Phototactic behavior of Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae) under visible wavelengths

Abstract

Abstract The greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae), is one of the most important pests of greenhouse crops. The intensive use of chemical insecticides has resulted in insecticide resistance in T. vaporariorum and the critical level of pesticides residue in crops. It is therefore necessary to develop new control methods based on ecological pest management. The present study was designed to control greenhouse whitefly by finding and using insect repellent wavelengths. The repellent wavelength experiment was conducted by a two-way phototactic apparatus given a choice between darkness and visible wavelength spectrum from violet (380–450 nm) to red (620–750 nm). The phototactic responses of the greenhouse whitefly were then investigated in a four-way phototactic apparatus given a choice between two light regimes, light-emitting diode (LED) and sunlight. The results indicated that the lowest (69.2%) and highest (97.8%) number of whiteflies were attracted to violet and orange (590–625 nm) spectra, respectively. In addition, the present study indicated a significant attraction of T. vaporariorum adults to sunlight compared with LED. Furthermore, the eggplants grown under growth LEDs showed a significantly higher growth rate than the plants grown under sunlight. These findings suggest that this type of LED not only has positive effects on plant growth but it also has a repellent activity on T. vaporariorum adults, leading us to develop an effective behavioral control of the greenhouse whitefly.