Mechanized Applicator for Large-Scale Field Deployment of Paraffin-Wax Dispensers of Pheromone for Mating Disruption in Tree Fruit

• Published in: Journal of economic entomology Vol. 99; no. 5; pp. 1705 - 1710
• Main Authors: Stelinski, L. L., Miller, J. R., Ledebuhr, R., Gut, L. J.
• Format: Journal Article
• Language: English
• Published: Lanham, MD Entomological Society of America 01-10-2006
• Subjects: Animals; apples; application equipment; Biological and medical sciences; competitive attraction; Control; dispensers; emulsifiable wax; Female; Fundamental and applied biological sciences. Psychology; Generalities; Grapholita molesta; HORTICULTURAL ENTOMOLOGY; insect control; Insect Control - instrumentation; Male; Malus - parasitology; Malus domestica; mating disruption; mechanization; Moths - drug effects; orchards; oriental fruit moth; Paraffin; paraffin wax; pheromone dispensers; Phytopathology. Animal pests. Plant and forest protection; Protozoa. Invertebrates; Sex Attractants - administration & dosage; sex pheromones; Sexual Behavior, Animal - drug effects; wax drops; Attraction; Grapholita molesta; Mating disruption; Insecta; Pheromone; emulsifiable wax; Wax; Tortricidae; oriental fruit moth; Arthropoda; Lepidoptera; Crapholita molesta; competitive attraction; Fruit tree; Invertebrata; Semiochemicals
• ISSN: 0022-0493; 1938-291X
• DOI: 10.1603/0022-0493-99.5.1705

A tractor-mounted mechanized applicator was developed for large-scale deployment of paraffin-wax dispensers of pheromone for mating disruption of oriental fruit moth, Grapholita molesta (Busck). The wax formulation was mostly water and emulsified paraffin wax containing 5% (by weight) pheromone [93:6:1 blend of (Z)-8-dodecen-1-yl-acetate:(E)-8-dodecen-1-yl-acetate:(Z)-8-dodecen-1-ol]. Ten milliliters of wax was applied per tree as ≈160 deposits (0.04 ml of wax per drop). An average of 23 min was required to treat 1 ha of crop. Disruption efficacy of mechanically applied wax was measured relative to an untreated control in replicated 0.4-ha blocks within a recently abandoned apple orchard. From 6 May to 27 June, 100% disruption of tethered virgin females and 97% inhibition of pheromone traps was achieved for 52 d with two applications of wax. However, during mid- to late summer (July–August), this level of efficacy was maintained for only ≈1 wk after each of two applications. Higher temperatures later in the season may have accounted for abbreviated efficacy of the applied small drops. Mechanically applied paraffin-wax technology may increase adoption of mating disruption given that a higher level of efficacy was achieved despite deploying less active ingredient per hectare relative to that used with reservoir dispensers. The savings in labor by not requiring hand application of reservoir dispensers could be directed toward cost of machinery. However, the short duration of efficacy obtained with the current wax formulation and mechanical applicator is judged uneconomical given the eight or more applications that would have been required for high-performance disruption over the full season. Larger drops with lower surface area-to-volume ratios are expected to prolong pheromone release for extended efficacy and desirable overall economics.