Using greenhouse microclimate to improve the efficacy of insecticide application for Frankliniella occidentalis (Thysanoptera: Thripidae)

Abstract

The effectiveness of insecticide applications for control of Frankliniella occidentalis (Pergande) was improved by manipulating greenhouse microclimate conditions. Trials were conducted under controlled environment chamber and greenhouse conditions. Temperature and vapor pressure deficit (VPD) had significant effects on the flight activity of thrips in Plexiglas boxes in controlled environment chambers. On the plant surface in the greenhouse; however, temperature played the more dominant role. Raising the greenhouse air temperature from 21-23 to 26-28°C resulted in increased flight activity and improved mortality from insecticide (endosulfan) application by 23-2.5%. Based on the flight activity under laboratory conditions, a quadratic model was developed. This model can be used to predict the flight activity of thrips under combinations of temperature and VPD that can occur during greenhouse crop production.