ORIENTATION DISRUPTION OF CTENOPSEUSTIS-HERANA

Orientation disruption of C. herana was tested using pheromone traps b aited with synthetic lures in small plot trials in apple orchards, usi ng polyethylene rope dispensers (100/0.1-ha plot). Dispensers released either (a) 100% (Z)-5-tetradecenyl acetate (pheromone of C. herana), (b) a blend of 25% (Z)-5-tetradecenyl acetate and 75% (Z)-8-tetradecen yl acetate (multiple species disruptant blend), or (c) a blend of 50% (Z)-8-tetradecenyl acetate and 50% saturated tetradecenyl acetate (phe romone of Planotortrix octo). Blends (a) and (b) were effective at red ucing trap catch by up to 100%, but disruption was not achieved with ( c). Experiments with lures containing pheromone compared to pheromone plus (Z)-8-tetradecenyl acetate showed reduced attraction to (Z)-5-tet radecenyl acetate with the addition of (Z)-8 (1:3). These results indi cate reduced attraction to lures but not disruption of orientation beh avior from background release of this compound and in contrast to the reduced attraction and disruptive effect of the C. herana pheromone (a ) on P. octo. Disruption of C. herana using the multiple species disru ptant blend (b) deserves further investigation.