Exotic invasive species are frequently introduced into the United States and billions of dollars are invested yearly in eradication and control efforts. However, invasive species can also benefit agriculture. Our research seeks to determine whether red imported fire ants affect cotton aphid population densities and whether red imported fire ants are important predators of lepidopteran pests of cotton. Fire ants were excluded from plots using applications of Extinguish® and Amdro®. Cotton aphid populations were higher in plots with ants present, on some sampling dates, apparently due to tending and guarding by ants. In experiments with sentinel bollworm eggs, significantly more eggs were absent after 24 hours of exposure in plots with ants (66%) relative to plots without ants (39%) (P<0.001). Additional field observations confirmed that ants are important predators of bollworm and beet armyworm eggs. Moreover, these observations suggested that while most predators feed in situ, fire ants remove eggs from cotton plants. In general, fire ants appear to promote cotton aphid populations early in the growing season and actively predate bollworm and beet armyworm eggs late in the season.
Species 1: Hymenoptera Formicidae Solenopsis invicta (Red imported fire ant)
Keywords: predation
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