Enhancing Biological Control With Insectary Plantings

Project Overview

Project Type: Research and Education
Funds awarded in 1999: $83,929.00
Projected End Date: 12/31/2003
Matching Non-Federal Funds: $13,651.00
Region: Western
State: Oregon
Principal Investigator:
John Luna
Oregon State University

Annual Reports


  • Vegetables: broccoli


  • Crop Production: intercropping
  • Pest Management: biological control


    We have conducted on-farm experiments in Oregon broccoli production systems to explore the potential of using insectary flowers to enhance the biological control of cabbage aphid (Brevicoryne brassicae) by naturally-occurring predacious hoverflies. Our conclusions include:
    Insectary plantings increase abundance of hoverfly predator eggs in broccoli fields, however no suppression of cabbage aphid was demonstrated.
    Both pest and beneficial insect species utilize nectar and pollen from the insectary plants we tested. The use of certain insectary plants may actually increase pest problems. Using beneficial insectary plantings for conservation biological control must consider impacts on pests, beneficials, and hyperparasitoids across all crops occurring within the system.
    Selected insectary plants exhibit preferential attractiveness among entomophagous and pest species.
    Biological pest control efforts need to be conducted at the species level of ecological inquiry, with considerable error possible from decisions made at the family level of taxonomic groupings.
    Appropriate scale of experimental design needs to incorporate dispersal behaviors of target species and natural enemies.
    Oviposition (egg-laying) behavior of adult entomophagous species may be key factor limiting effective biological control

    Project objectives:

    1. To evaluate the relative attractiveness of selected insectary plants to entomophagous arthropods and key insect pests
    2. To evaluate the potential of using beneficial insectary plants to enhance biological control of specific insect pests in broccoli production systems, including: the cabbage aphid complex and the worm complex.
    3. To develop a multi-faceted educational program for growers and agricultural professionals on integrating beneficial insectary plantings into various kinds of farming operations to enhance biological pest control.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.