Analysis of a Biological Control Strategy and its Potential in a Pest Management Program in Florida Cabbage

Analysis of a Biological Control Strategy and its Potential in a Pest Management Program in Florida Cabbage

Summary

Little information exists on whether multiple natural enemies enhance biological control of an insect pest compared with a single natural enemy. A comparison of the natural enemies Cotesia plutellae and Podisus maculiventris used to reduce diamondback moth populations demonstrates that when both natural enemies are present they reduce plant damage and diamondback moth populations additively. In 2002, the parasitoid C. plutellae reduced plant damage and pest abundance significantly more than P. maculiventris. In 2003, there was no difference between C. plutellae plant damage and pest abundance when compared with P. maculiventris. In both seasons the most damage occurred on the intermediate growth stage of cabbage.

Objectives/Performance Targets

• To determine if Cotesia plutellae and Podisus maculiventris have an additive, anatagonistic, or synergistic effect on diamondback moth populations in cabbage.

  To determine how interactions between Cotesia plutellae and Podisus maculiventris influence plant damage caused by the diamondback moth.

Accomplishments/Milestones

A second growing season has been complete and the data from this season have been analyzed. These results were presented in a thesis seminar at Florida A&M University. Organization of the results is currently underway and is being prepared for publication.

Impacts and Contributions/Outcomes

Biological control offers and alternative to the use of insecticides for diamondback moth management. However, information on interactions between predators and parasitoids and how these interactions influence diamondback moth populations and plant damage is limited. An understanding of the joint impact of multiple natural enemies on pest populations is essential to improve biological control as a component of sustainable agriculture. This research will provide such critical information on the interactions between natural enemies of the diamondback moth, and will benefit producers, consumers, and the scientific community by providing additional information regarding safe alternatives to insecticides and sustainable methods of pest management in agriculture.