Field Study on Pheromone Traps in Capturing Helicoverpa armigera Hiibner Moths During the night

Abstract

The synthetic pheromone : Z-11-HDAL and Z-9-HDAL at the ratio of 97 :3 at the rate of 2.0 mg. in 0.1 ml. hexane per dispenser applied with the simplified traps had already proved successful in capturing male moths of the American bollworm (Heli coverpa armigera Hubner) in Thailand. To investigate the moth activity during the night period. Four traps were installed at 40 meters apart and each was 1.50 meters high above the ground level. The moths were collected at 2 hour intervals from 18.00 - 06.00 hr. for five consecutive nights (replications). It was fiybd tgat tge nizunyn caotyre or 57.6% was obtained during 04.00-06.00 hr. In the orher periods. or29.3 , 9.4 , 2.1 1.7 , and 0.0% were caught during 02.00-04.00 , 24.00-02.00 , 18.00-20.00 , 22.00-24.00 , and 20.00-22.00 hl., respectively.