FIELD CONTROL OF COTTON BALLWORM (Helicoverpa armigera H.) BY USING SEX PHEROMONES

Zhang Zhong-ning, Liu Xun, Lou Zhao-xiang Li Zhi-bin
Institute of Zoology, Chinese Academy of Sciences, Beijing, 100080, China

Cotton Bollworm (Helicoverpa armigera H. ) is a key pest in China. It damages about 200 crops and plants, especially cotton. From the 1990' it broke out in the cotton cultivation area in North China causing loss about ten thousands million Chinese Yuan (~ 1.2 billions USD).

Several methods were used to control the pest: chemical insecticides including many mixture ones), biological agents (especially Bacillus thurigiensis), attraction by black light, branchs of pupper tree and the use of sex pheromones.

There were pitfalls due to two mistaken views on pest management and crop protection:

1. To have a complete kill of pest insects. even 100% (without consideration economic threshold);
2. To use insecticides to cover the whole crops or plants (do not consider the serious effect of environmental pollution and ill effect on man).

The r-strategist species of insects can not be destroyed completely, such as cotton bollworm and aphids. We have to rely on chemical insecticides in the future with rational priority, but facing the r-pest insects, the resistance to insecticides and environment pollution problems are more important and we must to find a better way, a truly and effective way in integrated pest management way.

From 1992 to 1995, especially in the last two years we curried out a masse trapping field program in large scale to control the cotton bollworrn by using the sex pheromones (Z-11-16Ald and Z-9-16Ald in 95:5) in more than 30 counties four provinces in North China: Hebei, Henan. Shandong and Shanxi. The total tested area for the four years was more than four hundred thousand hectares. Some basic results were as follows:

1. Attracted male moths(average in each trap): > 20 head/day
2. Matting reduced: >38% 3. Egg reduced: : >50%
3. Matching reduced: > 45% 5. Young reduced: : > 60%