Development of an IPM Program for Control of Flower-Thrips in Blueberries in Southeastern United States

Project Overview

Project Type: Graduate Student
Funds awarded in 2005: $9,914.00
Projected End Date: 12/31/2006
Grant Recipient: University of Florida
Region: Southern
State: Florida
Graduate Student:
Major Professor:
Dr. Oscar Liburd
University of Florida

Annual Reports


  • Fruits: berries (blueberries)


  • Crop Production: application rate management
  • Education and Training: on-farm/ranch research
  • Pest Management: biological control, biorational pesticides, botanical pesticides, chemical control, economic threshold, field monitoring/scouting, integrated pest management


    Successful management of flower thrips in commercial blueberry plantings is determined by efficient monitoring systems and timely use of control methods. Massive releases of natural enemies as preventive or curative methods did not significantly reduce the population of flower thrips. In the evaluation of reduced risk insecticides, we found that Spinosad was the least toxic insecticide towards Orius insidiosus. However, in field studies, Spinosad was not significantly different to other treatments evaluated for control of thrips. Acetamiprid consistently reduced thrips population in field and laboratory studies but also significantly reduced the number of O. insidiosus in laboratory assays.


    Florida and southern Georgia are the only producers of early-season blueberries (April to May) in the United States, and consequently have a big advantage compared with markets from northern states. Early-season blueberries have prices that can be five to six times higher than regular season blueberries. For instance, although Florida represented only 1.18% of the national production of fresh blueberries for 2003, it collected 8.24% of the money produced from blueberries in the nation. In Florida, the total acreage has increased 21% since 2001 and the overall revenue has increased by almost 6 million dollars in the same period. (NASS and USDA 2004).
    One of the key pests reported on blueberries is flower thrips from the genus Frankliniella. The main species that are repeatedly reported in Florida and southern Georgia are F. bispinosa and F. tritici. In 2003, USDA et al. reported that 40% of the losses in blueberries in Georgia were attributed to flower thrips. Two other species of flower thrips have been reported in blueberries throughout Florida and Southern Georgia. These species are F. occidentalis and F. tritici (Finn 2003). Thrips populations are known to move rapidly into blueberry fields with the help of wind currents and workers. Their life cycles are extremely short, taking only 15 days if environmental conditions are conducive for their growth and development. Their short lifecycles as well as their overlapping generations during the blueberry flowering cycle make this insect a dangerous pest that can reach economic damage levels in a very short period of time.

    Project objectives:

    • To evaluate the interaction between O. insidiosus and A. cucumeris as an alternative to pesticides in maintaining reduced populations of flower-thrips

      To evaluate reduced-risk insecticides and their interaction with Orius sp. (Heteroptera: Anthocoridae) and A. cucumeris, natural enemies of flower thrips

      To compare the effectiveness of reduced-risk insecticides with conventional insecticides for controlling flower-thrips

      To collaborate with growers, extension agents and agricultural consultants to generate and distribute new information on thrips control for early-season blueberries
      available below.

    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.