Improvement of biocontrol programs with releases of astigmatid mites as in-crop food for phytoseiids, mirids and anthocorids

Abstract: The use of supplementary foods to encourage the early establishment and
conservation of natural enemies in periods of prey scarcity is a strategy widely implemented in augmentative biocontrol programs. Several commercial factitious foods are introduced into different protected crops. In a previous study, we developed a program to control thrips on chrysanthemums and cucumbers based on the introduction of astigmatids as food for predatory mites. A similar strategy allowed a preventive control of Aculops lycopersici with Transeius montdorensis on tomato. In this study, novel mixed diets have been designed considering the nutritional requirements of each predator and the nutritive profile of different factitious prey. A mixed diet composed of astigmatid mites, Artemia cysts and Sitotroga cerealella eggs has allowed to increase the populations of Orius laevigatus and Macrolophus pygmaeus on chrysanthemum and tomato crops, respectively, when compared with other foods used by growers. The replacement of S. cerealella eggs with nematodes (Panagrolaimus species) improves the establishment of a new selected strain of O. laevigatus (Oricontrol PLUS®) in chrysanthemum crops. Similar results using this new nematode-based diet have been achieved for other predators on other crops. The use of this diet as supplementary food for mirids, anthocorids and phytoseiids is discussed.