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The spider mite Tetranychus urticae, the predatory mite Neoseiulus californicus and the unspecialised feeder Tydeus californicus are frequently encountered on vegetables. The direct and residual effects of six insecticides recommended for the control of aphids, whiteflies and thrips in vegetable crops were evaluated on these mite species in the laboratory. Pesticide effects was often favourable towards T. urticae and unfavourable towards N. californicus and T. californicus. Rotenone was more toxic to eggs than females of T. urticae, and was highly toxic to N. californicus and T. californicus. Pyrethrins and imidacloprid increased T. urticae fecundity but decreased fecundity of N. californicus. Beauveria bassiana was not toxic to T. urticae and T. californicus, but induced high mortality in the progeny of N. californicus. Azadirachtin and pymetrozine were the least toxic to T. urticae and N. californicus, but affected T. californicus progeny. Implications of this study for IPM tactics are discussed

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Molecular approaches are increasingly used to help in species diagnostics. These approaches have been recently and successfully applied to assess some taxonomic questions within the mite family Phytoseiidae. However, many protocols for DNA extraction of such small specimens require crushing the entire sample, precluding deposition of the carcass as a museum voucher. This study aimed to determine the efficiency of a modified Qiagen DNeasy tissue kit extraction method to both extract enough DNA for performing PCR and DNA sequencing, and recover intact the adult female specimens for identification. Two types of biological material were studied for two species: 100 % alcohol preserved females and females mounted in lactic acid for four hours. All specimens were retrieved after DNA extraction and were mounted on slides. All the structures used for species identification were visible with a phase microscope. DNA was successfully extracted from all the specimens considered and fragments of CytB mtDNA of 426 bp were amplified and corresponded to those of the two species considered. The Qiagen DNeasy tissue kit extraction protocol thus permits to retrieve, prepare and identify mites for which DNA has been successfully extracted, whatever the material considered: alcohol preserved or lactic acid treated mites. This result is of major interest for future taxonomic studies of the family Phytoseiidae, as it will allow the assignment of morphological and molecular attributes to a same specimen.