STUDIES ON THE MANAGEMENT OF PYRETHROID RESISTANCE IN BOLLWORM POPULATIONS IN COTTON FIELDS

Abstract

Many previous studies revealed the high resistance of pink and spiny bollworms to insecticides in the cotton fields. In Egypt, several pyrethroids have been widely used against cotton pests in general and bollworms in particular since the late 1970s. However, although pyrethroid insecticides were the most efficient and widely used against bollworms but the onset of resistance development to these compounds in bollworms have been recently documented (Haynes eta/., 1987; Miller eta/., 1988; Knight and Hull, 1989).

Detection of changes in response is needed, especially in the early stages of resistance development. Monitoring insecticide resistance in field population moth of bollworms is of great importance in sound resistance management programs (Tabanshink and Croft, 1982; Plapp eta/., 1987). In Egypt, very few dose mortality studies have been done with bollworm (Osman eta/., 1991; Al­ Beltagy eta/., 1996).

Therefore, it is important to study the resistance of bollworms (pink and spiny) to pyrethroids in Egyptian cotton fields, to establish a program for controlling and reducing the resistance level of these pests to pyrethroids. Such a program could be efficiently used to reduce number of insecticide sprays, cost of insecticides used, and increase the production of cotton per unit.

In the present .studies, the resistance management of the bollworms (pink and spiny) against the pyrethroid insecticides was studied in cotton field in Abo­ Hommos district, El- ehera Governorate, by using attracticide sex pheromone in two different areas. In the first area, the recommended program of chemical insecticide was used, while in the second the pheromone treatment was used, on the adult pink and spiny bollworms, during 1996 and 1997 cotton seasons.