Source: UNIVERSITY OF FLORIDA submitted to NRP
INTEGRATIVE MANAGEMENT OF WHITEFLIES FOR ORGANIC CUCURBIT PRODUCTION IN THE US SOUTHERN REGION.
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
OTHER GRANTS
Reporting Frequency
Annual
Accession No.
1032874
Grant No.
2024-51300-43092
Cumulative Award Amt.
$1,994,600.00
Proposal No.
2024-03344
Multistate No.
(N/A)
Project Start Date
Sep 1, 2024
Project End Date
Aug 31, 2027
Grant Year
2024
Program Code
[113.A]- Organic Agriculture Research & Extension Initiative
Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611
Performing Department
(N/A)
Non Technical Summary
Research Plan:To develop a nano clay matrix to repeal whiteflies, we will conduct behavioral assays to investigate the contact repellency of different nanoclays against whiteflies. These assays will be conducted in arenas, and the behavior of whiteflies in contact of the different clays will be observed with a camera equipped with a macroscopic lens. Repellency of clays mixed with limonene will be measured with a Y-tube olfactometer assays. To evaluate capacity of nanoclay to carry limonene, headspace volatiles will be collected after 24 hrs, 48 hrs, 1 and 2-week post application and anayzed through a GC-MS system. The decrease of limonene emission from clay-treated plants will be assessed by collecting volatiles from squash plants and compared to the decrease of limonene emitted by a squash plant where limonene will be directly applied to. Antifeedant activities of mineral oil and polygodial will be investigated with feeding assays where the solution will be coated on a watermelon leave. Feeding of whitefly will be measured by visual observation and by the number of stylet sheaths revealed through the McBrinde stain coloration. We will test the effect of coloring nano clay by adding edible pigments to the clay matrix and conducting behavioral assay in laboratory. Reflectance of the clay will be measured and correlated to the whitefly response. Evaluation of limonene and clay against the whitefly and beneficial organisms will be assessed in laboratory. Behavioral and toxicology assay will be conducted to ensure that natural enemies are not disrupted using kaolin and limonene or other essential oils. Field trials will be conducted to assess the combination of nano clay, colored pigment, limonene and antifeedant. There will be four replicates per treatment. The field trial will consist of 8 treatments: 1) untreated control, 2) M-Pede (positive control), 3) kaolin clay + limonene, 3) kaolin clay+ limonene + colored dye, 4) kaolin clay + limonene + antifeedant, 6) kaolin clay + limonene + antifeedant + colored dye, 7) alternative clay + limonene, 8) alternative clay + limonene + antifeedant. The effects of reflective and live mulch will be evaluated during two field trials on squash. The various treatments will be white plastic mulch, reflective plastic mulch, live mulch 1-buckwheat, and live mulch 3 -hairy vetch. Efficacy of row cover will be evaluated during field trials. The following treatments will be evaluated, 1) Season-long row cover with introduction of bumblebees at start of flowering; 2) Season-long row cover but the ends open at start of flowering to enable pollinators access and close the ends 10 days later; 3) Complete removal of row cover at start of flowering; and 4) No row covers (control). We will evaluate the combination of row cover and UV-reflective mulches in field trials. Treatments of row cover, reflective mulch, and OMRI-approved organic insecticides in watermelon or squash crops will be evaluated against the natural populations of whiteflies, predators, and parasitoids. Augmentation biological control in combination with cover crop will be evaluated during a field trial. Cover crops will be planted in spring and fall. The winter cover crop will be cereal rye (Secale cereale L.) and the summer cover crop will be sunn hemp (Crotalaria juncea L.). The experimental design will be a split plot design, with presence or absence of a cover crop as the main effect and the post-cover crop treatment type as the sub effect. Three post-cover crop treatments will be applied to relevant plots. These treatments are 1) no additional treatment (control), 2) intercropping squash with sweet alyssum, and 3) releases of predatory mite Amblyseius swirskii. Each of this technics will be evaluated for their economic sustainability. We will develop detailed regional enterprise budgets using the different alternative production practices investigate in the proposal (mulch, row cover, nanoclay and repellents, augmentative biological control method), and compare them to current organic production practices.Outreach plan: Growers will be engaged from the beginning of the project. Representatives from the main commodity groups affected by whiteflies will be invited to participate in the bi-monthly Zoom calls and annual workshops. Having growers participate in the workshops will ensure that we have identified the key issues relative to organic pest management and that the methods to be developed can be applied in the field and are economically sound.At each workshop, a printed abstract of the presentations will be given to participants, and growers will be informed through the workshop about the current information regarding whitefly management in horticultural crops. Growers will also be able to interact with the different participants, including industry representatives, to help them understand organic pest management. Also, a website will be created to include the current recommendations for organic pest management in horticultural crops. This project will be the first step to developing federal-funded research on organic pest management of whiteflies and aphids in horticultural crops.
