Disruption Effect of the Synthetic Sex Pheromone and its Analogues on Diamondback Moth

Five mg and 50 mg of sex pheromone (Z-11-16:Ald, Z-11-16:Ac and Z-11-16:OH), 5 mg and 10 mg of Z-9-14:Ac and 1 mg and 10 mg of Z-11-16:OH were tested to show the disruption effect on diamondback moth, Plutella xylostella (L.), in a field. When the distance between the sticky trap and tested chemical was zero or 2.8 m, the chemicals did not show the disruption effect. However, when the distance increased to 6.3 or 8.4 m, all tested chemicals, except 1 mg of Z-11-16:OH, showed the disruption effect. In control traps more males were attracted to the long distance (6.3 and 8.4 m) than to the short one (0 and 2.8 m). The data obtained from this observation suggest that the active space of DBM in the field is possibly between 0 and 6.3 m.