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. The second field trial demonstrated that essential oils of lemon grass and tea tree when combined with kaolin particle films significantly reduce the incidence of tomato spotted wilt. These treatments were as effective as grower standard insecticides. Laboratory experiments indicate that the essential oils and kaolin reduce thrips oviposition. These findings were presented in grower and scientific meetings.

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.

   Optimize use of kaolin and essential oils by determining how they affect thrips and their ability to transmit Tomato spotted wilt virus.

   Refine use of plant essential oils and kaolin in the field based on mechanisms determined in laboratory studies of Objective 2.

   To determine, through Cost Benefit Analysis of each field trial, the management strategies that yields the greatest financial return to the grower.

   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

1. The effectiveness of lemon grass oil and tea tree oil in combination with kaolin were evaluated in field trials against tomato spotted wilt and thrips in tomato. Tea tree (Melaleuca alternifolia) oil and lemon grass (Cymbopogon flexuosus) oil combined with kaolin were as effective as current standard insecticides in controlling tomato spotted wilt, and significantly reduced tomato spotted wilt when compared with the untreated control. As an additional measure, we included another factor in the experimental design – the application of Acibenzolar-S-methyl, a systemic acquired resistance promoter. The addition of Acibenzolar-S-methyl led to further reductions the incidence of tomato spotted wilt in most treatments.

   In laboratory studies, the essential oils of lemongrass and tea tree, and the monoterpenoid geraniol reduced oviposition by the western flowers thrips. This effect was enhanced by the addition of kaolin to the essential oils. Although not highly toxic, these plant essential oils are promising management options for western flower 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.

Impacts and Contributions/Outcomes

Integrated use of lemon grass oil and tea tree oil in combination with kaolin provided as effective control as standard insecticides for thrips-vectored tomato spotted wilt. The use of these essential oils and kaolin is a promising tactic for the management of tomato spotted wilt. These materials are alternatives to the limited suite of standard insecticides available for thrips management in fruiting vegetables.

Collaborators: