Classical and conservation biological control of pest insects within prairie and crop systems

Abstract

Since its introduction in North America, the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae) has become the primary pest of soybean in North America. Despite the impact of predators commonly found in North American soybean fields, frequent pest outbreaks within soybean mandate the use of insecticides to prevent crop injury. Aphid parasitoid wasps such as Binodoxys communis (Gahan) (Hymenoptera: Braconidae) have been shown to be very important in Chinese soybean fields for earlyseason aphid suppression, while parasitoids comprise a small fraction of the North American natural enemy guilds. From 2008 to 2010, we released B. communis at five research farms throughout Iowa to measure the effects of releases on aphid populations, and to describe the capacity of B. communis to effectively locate and colonization aphid host-patches. Paired caged treatments were utilized to provide a baseline comparison of aphid populations over time with and without the addition of B. communis, while open plots allowed for comparison