inches away from the trap base. For treatment 5, the 

 15 vials were hung from a wooden stick (about 10 

 inches long) using wire. The stick holding 

 benzaldehyde-releasing vials was then attached 

 horizontally to apple tree branches using wire so that 

 bases of vials were located about 4 inches above a 

 cylinder trap top. 



In this test, benzaldehyde was evaluated in 

 combination with grandisoic acid (PC pheromone) 

 (ChemTica Intemacional, S.A., San Jose, Costa Rica). 

 One pheromone dispenser, releasing about 1 mg of 

 grandisoic acid per day, was placed inside each 

 benzaldehyde-baited trap top. 



All vials containing benzaldehyde were replaced 

 on June 15. Traps were deployed within a single row 

 of apple trees and were inspected for PC captures 2-3 

 times per week. Trap tops were rotated one position 

 (clockwise) at each inspection. 



Experiment 3. This evaluation was performed from 

 May 25 to June 20, 2001, simultaneously at the 

 UMASS Cold Spring Orchard Research & Education 

 Center in Belchertown, Atkins orchard, and in backyard 

 trees in Amherst, MA. The experiment was aimed at 

 determining the longevity of four different formulations 

 of benzaldehyde alone (without pheromone) using 

 cylinder traps. The formulations evaluated were the 

 same as those described in experiment 1. All 

 benzaldehyde-releasing dispensers were positioned 

 inside cylinder trap tops. Traps 

 were inspected for PC captures 

 2 to 3 times per week, rotating 

 the trap tops one position 

 (clockwise) at each inspection. 



Experiment 4. This test was 

 conducted from June 26 to July 

 2, 2002 in backyard trees in 

 South Deerfield, MA, using 

 Circle traps. The purpose was to 

 determine the influence of 

 different release rates of 

 benzaldehyde, in association 

 with PC pheromone, on PC 

 captures. We evaluated three 

 different release rates of 

 benzaldehyde (10, 20, and 40 

 mg/day) together with a control 

 treatment without benzaldehyde. 



Benzaldehyde was released 

 from 15-ml low-density white 



polyethylene vials (Wheaton, Millville NJ). Each vial 

 was filled with 15 ml of benzaldehyde to achieve a 

 release rate of ~10 mg/day. Each vial was hung by its 

 neck from a wire and placed inside an inverted, green 

 266-ml plastic cup to provide additional protection for 

 this chemical against polymerization by UV light and 

 rainfall. Cups were hung from tree trunks using wire 

 in such a way that bases of cups were about 4 inches 

 above Circle trap tops. Depending on the treatment, 

 either no, one, two, or four cups were positioned above 

 the Circle trap tops. 



In all, 32 Circle traps were deployed on unsprayed 

 apple tree trunks. Each was baited with one of the 

 abovementioned treatments and one dispenser releasing 

 PC pheromone (release rate: 1 mg/day) placed inside 

 the Circle trap top. Traps were inspected for PC 

 captures one week after bait deployment. 



Results 



In the first experiment, no appreciable differences 

 among odor-formulations were noticed when 

 comparisons were made among vials placed outside 

 of trap tops (Table 1 ). However, when vials were placed 

 inside of trap tops, the '4 clear vials' formulation proved 

 to be the most attractive formulation for PCs, followed 

 by the '1 white vial' formulation. When PC captures 

 by traps were compared according to position of vials 



Fruit Notes, Volume 67, Fall, 2002 



