Effect of Color and Contrast of Highbush Blueberries to Host-Finding Behavior by Drosophila suzukii (Diptera: Drosophilidae).

Drosophila suzukii Matsumara (Diptera: Drosophilidae) has become a serious pest in soft-skin fruits and berries, infesting both ripe and ripening fruits. Crop damage in highbush blueberry has been particularly severe. During blueberry fruit development, fruits of various degrees of ripeness are present simultaneously. In addition, foliage color changes as the season progresses. We investigated the influence of blueberry fruit and leaf color on host-finding behavior in D. suzukii. Opposing shifts between reflectance spectra of ripening fruits and senescing leaves increased contrast between ripe fruit and senesced foliage. Developmental changes in contrast between fruit color and leaf color may act as a visual contextual cue in finding suitable host fruits. Opposing shifts in reflectance spectra of ripening fruits and senescing leaves increased the contrast between ripe fruit and senesced foliage. These opposing changes in color may contribute to the attractiveness of blueberry fruit as a late season host for D. suzukii.