Monitoring the Efficacy of Biological Control Agent Ladybird Beetles to Manage Scale Insects

Abstract

There are multiple methods in which pests, or nuisance species, can be removed from infected target plants. One approach is via biological control, which is when a living organism is used to control or manage a pest, parasite or other species. Biological control was applied during this experiment involving a fern, ladybird beetles and scale insect. Crown fern (Aglaomorpha coronans) located in the greenhouse on SUNY Plattsburgh campus is infected with scale insects. Fourteen of its fronds are contaminated with scale insects. This fern was exposed to the Harlequin ladybird beetle (Harmonia axyridis succinea) to test their merit as a biocontrol agent. The fern was place in a netted area with dimensions of 1.3m x 1.2m x 0.9m in the greenhouse at SUNY Plattsburgh. Population counts of scale insects were taken weekly and ladybird beetles were added as harvested from local homes. Results demonstrate that starting with week 1, the addition of predatory beetles resulted in a dramatic decline in pest scale insects. These predators are effective biological control agents for brown scale insects, but care must be taken as they are invasive species that have disrupted the native Coccinellid complex.