The mutualistic relationships that occur between myrmecophilous aphids and ants are based on the rich food supply that honeydew represents for ants and on the protection they provide against aphid natural enemies. While aphid predators and parasitoids actively forage for oviposition sites by using aphid semiochemicals, scouts of aphid-tending ant species would also benefit from locating honeyde...

Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), reached damaging levels in 2003 and 2005 in soybean, Glycine max (L.) Merrill, in most northern U.S. states and Canadian provinces, and it has become one of the most important pests of soybean throughout the North Central region. A common experimental protocol was adopted by participants in six states who provided data from 19 yiel...

We used multiple regression modeling to investigate the numerical response by the predatory insectsHippodamia convergensGuérin-Méneville,H. parenthesis (Say), and C. septempunctataL. (Coleoptera: Coccinellidae),Chrysoperla plorabunda (Fitch) (Neuroptera: Chrysopidae), and Nabis americoferus Carayon (Hemiptera: Nabidae) to aphids during 5 yr in three geographically separated alfalfa Þelds in eas...

Aggregation of conspecific predators sharing a common prey, influences their bodyweights. We investigated the influence intraspecific competition adult ladybirds Coccinella transversalis Fabricius on bodyweight feeding rusty plum aphid, Hysteroneura setariae (Thomas). Adult males and females consumed significantly greater number aphids with increase in predator-density, however, aphid-consumpti...

In the north central United States, populations of the exotic soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), are highly variable across space, complicating effective aphid management. In this study we examined relationships of plant nutrients, landscape structure, and natural enemies with soybean aphid abundance across Iowa, Michigan, Minnesota, and Wisconsin, representing the ...

Cotton varieties expressing Cry proteins derived from the soil bacterium Bacillus thuringiensis (Bt) are grown worldwide for the management of pest Lepidoptera. To prevent non-target pest outbreaks and to retain the biological control function provided by predators and parasitoids, the potential risk that Bt crops may pose to non-target arthropods is addressed prior to their commercialization. ...

Global warming is generally predicted to increase the intensity of herbivore pressure on plants. Support for this prediction often comes from short-term studies, or studies conducted in controlled laboratory settings. We examined the effect of long-term experimental warming on an aphid-sagebrush interaction (Obtusicauda coweni and Artemisia tridentata) in natural field plots in the Rocky Mounta...

This paper uses a methodology based in Fuzzy Sets Theory in order to describe the interaction between the prey, Aphis glycines (Hemiptera: Aphididae)—the soybean aphid, and its predator, Orius insidiosus (Hemiptera: Anthocoridae) and to propose a biological control to soybean aphid. Economic thresholds were already developed for this pest. The model includes biotic (predator) and abiotic (tempe...

As part of my research on the mass production and augmentative release of ladybirds, I reviewed the primary research literature to test the prediction that ladybirds are effective aphid predators in greenhouses. Aphid population reduction exceeded 50% in most studies and ladybird release rates usually did not correlate with aphid reduction. The ratio of aphid reduction/release rate was slightly...

Insectivorous birds and ants co-occur in most terrestrial communities, and theory predicts that emergent properties (i.e., nonadditive effects) can determine their combined influence on arthropods and plants. In a three-year factorial experiment, I investigated whether the effects of birds on pine and its arthropods differed based on the presence of ants that were predators of most arthropods, ...