Integrating plant essential oils and kaolin for the sustainable management of thrips and tomato spotted wilt on tomato

Integrating plant essential oils and kaolin for the sustainable management of thrips and tomato spotted wilt on tomato

Summary

The purpose of this project is to develop environmentally compatible approaches for management of thrips and tomato spotted wilt of tomatoes. A comparison of the effects of kaolin and plant essential oils determined that these materials can significantly reduce feeding by the western flower thrips on tomato. The effects were most pronounced with kaolin. Field trials determined that spray coverage of kaolin should be improved, but it is well retained on plants in the field. Additional research on this topic is being conducted.

Objectives/Performance Targets

1. Compare efficacy of the plant essential oils geraniol, lemongrass oil and tea tree oil, and kaolin to standard insecticides in controlling thrips and tomato spotted wilt in tomatoes.
2. Optimize use of kaolin and essential oils by determining how they affect thrips and their ability to transmit Tomato spotted wilt virus.
3. Refine use of plant essential oils and kaolin in the field based on mechanisms determined in laboratory studies of Objective 2.
4. To determine, through Cost Benefit Analysis of each field trial, the management strategies that yields the greatest financial return to the grower.
5. Demonstrate and disseminate findings to growers, commodity groups, IPM providers, and the agrochemical industry as a means to generate greater interest in developing plant essential oils as commercial products and provide baseline data on the efficacy of plant essential oils and kaolin to control thrips and tomato spotted wilt.

Accomplishments/Milestones

Objective 2. Optimize use of kaolin and essential oils by determining how they affect thrips and their ability to transmit Tomato spotted wilt virus.
In laboratory assays, we have determined that kaolin, by itself and in combination with lemongrass oil, tea tree oil or geraniol, leads to significant reductions in feeding by western flower thrips. Time after application (4 – 24 hours) did not affect feeding reduction. Reductions in feeding are related to the amount of kaolin coverage on plant surfaces. In field trials, over 70% coverage of plant foliage with kaolin can be achieved with a standard CO2 driven backpack sprayer. With no precipitation, kaolin residues remain intact on plant surfaces for at least five days. Further research is being conducted on methods to improve spray coverage. Additional laboratory trials are being conducted to determine if virus transmission is reduced along with the actual amount of thrips feeding.

Objective 3. Refine use of plant essential oils and kaolin in the field based on mechanisms determined in laboratory studies of Objective 2.
Current field trials are being established to determine methods to improve spray coverage of plants in the field.

Objective 4. To determine, through Cost Benefit Analysis of each field trial, the management strategies that yields the greatest financial return to the grower.
Economic analyses will be completed with the conclusion of this year’s demonstration trials.

Objective 5. Demonstrate and disseminate findings to growers, commodity groups, IPM providers, and the agrochemical industry as a means to generate greater interest in developing plant essential oils as commercial products and provide baseline data on the efficacy of plant essential oils and kaolin to control thrips and tomato spotted wilt.
We have presented this research at general public and scientific meetings, including the annual the Gadsden County Tomato Forum, and Entomological Society of America Meetings.

Collaborators: