Biological and Chemical Control of Powdery Mildew (Sphaerotheca pannosa (Wallr.) var. persicae) in Apricot

During the two successive growing seasons 2017 and 2018, powdery mildew (Sphaerotheca pannosa (Wallr.) var. persicae) was recorded on apricot (Prunus armeniaca L.), cv. Canino in four governorates Qaliobia, Menoufia, Beheira and Giza, Beheira governorate recorded the highest percentage in disease incidence followed by Menoufia, Qaliobia and Giza, respectively. The pathogenicity of Sphaerotheca pannosa (Wallr.) var. persicae in inoculated seedlings at 5 days after inoculation confirmed the pathogenicity of the fungus on Amal, Hayed, and El-Amar cvs. The fungicides i.e., Microvit, Topas, Topsin M70, Amistar Top, Bellis and Eminent, as well as the bio-fungicides, AQ10 and Bio Zeid, meanwhile calcium carbonate and sodium bicarbonates were evaluated to control the powdery mildew on apricot in vitro, greenhouse and field conditions. All the tested treatments inhibited conidial germination and the highest efficiency was found for the treatment with Amistar, Bellis and Eminent followed by Topas (100), AQ10 and Bio Zeid, while treatment with Microvit KZ showed lower efficiency. In the greenhouse and under field conditions during the two successive growing seasons 2017 and 2018 at El-Qanater El-Khayria Horticulture Research Station, Agricultural Research Center, Qaliobia governorate, Egypt, to control the powdery mildew (Sphaerotheca pannosa (Wallr.) var. persicae) all the tested fungicides, biofungicides and calcium carbonate and sodium bicarbonates significantly reduced the percentages of disease severity compared with the untreated control. highest efficiency was found for the treatment with Amistar, Bellis and Eminent followed by Topas (100), Topsin M70, AQ10 and Bio Zeid, as well as calcium carbonate and sodium bicarbonates