Animal Health Component
60%
Research Effort Categories
Basic
20%
Applied
60%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2111429113050%
2151429113040%
2121429113010%
Knowledge Area
212 - Pathogens and Nematodes Affecting Plants; 211 - Insects, Mites, and Other Arthropods Affecting Plants; 215 - Biological Control of Pests Affecting Plants;

Subject Of Investigation
1429 - Cucurbits, other;

Field Of Science
1130 - Entomology and acarology;
Goals / Objectives
1) Organic management of whitefly and their associated viruses with nanoclay mixed with essential oils.2) Evaluation of cultural practices (mulches and row cover) to manage whitefly and whitefly-transmitted viruses in organic cucurbits' production.3) Augmentative biological control and conservation, increase early augmentation of natural enemies. Cover crops may increase the natural enemies, using clover to increase.4) Evaluating the economic sustainability of the newly developed methods compared to traditional whitefly management methods
Project Methods
Research plan:To develop a nano clay matrix to repeal whiteflies, we will conduct behavioral assays to investigate the contact repellency of different nanoclays against whiteflies. These assays will be conducted in arenas, and the behavior of whiteflies in contact of the different clays will be observed with a camera equipped with a macroscopic lens. Repellency of clays mixed with limonene will be measured with a Y-tube olfactometer assays. To evaluate capacity of nanoclay to carry limonene, headspace volatiles will be collected after 24 hrs, 48 hrs, 1 and 2-week post application and anayzed through a GC-MS system. The decrease of limonene emission from clay-treated plants will be assessed by collecting volatiles from squash plants and compared to the decrease of limonene emitted by a squash plant where limonene will be directly applied to. Antifeedant activities of mineral oil and polygodial will be investigated with feeding assays where the solution will be coated on a watermelon leave. Feeding of whitefly will be measured by visual observation and by the number of stylet sheaths revealed through the McBrinde stain coloration. We will test the effect of coloring nano clay by adding edible pigments to the clay matrix and conducting behavioral assay in laboratory. Reflectance of the clay will be measured and correlated to the whitefly response. Evaluation of limonene and clay against the whitefly and beneficial organisms will be assessed in laboratory. Behavioral and toxicology assay will be conducted to ensure that natural enemies are not disrupted using kaolin and limonene or other essential oils. Field trials will be conducted to assess the combination of nano clay, colored pigment, limonene and antifeedant. There will be four replicates per treatment. The field trial will consist of 8 treatments: 1) untreated control, 2) M-Pede (positive control), 3) kaolin clay + limonene, 3) kaolin clay+ limonene + colored dye, 4) kaolin clay + limonene + antifeedant, 6) kaolin clay + limonene + antifeedant + colored dye, 7) alternative clay + limonene, 8) alternative clay + limonene + antifeedant. The effects of reflective and live mulch will be evaluated during two field trials on squash. The various treatments will be white plastic mulch, reflective plastic mulch, live mulch 1-buckwheat, and live mulch 3 -hairy vetch. Efficacy of row cover will be evaluated during field trials. The following treatments will be evaluated, 1) Season-long row cover with introduction of bumblebees at start of flowering; 2) Season-long row cover but the ends open at start of flowering to enable pollinators access and close the ends 10 days later; 3) Complete removal of row cover at start of flowering; and 4) No row covers (control). We will evaluate the combination of row cover and UV-reflective mulches in field trials. Treatments of row cover, reflective mulch, and OMRI-approved organic insecticides in watermelon or squash crops will be evaluated against the natural populations of whiteflies, predators, and parasitoids. Augmentation biological control in combination with cover crop will be evaluated during a field trial. Cover crops will be planted in spring and fall. The winter cover crop will be cereal rye (Secale cereale L.) and the summer cover crop will be sunn hemp (Crotalaria juncea L.). The experimental design will