Manipulation of landing behaviour of two whitefly species by reflective foils

Abstract

AbstractWhiteflies are major pests on several vegetable and ornamental crops. Landing behaviour is strongly influenced by wavelength (nm) of reflected light from ground and surrounding vegetation. This paper deals with manipulation of whitefly landing behaviour in semi-field greenhouse experiments using background foils, either white foils with high reflection of short wavelength radiation or green foils reducing contrast between target plants and background (soil). The reactions of two different whitefly species were compared to detect possible differences between specialist (Aleyrodes proletella) and generalist (Trialeurodes vaporariorum) species. Dual-choice experiments were performed in a greenhouse using ice-lettuce, Lactuca sativa var. capitata (T. vaporariorum) and broccoli, brassica oleracera var. Italica P (A. proletella) as model plants. The results show strong impact of the white reflective foil in controlling landing behaviour of both species, whereas the effect of the contrast-minimising foil was much lower. Light influence was stronger on generalist than on specialist species. Mechanisms behind these effects and opportunities for inclusion in an integrated pest management strategy are discussed.