Developing a Phototactic Electrostatic Insect Trap Targeting Whiteflies, Leafminers, and Thrips in Greenhouses

Abstract

Our aim was to develop an electrostatic apparatus to lure and capture silverleaf whiteflies (Bemisia tabaci), vegetable leafminers (Liriomyza sativae), and western flower thrips (Frankliniella occidentalis) that invade tomato greenhouses. A double-charged dipolar electric field producer (DD-EFP) was constructed by filling water in two identical transparent soft polyvinyl chloride tubes arrayed in parallel with fixed separation, and then, inserting the probes of grounded negative and positive voltage generators into the water of the two tubes to generate negatively and positively charged waters, respectively. These charged waters electrified the outer surfaces of the opposite tubes via dielectric polarization. An electric field formed between the oppositely charged tubes. To lure these phototactic insects, the water was colored yellow using watercolor paste, then introduced into the transparent insulator tubes to construct the yellow-colored DD-EFP. This apparatus lured insects in a manner similar to commercially available yellow sticky traps. The yellow-colored DD-EFP was easily placed as a movable upright screen along the plants, such that invading pests were preferentially attracted to the trap before reaching the plants. Furthermore, pests settling on the plants were attracted to the apparatus, which used a plant-tapping method to drive them off the plants. Our study provided an experimental basis for developing an electrostatic device to attract and capture insects that enter greenhouses.

An Electrostatic Pest Exclusion Strategy for Greenhouse Tomato Cultivation

“…The DD screen was constructed by using a PVC tube through which a metal wire was passed for insulation [9]. As water may be used as a conductor in DD screens [10], we used charged water to dielectrically polarize the insulator tube. Watercolor paint was added to the water to construct a colored DD screen.…”

“…Greenhouse tomatoes have several insect pests including the whitefly (Bemisia tabaci [Gennadius] [Hemiptera: Aleyrodidae]) [6][7][8][9][10], green peach aphid (Myzus persicae [Sulzer] [Hemiptera: Aphididae]) [6,7], western flower thrips (Frankliniella occidentalis [Pergande] [Thysanoptera: Thripidae]) [6,7,10], tomato leaf miner (Liriomyza sativae Blanchard [Diptera: Agromyzidae]) [8,10,11], and shore fly (Scatella stagnalis [Fallén] [Diptera: Ephydridae]) [6,7]. In this study, we evaluated the performance of various electrostatic pest control devices by using some of these pests.…”

Electrostatic Insect Repulsion, Capture, and Arc-Discharge Techniques for Physical Pest Management in Greenhouses

“…Takikawa et al [31,32] used a yellow-colored insulated conductor to fabricate a colored DD screen. For this purpose, the conductor metal wire in the insulator coating was changed to water.…”

“…In this screen, the yellow-colored tubes of the two units were arranged in an off configuration (Figure S4C). The yellowcolored DD screen was highly effective at attracting and trapping whiteflies, thrips, and leaf miners distant from the apparatus in the greenhouse [31]. The wide selection of commercially available watercolors is useful for constructing devices with the coloration most suitable for attracting phototactic insect pests.…”

“…The insulated conductor wire is prepared by passing a metal wire through an acrylic cylinder or soft polyvinyl chloride tube for insulation, and it is washable for reuse. Importantly, a change in conductor material from metal wire to water enabled the construction of a yellow-colored DD screen [31,32]. Because water conducts electricity, a transparent polyvinyl chloride tube filled with charged water (with watercolors) could be electrified to form an electric field for capturing insects.…”