Studies were conducted in 0.07- to 0.18-ha peach and apple plots to determine the effects of pheromone trap and hand-applied emulsified wax pheromone dispenser application heights on captures of Grapholita molesta in traps baited with pheromone lures or virgin females. Traps and pheromone dispensers were placed either low (1.2–1.8 m) or high (2.7–4 m) within tree canopies. In the majority of cases, equivalent numbers of male G. molesta were caught in traps placed at the low and high positions in both pheromone-treated and untreated plots. Furthermore, pheromone dispensers placed at the low and high positions equally disrupted orientation of male G. molesta to pheromone traps placed at either height and to virgin female traps placed at 1.2–1.8 m within canopies season-long at most sites. Our results indicate that for trees ≤3.5 m tall, dispensers with release rates ≥18 mg/ha/h placed at 1.5–2.0 m (heights easily reached from the ground) should effectively disrupt mating of G. molesta throughout tree canopies. In trees between 3.5 and 4.5 m tall, the dispensers should be moved to ≈1.5 m from the top of the canopy. For trees taller than 4.5 m, we recommend hanging dispensers both in the top and bottom thirds of tree canopies. Most commercial Michigan peach and apple trees are <3.5 m tall. Eliminating the need to apply dispensers high in the canopy in most orchards will enable growers to reduce application costs, thereby facilitating increased adoption of mating disruption for G. molesta control by growers.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.