Effects of acaricides on Oligonychus sp. and compatibility with predatory mites Neoseiulus californicus and Phytoseiulus persimilis

In Mexico, outbreaks of phytophagous papaya mites (Oligonychus sp.) can threaten papaya production by damaging young leaves, causing a reduction in plant vigour and fruit yield. In the present study, we evaluated the effect of conventional acaricides on the papaya mite and on predatory mites Neoseiulus californicus and Phytoseiulus persimilis. In the laboratory, residual toxicity was tested by exposing Oligonychus sp. to acaricide-immersed leaves and the predatory mites to acaricide-coated glass vials. In the greenhouse and small field plots, mite-infested papaya leaves were sprayed with different acaricides to evaluate their control of Oligonychus sp. In the laboratory, abamectin, spirodiclofen, and fenpyroximate caused the highest mortality (95–100%) of Oligonychus sp. adults and nymphs on day 1 after application. These acaricides also caused 100% adult mortality of both predatory mites. Spirodiclofen and etoxazole killed all eggs of Oligonychus sp. In the greenhouse and small field plots, abamectin, spirodiclofen, and fenpyroximate were effective at controlling the population of adults, nymphs, and eggs of Oligonychus sp.