Potential of the Asian Predator, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), to Control Matsucoccus resinosae Bean and Godwin (Homoptera: Margarodidae) in the United States

Abstract

Studies were conducted in Connecticut from 1983 to 1986 to determine the ease with which the Asian coccinellid, Harmonia axyridis Pallas, can be reared in the laboratory, its ability to control Matsucoccus resinosae Bean and Godwin on Pinus resinosa Aiton, and its ability to overwinter outdoors. The beetle was reared on a diet of pea aphids, Acyrthosiphon pisum (Harris), grown on Vicia faba L. at 27°C and a photoperiod of 16:8 (L:D). Mean development time from oviposition to adult eclosion was 18.6 ± 1.3 d and the average female produced 718.7 ± 93.6 offspring during her adulthood of 83.6 ± 18.7 d. Percentage of predation was high (>80%) if scale-infested pine branches were caged with different densities of H. axyridis larvae when the conspicuous eggs, cysts, and adults of M. resinosae were present. Percentage of predation was significantly lower when scales were predominantly first instars concealed beneath pine bark. Cannibalism was common (>50%) among H. axyridis larvae at all experimental densities. Most of 905 paint-marked adult beetles released uncaged onto infested pines dispersed within the first few days after release. However, before departure, some adults laid eggs on the pines and established a resident population of H. axyridis. Less than 10% of the adult beetles (n = 762) placed in overwintering cages in the field survived from November through March, a period during which weather conditions were normal for Connecticut.