In a previous study, three insect growth regulators, diflubenzuron, pyriproxyfen, and fenoxycarb, were shown to reduce the emergence of western flower thrips (Frankliniella occidentalis) from potting medium under experimental conditions. Our objective was to evaluate the impact of potting medium applications of fenoxycarb, diflubenzuron, and pyriproxyfen on western flower thrips and fungus gnats (Bradysia spp.) populations in conventionally grown african violets (Saintpaulia ionantha). In two trials conducted at a university greenhouse and one trial at a commercial flower grower's greenhouse, no reductions were observed in western flower thrips populations. In one university trial, all three insect growth regulators resulted in lower fungus gnat populations. In addition to medium treatment, results from the commercial greenhouse indicated that a pesticide application to the soil under the benches may also be needed to provide management of fungus gnats.
A mail survey was conducted in 2000 to determine awareness and use of integrated pest management (IPM) practices by nurseries in Pennsylvania. Survey participants were randomly selected from the Pennsylvania Dept. of Agriculture, Bureau of Plant Industry, list of certified nurseries. Participants answered questions pertaining to awareness of common practices, frequency that IPM practices were employed, and specifics on monitoring and pest management decision-making processes. Responses were analyzed by Cluster Analysis (SPSS Inc., Chicago), which resulted in the formation of three distinct segments. The segments were labeled “IPM Savvy” (nursery managers who were more likely to employ IPM practices); “Part-time IPMers” (nursery managers who employed some IPM strategies and were interested in future adoption of IPM practices); and “Reluctant IPMers” (nursery managers who were least likely to employ IPM strategies). The “Part-time IPMers” and “Reluctant IPMers” segments represent a substantial part of the industry (51%), who continues to have concerns about the cost, efficacy, and implementation of IPM practices into their businesses. Overall, Pennsylvania growers are aware of IPM practices; however, maintaining permanent records of pests identified and pest management strategies employed remain low. Continued education is warranted to enhance pest monitoring skills and recordkeeping along with demonstrable evidence to the cost effectiveness and marketing benefits that the implementation of IPM practices offer the nursery operators.