Field Trials of Three Fungicides for Controlling Grape Downy Mildew

Effectiveness assessment on three fungicides against grape downy mildew were undertaken. 70%WP propineb and 72% WP mancozeb and cymoxanil mixture had good control effects on grape downy mildew.70% WP propineb diluted 400 to 600 times with water for the second application was also over 79% in effect for 7 days,and over 81% in effect 14 days after the third application.72% WP mancozeb and cymoxanil mixture diluted to 600～800 times was over 65% in effect 7 days after the second applica- tion,and more than 76% in effect 14 days after the third application.35%WP copper hydroxide and cal- cium chloride salt mixture was not favorable in controlling grape downy mildew,control effect being above 59% after three sprays when diluted to 300～500 times.