Combining female removal with mating disruption for management of Cydia pomonella in apple
A. L. Knight, Michele Preti, Esteban Basoalto, María Valentina Mujica, Riccardo Favaro, Sergio Angeli
Abstract
Field studies tested the use of lure-baited traps for female removal (FR) of codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae) in apple, Malus domestica Borkhausen, treated with sex pheromone-based mating disruption (MD-FR). Four lures were evaluated, including the combination of (E,Z)-2,4-ethyl decadienoate (pear ester, PE), (E)-4,8dimethyl-1,3,7-nonatriene (DMNT), and 6-ethenyl-2,2,6-trimethyloxan-3-ol (pyranoid linalool oxide, LOX), these three components with (E,E)-8,10-dodecadien-1-ol (PH), and two lures loaded with PH/PE. All lures were used with a co-lure loaded with acetic acid (AA). Studies examined the importance of trap type and density on moth catches. Seventeen trials were conducted in 1-3 ha adjacent paired plots treated with or without 60 traps ha -1 in Washington State from 2018-2020. Paired plots were each treated with MD and a similar spray regime. The mating status of females in the MD-FR plots were compared with females collected from blocks not treated with MD. The PE/DMNT/LOX + AA lure caught significantly more females than any other lure. The most effective trap was a bucket trap with a green top and a clear bottom. Total or female moth catches per trap did not decline across trap densities from 37 to 99 ha -1 . MD-FR trials showed that levels of fruit injury could be significantly reduced 50-75% across each moth flight. The proportion of mated females was 8 to 19% lower in blocks treated with MD-FR than not treated with MD. Further studies are needed to refine key operational factors associated with MD-FR considering the economics of organic and conventional apple production across key varieties.