Assessment of toxicidal and repellency activity of extracts from aerial parts of Prunus laurocerasus for controlling broad mite, Polyphagotarsonemus latus

ABSTRACT Different plant part extracts of cherry laurel [Prunus laurocerasus (Rosaceae)] were investigated for the acaricidal and repellent activity against Polyphagotarsonemus latus (Prostigmata: Tarsonemidae). The leaf, flower, and seed aqueous extracts of cherry laurel were prepared for efficacy bioassays. The tested concentrations of each extract were 1% (volume/volume, v/v), 5% (v/v), 10% (v/v), 20% (v/v) and 30% (weight/volume, w/v). Distilled water and a mixed formulation of 228.6 g/L spiromesifen + 11.4 g/L abamectin   were used as negative and positive controls, respectively. It can be concluded that the flower and leaf extract of P. laurocerasus at 30% concentration and the seed extract at 10% or greater concentrations have the potential to control P. latus in the egg stage. Although spiromesifen+abamectin caused extremely low egg mortality (9.5%), all larvae died shortly after hatching (indirect ovicidal effect). In contrast, all adult mites died within 20 hours after spraying. Moreover, the adult mortalities (92%-98%) associated with seed extract at 30% during the experimental period, and the leaf (93.78%) and flower (91.11%) extract at 30% 72-h after exposure were statistically similar to that of spiromesifen+abamectin (100%) application. All extracts at 20% and seed extract at 10% or greater concentrations may also have a great potential for repelling P. latus.