Field programs initially developed in the United States with DiPel ES (Bacillus thuringienses) and its combinations with new ovicides and synthetic pyrethroids were successfully tested in Australia during the 1989-90 season. A total of 23 trials was completed which demonstrated that the use of DiPel ES alone or combined with chemical insecticides would be a suitable material to include in the pyrethroid resistance management program in that country for control of their most serious lepidopterous pests in cotton, Heliothis armigera and H. punctigera.

A field program with DiPel ES continued throughout 1990 in the U.S. which had as its objective the evaluation of new application procedures and new formulation development.