SEASONAL OCCURRENCE AND RELATIVE ABUNDANCE OF APHID PREDATORS AND PARASITOIDS ON PUBESCENT POTATO PLANTS

Abstract
During 2 field seasons, Coccinellidae (primarily Coccinella transversoguttata richardsoni, Coleomegilla maculata, Hippodamia convergens, H. tridecimpunctata, and H. glacialis) were the most abundant predators on potato hybrids (Solanum tuberosum × S. berthaultii, F3) with various densities of glandular pubescence. Highly pubescent clones had the highest percentage of predator eggs, while clones with the lowest trichome densities had the highest percentages of immature and adult predators. By comparison, high numbers of aphid parasitoid mummies (primarily Aphidius and Praon spp.) occurred on clones with moderate to high densities of glandular pubescence. During both years, predators and parasitoids were most abundant in late July and August.