PRECIPITIN TEST FOR EXAMINING PREDATOR–PREY INTERACTIONS IN SOYBEAN FIELDS

Abstract
Precipitin test techniques were utilized for the identification of predators on three lepidopteran pests—Anticarsia gemmatalis Hübner, Heliothis zea (Boddie), and Pseudoplusia includens (Walker). The test was sensitive enough to detect these prey in a whole-body extract of one small predator or from a midgut extract of larger predators. Some cross-reactivity among the prey antigens was found which limited somewhat the applicability of the test. However, test results from field-collected predators indicated the precipitin test is a simple and rapid technique which can be used to evaluate the number of encounters between predators and prey in soybean fields.