Application of Sex Pheromone of Asian Corn Borer (Ostrinia furnacalis) in the Field
Yen, F. C. and T. F. Huang
Synthetic sex pheromone of European corn borer obtained from Academia Sinica failed to attract male moths in the test conducted between December 1989 and July 1990 in Tainan.
The 2-days-old of virgin females showed the best results of attraction to the moths followed by the 3-days-old ones. For those females of 5-days-old or more were very little in their efficacy of attraction. The results of the experiment conducted in December indicated that the male moths were much more active around midnight and the main time of mating was found between 10 PM and 2 AM. More make moths were trapped in peanut field than corn field or fallow field. It means that the male moths preferred to lodge in the canopy of short plants.
Combinations of Z-12-tetradecenyl acetate, E-12-tetradecenyl acetate, tetradecyl acetate, and hexadecyl acetate at the ratio of 38:27:33:2 and 75:25:0:0 showed the best results of trapping, and their results were as good as 2 virgin females. Better trapping was observed in the sex pheromone imported from the U.S. (foreign country) than the local products of Z-12-tetradecenyl acetate: E-12-tetradecenyl acetate : tetradecyl acetate : hexadecyl acetate at the ratio of 38:27:33:2. The best dose for trapping of Asian corn borer was found with 1mg/trap of synthetic sex pheromone and the effectiveness could last for 30 days or more.
The results of trapping with different type of traps showed that wet type of traps was the best followed by sticky paper type and PET bottle traps. Among the various type of PET bottle traps, those opened at the rip end were better than those opened at the bottom end. However they were still worse than the sticky paper traps.
In spring, the efficiency of trapping varied in the different type of dispensers. However, no difference was observed between rubber septum and PE tube dispensers in the spring. In winter, the PE tube dispenser was closed or not did not influence the efficacy of trapping. In summer, both ends kept opened was the best.
The setting height of the traps depends on the canopy height of the plants, when the canopy height is less than 1 meter, the traps should be set higher than the growth points, when the canopy height is higher than 1 meter such as corn, the trap can be set around 1 meter high. Higher than 1 meter is difficult to manipulate in the filed.
The height population dynamics of Asian corn borer in Tainan was found between November and February in a year, followed by the population between March and May, while the population between June and September was the lowest.
Accepted for publication: September 20, 1990.