Chemical control of Tetranychus urticae in strawberry crops

The two-spotted spider mite, Tetranychus urticae Koch., is one of the most important pests in strawberry crops and is the main pest in protected environments. To assess the control potential of insecticides/acaricides registered in Brazil, the following control agents, milbemectin, fenpropathrin, pyridaben, abamectin and chlorfenapyr were tested for the control of T. urticaein its different stages (larva, nymph and adult). A preliminary evaluation was carried out just before the first spraying, and evaluations were performed 7 days after the first application (DAA) and at 7, 14 and 21 days after the second application (DAB). The treatments with insecticides/acaricides showed lower numbers of larvae in the evaluations, with chlorfenapyr being the most effective. For the control of nymphs in the comparison between all evaluations, the most effective treatments were Chlorfenapyr and Pyridaben, followed by treatments with Fenpropathrin, Abamectin and Milbemectin. The control of adults was similar among the insecticides/acaricides, but Chlorfenapyr was more efficient, as it acted considerably faster in the control, with an average control of 68.7% followed by Abamectin 61.8%, Pyridaben 60.5%, Fenpropathrin 55.8% and Milbemectin 53.5%. It is concluded that the acaricides reduced the pest infestation, with two sequential applications, being options for integrated management.