Submitted to: The Canadian Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 5, 2005
Publication Date: November 1, 2005
Citation: Knight, A.L., Light, D.M. 2005. Timing of egg hatch by early-season codling moth (Lepidoptera: Tortricidae) predicted by moth catch in pear ester and codlemone-baited traps. Can. Entomol. 137(6):728-738. Interpretive Summary: Growers predict the start of egg hatch of codling moth with the onset of catching male moths in sex pheromone-baited traps. Insecticide applications are timed with this approach to improve the management of this destructive pest. The limitations of this approach are that sex pheromone-baited traps catch only males and predictions of egg hatch are subject to errors due to differences between the sexes in emergence timing and variability among orchards and between years in the onset of egg laying due to the influence of cool temperatures on female moth’s sexual behaviors. Recently, a chemical derived from pear fruit, pear ester, has been shown by ARS researchers to be attractive to both male and female codling moths. Monitoring female moths directly with pear ester may allow growers to more accurately time female emergence in the season and the occurrence of egg laying by females and subsequent egg hatch. Studies were completed from 2000-2002 to compare the use of pear ester versus sex pheromone-baited traps. Our results suggest that timing egg hatch from the start of sustained catch of female codling moths in pear ester-baited traps may be an improvement over the current use of sex pheromone-baited traps. In addition, we found that the accuracy of this prediction can be further improved by selecting the exact start of female moth’s sexual activity by considering the daily maximum and dusk temperatures that occur between trap checks.