Increasing catches of adult moth pests (Lepidoptera: Tortricidae) in pome fruit with low-intensity LED lights added to sex pheromone/kairomone lure-baited traps

Abstract

Studies of moth pests (Lepidoptera: Tortricidae) of pome fruit in Washington State, USA, evaluated the addition of low-intensity light-emitting diode (LED) lights to traps baited with sex pheromone or kairomone lures. Species included codling moth (CM), Cydia pomonella (L.), oriental fruit moth (OFM), Grapholita molesta (Busck), oblique banded leafroller (OBLR), Choristoneura rosaceana (Harris), and eye-spotted budmoth (ESBM), Spilonota ocellana (Denis and Schiffenmüller). Lures included (E,E)-8,10-dodecadien-1-ol (codlemone) plus (E,Z)-2,4-ethyl decadienoate (pear ester) and acetic acid (AA) (Combo) and a blend of pear ester, (E)-4,8-dimethyl-1,3,7-nonatriene, pyranoid linalool oxide, and AA (4K) for CM; a three-component OFM sex pheromone ((E)-8-dodecen-1-yl-acetate, (Z)-8-dodecen-1-yl acetate, and (Z)-8-dodecen-1-ol) plus codlemone and terpinyl acetate plus AA for OFM; and 2-phenylethanol and AA for OBLR and ESBM. Traps baited with only LEDs were not attractive for any of these tortricids. The addition of a LED to lure-baited traps increased male and female catches 2-12-fold across the four pest species. The proportional increase in CM catches with the LEDs was similar with both the Combo and 4K lures. Traps baited with the 4K lure caught significantly more CM with a UV LED than with either blue or green LEDs. The proportion of females caught in traps that were mated did not change with the use of the lights across species. Significantly more CM of both sexes were caught in the adhesive on the side of the liner nearest the LED. The addition of LEDs sometimes increased the by-catch of minute insects, but liners' saturation was never a factor impacting targeted moth catch. Adding the LED light significantly increased the catch of ESBM in CM-baited traps and CM in OFM-baited traps, respectively. The development of inexpensive, dual-modality traps that add a light stimulus to a kairomonal-based lure may improve direct control of these key orchard pests via female removal.