be a split plot design, with presence or absence of a cover crop as the main effect and the post-cover crop treatment type as the sub effect. Three post-cover crop treatments will be applied to relevant plots. These treatments are 1) no additional treatment (control), 2) intercropping squash with sweet alyssum, and 3) releases of predatory mite Amblyseius swirskii. Each of this technics will be evaluated for their economic sustainability. We will develop detailed regional enterprise budgets using the different alternative production practices investigate in the proposal (mulch, row cover, nanoclay and repellents, augmentative biological control method), and compare them to current organic production practices.Outreach plan: Growers will be engaged from the beginning of the project. Representatives from the main commodity groups affected by whiteflies will be invited to participate in the bi-monthly Zoom calls and annual workshops. Having growers participate in the workshops will ensure that we have identified the key issues relative to organic pest management and that the methods to be developed can be applied in the field and are economically sound.At each workshop, a printed abstract of the presentations will be given to participants, and growers will be informed through the workshop about the current information regarding whitefly management in horticultural crops. Growers will also be able to interact with the different participants, including industry representatives, to help them understand organic pest management. Also, a website will be created to include the current recommendations for organic pest management in horticultural crops. This project will be the first step to developing federal-funded research on organic pest management of whiteflies and aphids in horticultural crops.

Progress 09/01/24 to 08/31/25

Outputs
Target Audience:For this first year, the target audience has been graduate students, cucurbit growers, and horticulture Extension agents. The graduate and undergraduate students are getting trained with other laboratory staff and the Co-PIs. For this project, Extension efforts include vegetable growers, extension personnel, industry representatives, and other academic researchers. Co-PIs regularly consult with these parties to provide and discuss the latest information on whitefly management. Co-PIs participate in or organize a field day to disseminate the information to growers and stakeholders. The graduate students also have responsibilities in disseminating the information related to the project and whitefly pest management to the public through outreach events, including school tours and community events. Changes/Problems:The initial international student hired by Dr Martini to work on this project couldn't come due to the visa ban applied to her home country (Myanmar). This delayed considerably the development of the project, and we are preparing a non-cost Extension to have more time to achieve our objectives. What opportunities for training and professional development has the project provided?So far, training has been provided to the graduate students on the practice of cover cropping and nanoclay use. We are working on a field day to be organized in Citra, FL , which is planned to demonstrate this cover crop and nanoclay research, as well as to extend information on cover crops as a pest management tool to members of the organic agricultural community. How have the results been disseminated to communities of interest?Currently, mostly through scientific conferences, including the Entomological Society of America Annual and Branch Meetings. What do you plan to do during the next reporting period to accomplish the goals?During the next reporting period, we plan to complete the analysis of data from the recent spring 2025 field experiment. The fall 2025 and spring 2026 field trials are also expected to be concluded, and data from these experiments should be partially or fully analyzed within the next reporting cycle. Findings from this research will be shared at planned field day events (such as a field day planned for September 2025) and academic conferences (Entomological Society of America Southeastern Branch Annual Meeting). We expect to have the screening of the different nanoclays achieved during the year, as well as the evaluation of the antifeedant on whitefly behavior.

