Project Summary:

The SARE (Sustainable Agriculture Research and Education) Program recognizes the value and importance of on-farm, producer experience in developing solutions to agricultural problems. The projects are developed, coordinated and conducted by growers or grower organizations. The SARE Program's mandate is to promote sustainable agricultural systems that enhance environmental quality, make the most efficient use of non-renewable resources and integrate natural biological cycles and controls while sustaining the economic viability of the farming operation.

For this Producer/SARE project, GCC is working with a grower/cooperator who is trying to control thrips in his pepper production system by augmenting predator numbers using companion plants (sunflower). Several species of thrips (most notably Frankliniella occidentalis and Thrips palmi) result in tremendous problems in vegetables. In peppers, thrips feed on the developing fruit and on the foliage. The damage caused during fruit feeding render the fruit unmarketable. Chemical control is often difficult because of development of resistance. Many chemical applications are then made to try and control this pest, to little avail. The frequent applications of chemicals for thrips control result in a reduction or an elimination of natural enemies that help control other pests as well as thrips.

Orius insidiosus, the insidious flowerbug, is the major predator of thrips in Florida. This small black and white bug is excellent at finding and preying on thrips in pepper flowers. To augment Orius numbers, the grower planted sunflowers (var. Santa Fe) along his irrigation ditches. The sunflowers provide an excellent alternative habitat for Orius by supplying pollen, nectar and alternative prey.

We found that Orius adults will move rapidly from the sunflowers into the pepper field (within 1 week) in large numbers when thrips numbers begin to reach 3-5 /pepper flower. Adult Orius populations can increase by as much as 10x in the field over that one-week period. Once the thrips population drops in the pepper field (going from 25 thrips/flower to 2-3/flower), Orius move back onto the sunflowers. This scenario is then repeated throughout the season as thrips populations fluctuate. These predatory bugs also move greater distances away from the sunflowers into the pepper field in search of thrips than previously thought possible. Rather than moving out only 3 - 6 rows of peppers into the field, we found Orius moving out 28 - 40 rows. This could mean that one row of sunflower may supply enough Orius to control a moderate to high population of thrips in an 8 - 10 acre area. To our knowledge, these results are the first to demonstrate how a companion plant (sunflower) can increase a predator to control a pest throughout the season and in such large areas of a field. We will conduct another season of research to discern the efficacy of using the sunflowers and Orius to control thrips in south Florida peppers.