Communication disruption of Epiphyas postvittana (Lepidoptera: Tortricidae) by using two formulations at four point source densities in vineyards.

Light brown apple moth [Epiphyas postvittana (Walker)] is now established as an economic and quarantine pest in California, and new technologies are being investigated to increase options for its management. Two new organic formulations for mating disruption, SPLAT LBAM HD-O and organic Hercon Biotie (biodegradable) were field tested at four point source densities (25, 72, 322, and 500/ha) and compared with the standard Isomate LBAM Plus (500/ha, as a positive control) and an untreated (negative) control. Assessment involved trapping using synthetic lures and virgin females. In total, 175,776 male light brown apple moths were caught to both the caged females and synthetic lures, from 10 February to 19 May 2011. The light brown apple moth catch dramatically decreased from baseline measurements after the treatments were applied, with the highest density treatments reducing catch to below 10% of the catch in the untreated controls within the first week (> 90% disruption). In synthetic lure traps, the SPLAT and Biotie treatment performed similarly well over all rates (P = 0.317 for posttreatment percentage communication disruption), but SPLAT performed better at disrupting virgin female traps (P = 0.045). There was a significant increase in disruption with an increasing number of points/ha (P < 0.001). Disruption of communication was similar for all three technologies (SPLAT, Biotie and Isomate) at 500 points/ha for both types of trap (P > 0.74). Disruption of this species in vineyards is thus highly feasible.