mildew of Marigold (Calendula Officinalis) Using some Nanoparticles and Chitosan

Abstract

The effect of seven substances, Copper, CuO, ZnO, AlO NPs (8 mg L−1), CuO, ZnO, AlO (8 mg L−1) and chitosan was evaluated under both greenhouse and field conditions during two growing seasons (2017/2018 and 2018/2019) to control powdery mildew disease caused by Erysiphe cichoracearum on marigold (Calendula officinalis). Results have shown that all the treatments tested had decreased disease severity compared to the non-treated control. In this respect, chitosan showed the best effect in decreasing disease severity followed by ZnO NPs. Meanwhile, CuO gave the lowest effect in this respect. The decrease in disease severity of powdery mildew was positively expressed by an increase in crop parameters, i.e. numbers of inflorescence weight, fresh and dry weights of plants, plant height, number of branches and increased chlorophyll ( a and b) and carotenoids.