A phytoseiid predator from the tropics as potential biological control agent for the spider mite Tetranychus urticae Koch (Acari: Tetranychidae)

The two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) is one of the most important pests of many crops in temperate and tropical climates. Chemical control is the main method of combating this mite, but it is less preferred due to the development of resistance as well as environmental problems associated with the use of pesticides. Biological control of spider mites has been tried as a logical alternative method for chemical control. Studies have been conducted in different countries to assess the effect and potential of natural enemies for controlling the pest. The predatory mite Phytoseiulus macropilis (Banks) (Acari: Phytoseiidae) was found associated with spider mites in strawberry crops in the state of Minas Gerais, Brazil. Earlier studies suggested that P. macropilis was able to control spider mites, but predation and oviposition rates have not been measured so far. We measured predation and oviposition on strawberry with spider mites as prey in the laboratory. The predator fed on all prey stages and showed capacity to control local prey populations on leaf disks. The oviposition rate of P. macropilis is similar of the most used predatory mite Phytoseilus persimilis and the predation rate is higher than that of the latter. Our results suggest that P. macropilis is a promising candidate to control two-spotted spider mites in the tropics and other areas. (c) 2007 Elsevier Inc. All rights reserved.