Enhancement, Implementation - Evaluation of Biologically Based Pest Management Tactic for Three Key Pests in Production Nurseries

Enhancement, Implementation - Evaluation of Biologically Based Pest Management Tactic for Three Key Pests in Production Nurseries

Summary

The four phases of the proposed four-year project are: 1) research to evaluate the efficacy of, and refine techniques for using a biologically based pest management tactic, 2) a demonstration phase to integrate this and other tactics into a biologically based IPM program in commercial nurseries and evaluate their applicability (efficacy, ease of use, and profitability), 3) an education phase to extend results to end users and increase the likelihood of adoption of these biologically based tactics and IPM, and 4) perform an impact assessment to determine and document changes in practice, knowledge, and attitudes of beneficiaries. In addition, a committee of project beneficiaries (IPM scouts, nursery managers, and demonstration cooperators) will be formed from which feedback, in the form of discussions and e-mails with project investigators, will be solicited at key points in the project to assure the project stays on track.

Objectives/Performance Targets

1. To refine and evaluate biologically based pest management tactics and habitat manipulations for their feasibility (effectiveness, ease of use, and profitability) in increasing generalist predator populations, with a concomitant reduction in pest populations (research).

2. We predict that three of the four commercial nurseries and all three of the IPM scouts engaged in the demonstration phase of the project will continue to implement biologically based pest management tactics over chemical tactics (demonstration).

3. We predict that 100 of the 250 nurseries in Maryland will increase their implementation of biologically based tactics, and that 25 of the 36 participating extension personnel in the northeast region will increase the number of times they train on biologically based control tactics for one year after participating in SARE education programs compared to the previous year (education and evaluation).

Accomplishments/Milestones

For 2002, our goal was to develop and evaluate biologically based pest management tactics by conducting an applied research project(performance target 1). More specifically, we wished to determine: 1) the effect of adding wood mulch to nursery beds with container plants of Cotoneaster dammeri compared to weed cloth beds, and 2) the effect of plant and pot position (above ground, as compared to pot-in-pot) on arthropod (herbivore, alternate prey, natural enemy) taxa and abundance and herbivore (Hawthorn lace bug and black vine weevil) survival. To date, we have developed the research protocol and set up and conducted the experiments. We are in the process of identifying arthropod samples taken over several dates throughout the season to family and trophic group (approxumately five of nine dates complete). We have analyzed and interpreted data on the impact of the habitat manipulations on herbivore (Hawthorn lace bug nymphs and black vine weevil eggs and larvae) survival.

Impacts and Contributions/Outcomes

In comparing the taxa and abundance of alternate prey and natural enemies in plant containers between mulch and weed cloth beds and pot position (pot-in-pot vs. above-ground pots), we found no effect of mulch. However, the sum of natural enemies was greater in pot-in-pot containers than in above-ground containers. Individual predators, such as ants, rove beetles, ground beetles, spiders, and a parasitoid (Scelionidae) were found to be more abundant within pot-in-pot containers than in containers above ground. Arthropods such as Collembola, which serve as alternative prey for beneficial insects, were again more common in the pot-in-pot position than the containers above ground.

We found that the mulch and no-mulch treatments rarely had an effect or a reduction in the survival of Hawthorn lace bug nymphs or the eggs and larvae of black vine weevils. We also found that the pot position had no consistent effect on hawthorn lace bug survival. However, pot position did significantly affect black vine weevil egg and larvae survival. In all experiments, predation of eggs and larvae was higher in containers placed pot-in-pot versus above ground.

Practical implications: With the results of this study, we can make recommendations to nursery growers on plant production procedures that would favor natural enemies and reduce pest outbreaks, such as the use of the pot-in-pot technique to reduce soil dwelling herbivores.

Collaborators: