PYETHROID RESISTANCE IN HELIOTHIS ARMIGERA (HÜBNER) COLLECTED FROM UNSPRAYED MAIZE CROPS IN NEW SOUTH WALES 1983–1987

Open Access
Publisher Website
Google Scholar
Abstract
Between 1983 and 1987 a survey of pyrethroid resistance in H. armigeru was conducted using samples collected in unsprayed maize crops in New South Wales. The average resistance levels were calculated for early, middle and late stages of each season. Data from the 4 year survey showed 2 periods of similarity. There was low resistance in the 1983/84–1984185 seasons, followed by a major increase in levels 1985/56–1956/87. Almost 50% of H. armigera sampled were pyrethroid resistant individuals in late 1986/87. Reasons for the contamination of refugia by pyrethroid resistant H. armigera and the long term implications to pyrethroid resistance management are discussed. The contamination of non‐sprayed populations by pyrethroid resistance is compared to the spread of DDT resistant H. armigera in New South Wales in the early 1970s.