Rainfastness of a Microencapsulated Sex Pheromone Formulation for Codling Moth (Lepidoptera: Tortricidae)

Abstract

The rainfastness of a microencapsulated sex pheromone formulation for codling moth, Cydia pomonella (L.), was evaluated in a series of laboratory experiments with detached apple, pear, and walnut leaves. Increasing the intensity and duration of simulated rainfall significantly increased the removal of microcapsules from both the top and bottom of apple leaves. The removal of microcapsules was significantly higher from the top versus the bottom of leaves at all rates tested. Leaf angle was a significant factor affecting the removal of microcapsules from the top surface of apple leaves with fewer microcapsules removed, because leaves were oriented with a steeper downward angle. Both leaf surfaces of apple and pear retained a higher proportion of microcapsules than walnut leaves, and the bottom surface of apple leaves retained significantly more than pear leaves. Three spray adjuvants were evaluated as stickers for microcapsules. No difference was found in the number of microcapsules deposited on apple leaves among three stickers tested at rates from 0.06 to 0.25%. However, in a second test a latex sticker significantly increased the deposition of microcapsules on apple leaves compared with a polyvinyl polymer and a pine resin sticker at a rate of 0.06%. Significantly more microcapsules were retained on the bottom versus the top of apple leaves with all stickers. The latex and polyvinyl stickers significantly increased the retention of microcapsules versus the pine resin sticker and the control on apple leaves. In another test, the addition of 0.06% latex sticker did not increase the deposition of microcapsules on any of the three leaf types. However, the addition of the latex sticker significantly increased the retention of microcapsules on the top of apple and pear leaves and the bottom of apple leaves. The addition of a latex sticker did not affect the retention of microcapsules on walnut leaves.

Characterization of Microencapsulated Pear Ester, (2E,4Z)-Ethyl-2,4-decadienoate, a Kairomonal Spray Adjuvant against Neonate Codling Moth Larvae

“…PheromoneMECs used for mating disruption control of lepidopterous moths, which requires the emission of pheromone three-dimensionally a Individual larvae released at the center of filter papers and observed for 5 min; treatments were pipetted onto filter papers and then dried and aged in a fume hood for 4 h prior to the initial day 0 of testing, then allowed to evaporate volatiles, and age for 7, 14, and 20 days before retesting; n = 7. b One-way ANOVA, F 7,55 = 3.105, P = 0.009; means followed by a different letter are significantly different based on an all pair-wise multiple comparison procedure using the Fisher LSD method. throughout large-volume crop canopies, have specifications for application in the range of 12 to 70 g/ha pheromone, with spray applications having observed capsule densities on sprayed leaves of <1.0 to >12.5 microcapsules/cm leaf surface (31)(32)(33). In contrast, this larval-targeted PE kairomone MEC is specified for application at 3.0 g/ha PE, with microcapsules ranging from 2 to 8 μm and estimated capsule densities of up to 3.31 Â 10 3 microcapsules/cm of sprayed surface and emission levels in the picogram range.…”

Efficacy and mode of action of female‐equivalent dispensers of pheromone for mating disruption of codling moth

“…Microencapsulated formulations of pheromones are deployed with standard agricultural air‐blast sprayers, replacing the need for hand application. Although such sprayable formulations are highly desirable from a practical standpoint, their efficacy has been inconsistent and short‐lived in the field (Epstein et al , 2003; Knight & Larsen, 2004). A recently developed low volume application method, which yields high densities of clusters comprised of hundreds of microcapsules on tree foliage, has improved efficacy and increased longevity of sprayable formulations for codling moth (Knight & Larsen, 2004).…”

Evaluation of aerosol devices for simultaneous disruption of sex pheromone communication in Cydia pomonella and Grapholita molesta (Lepidoptera: Tortricidae)

“…Sprayable pheromones consist of microscopic capsules that are deployed via air-blast sprayers alleviating the labor-cost associated with hand-application of reservoir dispensers (Kovanci et al 2005;Il'ichev et al 2006). Sprayables have proven highly eVective for G. molesta (Trimble et al 2004;Kovanci et al 2005;Il'ichev et al 2006); but, less eVective for C. pomonella (Epstein et al 2003;Knight and Larsen 2004). Hercon Disrupt CM Xakes (Hercon, Emigsville, PA, USA) and Scentry NoMate CM Fibers (Scentry, Billings, MT, USA) (Swenson and Weatherston 1989) are also machine-applied to crops via custom applicators.…”