Ants as egg predators of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Australian cotton crops

Abstract

Helicoverpa armigera is a major pest of Australian cotton crops. To assess the impact of ant predation on H. armigera populations, the behaviour of four common ant taxa was observed in cotton crops in northern New South Wales over the 1999-2000 and 2001-02 seasons. Areas of cotton were artificially stocked with H. armigera eggs prior to observation. Pheidole spp. were the most frequently observed ants within the crop canopy in 1999-2000 and took the most H. armigera eggs. Iridomyrmex spp. were more frequently observed than Pheidole spp. in 2001-02 and also took some H. armigera eggs. Neither Paratrechina spp. nor Rhytidoponera metallica (Smith) took any H. armigera eggs, although both were seen in the crop canopy. Irrigation, cultivation and insecticide application disrupted foraging ants and limited their impact on H. armigera populations.

Cotton fertilization using PGPR Bacillus amyloliquefaciens FZB42 and compost: Impact on insect density and cotton yield in North Benin, West Africa

“…This may be explained by the presence of natural enemies of these pests in the experimental plots. For instance, Chrysopids and ant species, which are known as the most important predators of H. armigera (Alavo, 2006;Mansfield, Elias, & Lytton-Hitchins, 2003;Romeis & Shanower, 1996;van den Berg, Cock, & Oduor, 1997;van den Berg & Cock, 1993, 1995, were occasionally encountered in the plots. We considered that the presence of these beneficial organisms in the plots was due to the fact that these plots have not been treated with any chemicals.…”

Predacious activity of Ants (Hymenoptera: Formicidae) in conventional and in No-till agriculture systems

“…The ants of the genus Odontomachus are generalist predators of the small invertebrates and can be found foraging on the soil surface at day and night, as well as in low vegetation and tree trunks (Briese and Macauley, 1981). In a study on the impact of the ant predation on Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) eggs in the cotton monoculture in Australia, Mansfield et al (2003) found that most eggs were attacked by the ants belonging to the genus Pheidole. Species of the genus Solenopsis are the most abundant group of the predators in the agroecosystems, therefore are important predators of a wide variety of the insects, including the pests of several crops (Eubanks, 2001).…”

“…A large number of studies on the ant communities in the tropics were conducted in the natural ecosystems, although the evidence of similar ant functions in the agroecosystems can be found, particularly among the communities of the insects considered pests (Samways, 1983;Mansfield et al, 2003;Rossi and Fowler, 2004) or weeds (Risch and Carroll, 1982). The studies conducted in the Dourados region (MS, Brazil) showed the genera of Pheidole, Solenopsis, Dorymyrmex and Ectatomma as the insect predators in soybean (Fernandes et al, 1999).…”

Invasive ants in Australia: documented and potential ecological consequences

“…and, to a lesser extent, Iridomyrmex spp. are predators of the cotton bollworm Helicoverpa armigera, but agricultural practices limit their effectiveness as controls (Mansfield et al 2003). Iridomyrmex spp.…”