COLEOMEGILLA-MACULATA, COCCINELLA-SEPTEMPUNCTATA (COLEOPTERA, COCCINELLIDAE), CHRYSOPERLA-CARNEA (NEUROPTERA, CHRYSOPIDAE), AND MACROCENTRUS-GRANDII (HYMENOPTERA, BRACONIDAE) TRAPPED ON COLORED STICKY TRAPS INCORN HABITATS

Behavioral responses of 4 species of natural enemies to 4 colors were examined by capturing adults on colored sticky cards placed at 2 locat ions (edge and interior) in corn, Zea mays L., fields. Cards were plac ed at 2 heights (1.8 and 0.3 m) in 1993 and in 2 habitats (sweet and f ield corn) in 1994, using a split-split plot design. Natural enemies s tudied included the coccinellids Coleomegilla maculata (DeGeer) and Co ccinella septempunctata L., the chrysopid Chrysoperla carnea (Stephens ), and Macrocentrus grandii Goidanich, a braconid larval parasitoid of Ostrinia nubilalis (Hubner). Compared with red, green, and white card s, yellow cards trapped greater numbers of all natural enemies, except C. carnea, which was trapped equally on cards of all 4 colors. Few si gnificant interactions were observed between the effects of color and those of location and height or habitat, which are perhaps indicative of microhabitat preferences. Captures on cards provided information on abundance of each natural enemy species during different periods in t he summer. It also revealed the pattern of adult flights of M. grandii , which is useful for determining whether its life cycle is synchroniz ed with that of its host. The study suggests that, besides studying be havioral responses, color cards may be useful for monitoring natural e nemy populations.