Non-target effects of pesticides on key predators in -greenhouse integrated pest management systems

The most common method of controlling pests and diseases in agriculture is through pesticide applications, though these are known to be harmful to humans, animals, and the environment. Biological pest control and selective insecticides are more compatible with the basic principles of integrated pest management practices. In this context, we evaluated eight plant protection products, including insecticides and fungicides, against two predators, Orius laevigatus and Amblyseius swirskii, using International Organization of Biological Control (IOBC) guidelines. These two predators are key natural enemies of several agricultural pests of greenhouse and open production systems, particularly thrips and mites. Abamectin and dimethoate were ranked as harmful to both predators and spinosad to A. swirskii. Emamectin benzoate and the fungicide kresoxim-methyl + boscalid were moderately harmful, causing 31% to 73% mortality in A. swirskii and O. laevigatus. The insect growth regulator pyriproxyfen and fungicides cymoxanil+propineb and copper oxychloride were determined harmless to both A. swirskii and O. laevigatus, causing <30% mortality. Additional testing of these products is warranted to determine their effects on natural enemies in glasshouses or open fields. We expect the severity of the products' effects to be reduced, given environmental factors that affect their efficacy and the protection afforded by plant architecture to predators.