Toward the Development of a Push-Pull Strategy to Control Whiteflies in Florida Vegetables

View the project final report

Commodities

• Vegetables: tomatoes

Practices

• Pest Management: botanical pesticides, chemical control, cultural control, integrated pest management

Sweetpotato whitefly, Bemisia tabaci, is a major economic pest of row crop vegetables causing widespread feeding damage and vectoring many viruses, including tomato yellow leaf curl virus (TYLCV), which leads to considerable yield loss. Growers are facing increasing challenges in controlling B. tabaci as populations during major growing seasons have become increasingly unpredictable and resistant to conventional insecticides. In an effort to develop a more sustainable integrated pest management program, alternative methods for controlling B. tabaci are being explored that take advantage of the whitefly's natural host seeking behaviors.

Since visual stimuli play a dominant role in host searching behavior, implementing visual traps that display the most attractive wavelengths in the visual spectrum shows great potential in reducing B. tabaci infestations. In addition, many natural repellents including kaolin clay can repel whiteflies visually or mask the attractive volatiles produced by their vegetable host. Preliminary studies have already shown that kaolin clay has proven to act as a moderately successful, natural repellent of B. tabaci adults. However, little to no research has investigated the efficacy of kaolin in combination with other natural repellents and as part of a completed IPM system.

This study will highlight the potential for implementing a "push/pull" system utilizing a combination of natural repellents and visual traps to keep whiteflies below the economic threshold in row crop vegetable. Using this system will reduce the need to use conventional insecticides and lower the associated negative impacts on environmental and human health while increasing benefits for growers.

• Determine how visual attractiveness in TYLCV-infected tomato changes whitefly behavior.
• Determine how B. tabaci behavior is influenced by olfactory cues in healthy tomato vs. TYLCV-infected tomato and compare how this behavior changes when combined with the most attractive visual cues found in Objective 1.
• Determine the efficacy of several natural repellents on whitefly settling in tomato under greenhouse conditions.
• Conduct field trials to test the efficacy of kaolin clay as a natural repellent for B. tabaci nymphs and adults when applied alone and in combination with several botanic oils.