The reliance of the Australian cotton industry on insecticides for the control of insect pests represents a major economic and environmental concern. In the face of pesticide resistance in H.

A widespread problem of premature defoliation and physiological cut out of cotton has occurred in the Emerald Irrigation Area since the early 1980s. The problem was particularly severe in 1988 and 1989.

Last season there were four (Siokra 1-4, Siokra L22, Sicala 33 and CS 189) CSIRO mainstream varieties being grown commercially in most districts.

The cornerstone of most pest management programs world-wide is the "Economic Threshold" concept which is based on the principle of controlling a pest only if it is economically prudent to do so i.e.

Previous research at Narrabri Agricultural Research Station and elsewhere has shown that mite populations increase more slowly on okra leaf cotton genotypes than on normal leaf genotypes (Bailey et al., 1978; Thomson,