Submitted to: Physiological Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/3/2003
Publication Date: 4/1/2003
Citation: Yee, W.L. 2003. Effects of sucrose concentrations and fly age on feeding responses and survival of female and male western cherry fruit fly, Rhagoletis indifferens. Physiological Entomology. 28:122-131. Interpretive Summary: Western cherry fruit flies are the most serious pest of commercial cherries in the Pacific Northwest. A thorough knowledge of fly feeding biology is valuable in the development of management strategies designed to reduce insecticide use. Personnel at the Yakima Agricultural Research Laboratory in Wapato, WA, initiated studies in 2001 on the effects sucrose concentrations on feeding responses of male and female western cherry fruit flies. Flies of both sexes showed similar responses to increasingly higher sugar concentrations. Flies fed and survived longer on higher concentrations. However, even with the highest concentrations, flies usually died within 5 days, indicating a high dependence on sugars. The high dependence of both males and females on sugars indicates that sugars in some form perhaps can be incorporated into spray baits for control of flies.
Technical Abstract: The effects of single meals of different sucrose concentrations on feeding responses and survival of 8-24 h old, 1-2 d, 10-12 d, and 31 36 d old female and male western cherry fruit fly, Rhagoletis indifferens Curran, were determined. Feeding time and food consumption response patterns in both sexes within age groups were curvilinear. Feeding times increased with more concentrated wet to dry sucrose foods. Consumption of concentrated wet sucrose was high, but that of concentrated dry sucrose was low. One-2 d old flies of both sexes that had not previously fed consumed more food than unfed 8-24 h flies and 10-12 and 31-36 old flies that had been starved for 16-24 h. Females consumed more than males, but they consumed the same amount as males per mg bodyweight. When fed single 20 and 60% sucrose meals, 1-2 d old flies survived longer than flies in all other groups, with 31-36 d old flies surviving shortest. Despite age-related differences in survival, in general, no sex differences in survival were seen in flies fed sucrose within age grous, or in flies fed sucrose-yeast, cherry juice, and honeydew foods. Results indicate that sugar-feeding behaviors and the energy invested in sugar seeking by both sexes of R. indifferens in nature should be the same throughout the season.