The toxic effects of some acaricides on the tomato russet mite and its predator Amblyseius swirskii Athias-Henriot, 1962 (Acari: Phytoseiidae)

The tomato russet mite, Aculops lycopersici (Massee, 1937) (Acari: Eriophyidae) is a common pest of tomatoes. The predatory mite, Amblyseius swirskii Athias-Henriot, 1962 (Acari: Phytoseiidae), can control A. lycopersici populations. To integrate biological and chemical control of A. lycopersici, side effects of the lethal concentrations of acaricides, as a predator, on A. swirskii should be considered. The lethal concentrations of 14 acaricides for A. lycopersici were determined under laboratory conditions at Bursa Uludağ University during 2017-2018. To understand the toxic impacts of the acaricides on juveniles and females of A. swirskii, the LC99 values for A. lycopersici of each acaricide were applied to A. swirskii. The reproduction reduction effects of the LC99 values were also assessed. Quite low concentrations of abamectin, milbemectin, pyridaben, azadirachtin and sulphur were found to be toxic for A. lycopersici. Based on the side effect scale, the LC99 values of abamectin, acequinocyl, bifenazate, fenproximate, fenbutatin oxide, hexythiazox, milbemectin and sulphur that killed A. lycopersici were found to be slightly toxic to both females and juveniles of A. swirskii. The results of this comparative toxicological study have showed that more field studies should be conducted to evaluate the effectiveness of using low concentrations of acaricides with A. swirskii in combination for controlling A. lycopersici.