How blueberry attributes influence oviposition behavior of the invasive spotted wing drosophila, Drosophila suzukii (Matsumura)

Drosophila suzukii is an invasive pest of soft and thin-skinned fruits. The susceptibility of its host fruits and cultivars varies. A study was conducted to evaluate different quality attributes of southern highbush (SHB) and rabbiteye (RE) blueberry cultivars and their influence on oviposition by D. suzukii females. Berries from six cultivars of SHB and RE blueberries were harvested from 4 groups (replicates) of 4 bushes and checked for D. suzukii infestation. The skin color, size, penetration force, and soluble solids content were measured for 30 berries from each replicate. No-choice assays were conducted using five assays per replicate (20 per cultivar), each with one berry and one female fly for 2 h. Choice assays were conducted in a 0.75 m³ clear chamber with a wire mesh floor and constant downward air flow. Ten berries of each cultivar (6) wrapped in clear netting, were hung equidistant from the top of the chamber and around a central fly release point on the floor. Flies (70 female, 30 male) were released in the chamber for 72 h. Eggs laid and adults emerged were counted 24 h and 14 d, respectively, after fly introduction in choice and no-choice assays. Results suggest differences in the susceptibility of different cultivars.