Impacts
What was accomplished under these goals? In Dr. Martini's Lab, we purchased a Keyence high-definition microscope to help us monitor the behavior of whiteflies when in contact with the nanoclay. Dr. Martini started the evaluation of the different nano clay (objective 1). We developed a two-choice test for whitefly to evaluate its response to different nanoclays. We also established a new method to measure the reflectance of mulch over time. In Dr. Liburd's Lab, a spring organic squash field trial was conducted to evaluate winter rye as a cover crop for managing several cucurbit pests, concluding in July 2025. The collected data from this experiment is in the process of being analyzed. A summer cover crop (sorghum-sudangrass/sudex) was planted in June for an upcoming Fall 2025 field experiment. Significant progress has been made towards evaluating the potential of certain cover crops as a pest management tool. Although data have not been formally analyzed, preliminary results indicate that the winter rye may have led to a significant decline in aphid populations. Additional field trials in 2025 and 2026 need to be conducted to draw comprehensive conclusions on winter rye and other cover crops being tested. Dr. Qureshi tested the efficiency of MBI-306, a biopesticide derived from the soil-dwelling bacterium Burkholderia rinojensis, a naturally occurring microorganism. This product is intended for use in organic and sustainable agriculture production systems. For the purpose of the experiment, the efficiency of MBI-306 was compared to conventional insecticides. In Spring 2025, it was tested in three management programs for whitefly Bemisia tabaci on zucchini squash: 1) No spray, 2) MBI 306 sprays, 2) MBI 306 and two conventional insecticide sprays, and 3) a standard program including sprays of three conventional insecticides. The program using MBI 306 alone provided a significant reduction in adult whitefly numbers compared to the drench alone program and was not significantly different from the program using sprays of MBI 306 and two conventional insecticides. It was only for one to two weeks that the standard program using spray applications of three conventional insecticides provided significantly more reductions than programs of MBI 306 alone or with conventional insecticides. The number of whitefly adults per leaf averaged 23.35, 12.18, 13.21, and 9.66 in the treatment programs 1, 2, 3, and 4, respectively. The effects of treatment programs on eggs were not consistent but followed a similar trend in reducing whitefly populations as observed against adults, with a per square inch average of 31.96, 27.38, 20.77, and 13.08 eggs in the treatment programs 1, 2, 3, and 4, respectively. Effects on nymphs that developed to maturity were more consistent, and most reduction was seen in program 4, followed by 3, 2, and 1, and an average of 8, 20, 40, and 80 nymphs. In Clemson, both a PhD student and a research technician were recruited in Dr. Bilbo's lab and began working on this project. The first field experiment was completed, and preparation is underway for the continuing field experiments related to Objective 3. Initial analyses from the spring field trial are underway, and findings were presented at Extension events and Scientific meetings. Finally, Dr. Solis presented the steps needed for the economic evaluation of the developed methods. He is working with different PIs for the economic assessment of the different tools developed within the grant.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: Bilbo TR. February 2025. BioSolutions Conference & Expo, Fresno, CA. Advancing Biocontrol: Practical Considerations for Vegetable and Strawberry Arthropod Pests
  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: Bilbo, TR. February 2025. Invited seminar speaker, USDA Agricultural Research Service, Salinas, CA. Prospects and challenges for biological control of arthropod pests
  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: Bilbo TR and S Parajuli. June 2025. Charleston County Master Gardener tour of Clemsons Coastal REC. Can cover crops be used to enhance biological control in organic vegetables?
  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: Bilbo TR. February 2025. Spider mites in strawberries; Biocontrol options in Brassicas. Midland Vegetable Meeting (Pelion, SC. Presented virtually)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: Bilbo TR. February 2025. Biological control in South Carolina Brassica crops. Charleston County Pre-plant Vegetable Growers Meeting (Charleston, SC)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2025 Citation: Martini X., Paris, T. Symposium. New approaches to control Bemisia tabaci with nanoclays and visual lures. Southeastern Branch of the Entomological Society of America Meeting. Baton Rouge, LA. March 9-12, 2025.