Control efficacy of 56% cupric hydroxide·dimethomorph WP against phytophthora blight in pepper plants

The control efficacy of 56% cupric hydroxide·dimethomorph wettable powde(WP) against phytophthora blight in pepper plants was studied by pot test and field trials.The resuls of pot test indicated that the protective efficacy was 83.66% to 88.09% after 4 days to 6 days when the pepper seedlings were treated by the fungicide 93.3 μg·mL~(-1),while the remedial efficacy was(81.31%) to 83.77% after 4 days to 5 days the diseased seedlings treated by the fungicide 186.6 μg·mL~(-1).The protective mass of efficacious ingredients was only half of the remedial mass.The field efficacy trials showed that the relative control efficacy was more than 90.32% when the pepper plants were treated by the fungicide twice at the concentration 280.0 μg·mL~(-1)in the growth period;while it was more than 75% when the pepper fruits were treated once at the same concentration.The fungicide didn′t show any phytotoxicity on pepper plants at used concentration.