Submitted to: Western Orchard Pest and Disease Management Conference
Publication Type: Abstract Only
Publication Acceptance Date: December 15, 2005
Publication Date: January 10, 2006
Citation: Light, D.M., Bouyssounouse, P.I. 2006. Walnut trials using the codling moth kairomone, pear ester - mec, as an insecticide spray adjuvant. Meeting Abstract. Technical Abstract: The pear ester kairomone, in a micro-encapsulated formulation (PE-MEC) (CIDETRAK DA-MEC, Trece, Inc.), was tested for its efficacy as a spray adjuvant to various insecticides in field trials in a walnut orchard (Chandler variety) in California. To allow the adjuvant activity of the PE-MEC to be resolved, the rates of insecticides used were challenged by reducing them by as much as one-half the label rates. The insecticides tested were two OPs: choropyrifos and phosmet, an IGR: methoxyfenozide, and a granulosis virus. PE-MEC adjuvant was tested at rates of 0.2, 0.6, and 1.7 grams/acre. Treatments were reduce-rate insecticide vs. reduce-rate insecticide + PE-MEC, and treatments without insecticides were PE-MEC alone and a “blank-MEC.” Sprays were applied by hand-gun to 8 replicate single trees per treatment. Test trees were distributed in a randomized block design throughout a 20 acre walnut orchard, that received no grower sprays. Application rate of water was 3.5 gallons/tree, or 160 gallons/acre, and it was applied six times through the season due to CM flight pressure. Treatment control efficacy was evaluated through both canopy-count visual assessments and nut knock-down collections just prior to harvest in late September. Results show that the PE-MEC adjuvant reduced CM and navel orangeworm damage rates from 49% to 88% below the low damage rates incurred with insecticides alone.