Using posibilities of combinations of Orius laevigatus, Amblyseius swirskii and Neoseiulus cucumeris against frankliniella occidentalis in sweet pepper greenhouse

In this study, the effectiveness of predatory mites Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae), Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) and predatory bug Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) was evaluated individually and in a combination to control Western flower thrips [Frankliniella occidentalis (Pergande) (Thysoneptera: Thripidae)] which causes important damages on greenhouse sweet pepper production in Turkey. The study was carried out in a 1000 m² greenhouse which located in Antalya-Aksu (Kursunlu village, Yorukler district) in 2016 and 2017. The untreated, individual O. laevigatus application, individual A. swirskii application, individual N. cucumeris application, the combination release of O. laevigatus and A. swirskii, the combination release O. laevigatus and N. cucumeris and the standard insecticide applied plots were the treatments of the trials. The treatments were applied in a completely randomized block design in three replications and each plot consisted of 25 m² /150 plants. In the result of both first and second experiments, the highest efficacy was observed in the treatment which O. laevigatus and A. swirskii were applied in a combination; the lowest efficacy was observed in the untreated plots. The combination of O. laevigatus and A. swirskii were found more effective than the plots that the predators were applied individually. The enough efficacy was not observed on leaves while the thrips population were controlled in flowers, in the plots where O. laevigatus applied individually. In the plots that A. swirskii was individually applied, thrips population was controlled on leaves, but could not be controlled in the flowers in both years. In individually N. cucumeris applied plots, limited control was observed on the leaves however the thrips population could not be controlled in the flowers; additionally, it was observed that it was less effective and significantly different from individually A. swirskii applied plots. Standard insecticide applied plots were less effective than O. laevigatus and A. swirskii combination.