BRAIN

Many insects rely on sight to survive. This color sheet was created by skillfully utilizing the visual behavioral characteristics of insects. Small pests do not fly aimlessly, but fly toward a specific target while controlling their attitude. Junya Yase, a researcher at the The Hyogo Prefectural Research Institute for Agriculture, Forestry, Fisheries , observed which parts of the patterned sheet had the most pests flying nearby, and found that many pests gathered around the patterns. It was found that pests use the borders (edges) created by patterned colors and the background (backdrop) as a visual target. This phenomenon is referred to as the "visual edge effect".

Therefore, with the cooperation of Daikyo Giken Kogyo Co., Ltd., yellow sheets printed with many shaded diamond patterns (Fig.1) and yellow sheets without diamond patterns were installed in a tomato cultivation greenhouse. An investigation regarding which sheet type could catch more pests was conducted. The diamond-shaped edge pattern mimics the leaves of a plant. Both sheets are coated with an adhesive that insects become stuck to. The results of experimentation revealed that sheets with an edge pattern caught more whiteflies (Fig.2) than sheets without the pattern. By simply adding an edge pattern to a conventional sheet, the effect of attracting pests increased.

If so, how many edge patterns should be drawn on the sheet? As a result of the experiment using whiteflies, it was found that a sheet with a length of 260 mm and a width of 115 mm with 26 edge patterns had the highest trapping rate. Based on the relationship between the reflected wavelength and insect trapping efficiency, it was found that it was best to draw a specific greenish pattern on a sheet with a yellow background.

These practical advantages were highly evaluated, and this product was awarded the "2020 MONODZUKURI Innovative Parts and Components Award" (MONODZUKURI Life Civilization Institute Chairman's Award). In order to support the improvement of the competitiveness of Japanese product creation, this award recognizes parts and materials that are "unsung heroes" contributing to the development of industry and society.

According to Yase, a researcher who investigated the effect of controlling whiteflies, "because the edge patterned sheet catches the whitefly parents, the number of larvae generated in the greenhouse was reduced to one-fourth the number when there were no sheets."

This insect trapping sheet can also be used for trapping leaf miner flies (Fig.4), thrips (Fig.5), and Japanese beetles. The optimum number of sheets to be placed is 200 to 500 sheets per 10 ares, and the sheets are sold at around 55 to 60 yen per sheet. It is also a great advantage that the sheets can be used in combination with insect repellent nets, light irradiation, pesticides, etc.