Resistance of Heliothis armigera to Insecticides in the Ord Irrigation Area, North Western Australia1

Genetic variation inHeliothisin Australia: species identification and gene flow in the two pest species H. armigera (Hübner) and H.punctigeraWallengren (Lepidoptera: Noctuidae)

“…Dispersal may be induced under conditions which delay reproductive maturity (Hackett & Gatehouse, 1982). Certainly, the rapid spread of resistance to DDT (Twine & Kay, 1973;Wilson, 1974;Goodyer et al, 1975) in the early 1970s in eastern Australia would argue that gene flow is sufficient to lead to a rapid spread of resistance throughout this area. Within this context, the lack of geographic variation in gene frequencies is consistent with, but does not confirm, the hypothesis that gene flow occurs between most, if not all, populations of H. armigera in Australia.…”

“…Both are polyphagous, and a list of their common names illustrates the variety of hosts: cotton bollworm, tobacco budworm, tomato grubworm, corn earworm, bean-pod borer, flower caterpillar, native budworm and lucerne budworm (Broadley, 1977). Despite their sympatric distributions in Queensland and New South Wales (Common, 1953), and overlapping host preferences, the two species exhibit important differences: H. armigera has developed resistance to insecticides such as DDT (Twine & Kay, 1973;Wilson, 1974;Goodyer et al, 1975), and more recently, synthetic pyrethroids (Anon., 1983), while H. punctigera remains susceptible; H. punctigera is usually a pest in crops in spring, while in irrigated crops in southern Queensland and northern New South Wales, H. armigera often reaches pest status only during summer. Furthermore, H. armigera has become a serious pest in north-western Australia and in inland areas of eastern Australia only since the advent of resistance to DDT (Wilson, 1974;Wilson et al, 1979).…”

CARBAMATE RESISTANCE INHELICOVERPA ARMIGERA(HÜBNER) (LEPIDOPTERA: NOCTUIDAE) IN AUSTRALIA

“…Insecticides are widely used for control of this insect, especially on cotton. H. armigera has a long history of insecticide resistance in Australia; to DDT in the early 1970s (Wilson 1974;Goodyer et at. 1975), to the pyrethroids in 1983 (Gunning et al 1984), and to cyclodienes and organophosphate compounds (Gunning unpubi.…”

Management of resistance to pesticides in cotton pests

“…Resistance to DDT contributed to the collapse of cotton cultivation and to economic decline of the Ord Valley projects in the early 1970s (Wilson, 1974). Further south, reliance on DDT/toxaphene mixtures, and later endosulfan and OPs provided enough control to grow cotton economically (Goodyear et al, 1975), but truly effective control of H. armigera returned only when the synthetic pyrethroids became available in 1977-78.…”

“…However, when control becomes inadequate either through the development of resistance in primary pests or through uncontrollable increases in populations of secondary pests (Dittrich et al, 1985;Eveleens, 1983) which may also become resistant (Dittrich and Ernst, 1983), the additional treatments needed to restore control can make cotton growing unprofitable. In extreme cases this can lead to the abandonment of its cultivation as happened in the valleys of the Rio Grande (Mexico and USA) and the Ord (Australia) (Reynolds et al, 1975;Wilson, 1974).…”