Tufted Apple Budmoth (Lepidoptera: Tortricidae): Simulation of Within-Season Phenology in North Carolina

Abstract

In-orchard temperatures and pheromone trap catch data for 21 orchard–year (1976–80) combinations were used to compare the accuracy of physiological time models in simulating and predicting the time intervals between male flight peaks of bivoltine populations of the tufted apple budmoth, Platynota idaeusalis (Walker), in North Carolina apple orchards. Linear models (degree days) were not accurate within ±1 wk for simulating the time intervals between flight peaks for more than 16 of the 21 orchard–year combinations. A nonlinear model simulates within ±1 wk the interval between flight peaks for 20 of the 21 orchard–year combinations provided that the time of the peak of the first flight is known, the model simulates two generations rather than one, and orchard temperatures are known. The nonlinear model predicts (±1 wk accuracy) second flight peaks several weeks in advance by using actual orchard temperatures during the first 80% of P. idaeusalis development and then using 5-yr (1976–80) average hourly orchard temperatures during the final 20% of development.