A COMPUTERIZED PHENOLOGY MODEL FOR PREDICTING BIOLOGICAL EVENTS OF RHAGOLETIS INDIFFERENS (DIPTERA: TEPHRITIDAE)

Abstract

AbstractA phenology model based on a time–temperature relationship has been developed for the western cherry fruit fly, Rhagoletis indifferens Curran. The model predicts the occurrence of various biological events such as emergence levels, mating, oviposition, larval appearance, parasite activity, and pupation. These events are predicted as a function of summation of thermal units (TU) starting 1 March. For example, emergence begins at 462, oviposition at 541, hatch at 594, and pupation at 795 TU. The model was validated by actual field observations for a period of 3 years (1976–1978). Extended validation of first emergence was obtained from an entirely different cherry growing area, the Hood River Valley. The model could be a useful tool in integrated pest management program on cherries.