Mixing novel microbial and entomopathogenic fungal strains with robotic sprayers for effective whiteflies and thrips control in high tunnel tomatoes

Commodities

Practices

Advancing sustainable commercial tomato production in the Southern region required extensive research on high-tunnel production systems and integrated pest management to promote productivity and fruit quality. The lower costs of establishing a low/high tunnel tomato production system relative to greenhouses and indoor structures make it an excellent target for research to advance tomato production in the south. Tomatoes are among the most important specialty crops produced in the US, with an average area of 109,669 hectares under open-field cultivation in the 2022 growing season and a market value of $1.8 bn. Florida planted 9,712 hectares of tomatoes in 2024, valued at $330 million, making it a major specialty crop grown in the state. Texas produced ~849 hectares of tomatoes, but the exact dollar value is not reported. Tomato is a major crop in controlled environment agriculture (CEA), generating approximately $470 million in revenue and accounting for about 35% of total U.S. tomato production. However, while high tunnels could provide optimum conditions for tomato growth, they also favor the population growth of major insect pests that threaten CEA crops. Pests and their associated viral diseases continue to pose significant challenges with the IUNU's State of CEA 2023 Industry Report estimating roughly 12% revenue losses in CEA tomato production. Conventional pest control methods threaten agroecosystem by adversely affecting ecosystem services and human health.

Sweet potato whiteflies (SWF) and Western flower thrips (WFT) are two of the most challenging tomato pests, transmitting tomato yellow leaf curl virus and resistance-breaking tomato spotted wilt virus, causing substantial yield losses nationwide. The rapid evolution of insecticide resistance in these pests has rendered chemical insecticides unreliable as long-term solutions, renewing interest in ecological-based management strategies. To address this challenge, we have assembled a multidisciplinary team to apply a system-based approach to developing an optimized IPM program for achieving chemical-free tomato production in high tunnel systems (i.e., also applicable to other CEA systems), thereby ensuring long-term agroecosystem health and food security. Our research objectives align with Southern SARE's priorities, aiming to develop sustainable tomato production practices in the Southern region that integrate: Biocontrol using entomopathogenic nematode (EPN) symbiont bacteria and entomopathogenic fungi (EPF) compatible with generalist predators and an AI-assisted robotic sprayer for precise, data-driven product delivery. These robotic tools leverage real-time data and machine learning to enable targeted applications, significantly reducing product volume and labor associated with conventional blanket spraying. By merging engineering innovations with applied agricultural sciences, this project directly addresses major pest management challenges in CEA tomatoes. We will conduct on-farm trials in three locations (farms) to validate our results. In addition, we will organize in-person field days or conferences to educate growers interested in growing tomatoes in high tunnels. PI-Kheirodin is hosting an annual CEA IPM field day at Texas A&M Dallas Center, which will be an excellent platform to disseminate the project's findings.

Objective 1. Evaluate the efficacy of entomopathogenic fungi (EPF) and entomopathogenic nematode (EPN)-associated bacteria for control of sweetpotato whitefly (SWF) and western flower thrips (WFT) on tomato.

We will assess the efficacy of several commercially available EPFs alongside novel locally isolated EPF strains and EPN-associated bacterial strains provided by the University of Florida (Co-PI Hajihassani). Experiments will be conducted using tomato plants under both controlled laboratory conditions and in high-tunnel systems to evaluate their effectiveness in suppressing SWF and WFT populations. We hypothesize that selected microbial strains will significantly reduce pest populations under both settings, with performance varying by strain and different conditions. This objective will identify the most effective microbial candidates for managing these key insect vector pests and provide the foundation for their integration into an ecologically based, systems-oriented IPM program that reduces reliance on chemical insecticides.

Obj 2) Determine the compatibility of EPF and EPN-associated bacteria with SWF and WFT generalist predators to find biocontrol compatible strains.

Based on recent findings and our preliminary data, our working hypothesis is that careful selection of compatible products can synergize with biological control services to improve ecological-based SWF and WFT control without chemical use. This objective addresses a key limitation in sustainable pest management: incompatibility between microbial products and natural enemies. We hypothesize that careful selection of microbial agents will enable synergistic interactions with natural enemies, enhancing pest suppression without disrupting biological control. Compatibility will be assessed through predator survival, behavior, and predation efficiency following exposure to candidate products, ensuring a systems-based evaluation of multitrophic interactions. This work supports SSARE goals by reducing reliance on chemical insecticides (environmental stewardship), improving pest control efficiency and lowering input costs (economic viability), and minimizing pesticide exposure for farm workers (quality of life). The outcome will be a practical decision-support guide for growers, identifying compatible microbial and biological control combinations to improve integrated pest management of whiteflies and thrips in high tunnels and controlled-environment systems, and with implications for other growing settings such as field production.

Obj 3) Developing physics-based simulation for virtual robot testing and optimization for targeted product application.

The objective aims to develop a high‑fidelity, physics‑based simulation environment for virtual testing, design optimization, and AI training for targeted pest management. The simulation will replicate realistic tomato plant structures, biomechanical behavior, and pest distributions, enabling safe and repeatable evaluation of robotic perception, navigation, and precision application strategies. By integrating sensor emulation and physics‑enabled plant models, this virtual platform will support optimization of pest detection algorithms, end‑effector positioning, canopy access, and pest targeting while minimizing plant damage and non‑target exposure. This objective will reduce costly hardware trial‑and‑error, accelerate system refinement, and improve the robustness and field readiness of precision biocontrol application technologies across different crop and canopy conditions.

Obj 4) Design, Integration, and Validation of a Precision Robotic System for IPM approach efficacy in SWF and WFT control in high tunnel tomatoes.

Building on Co-PI Zahid's previous research, preliminary data, and recent advances in precision agriculture, we hypothesize that an AI-assisted robotic sprayer can significantly improve pest management outcomes by optimizing product delivery. Specifically, we expect this system to reduce the total volume of products applied by enabling targeted, data-driven applications based on real-time pest detection. Thus, this objective focuses on the design, integration, and evaluation of a biocontrol‑centered robotic spraying system for precision pest management. This objective will integrate pest detection, targeted application hardware, and canopy‑aware manipulation into a unified robotic platform. Local field data and synthetic data generated from simulation will be used to train and validate vision‑based pest detection models. A custom end‑effector will be designed to enable precise under‑leaf delivery of microbial treatments while minimizing plant disturbance and non‑target exposure. The complete system will be evaluated in high tunnel experiments by comparing targeted robotic application against conventional blanket spraying, assessing pest suppression efficacy, input‑use efficiency, and overall precision in managing SWF and WFT populations. Overall, this objective aims to demonstrate that AI-assisted precision applications can improve the compatibility between pest control interventions and biological control, leading to more sustainable management of whiteflies and thrips in controlled-environment systems.

Obj 5) Extensive extension program (e.g., field days, on-farm trials, webinars) to disseminate the results of this project with farmers and educate growers at all levels of experience through on-farm trials and education programs.

We will develop and deliver a comprehensive extension program, including field days, on-farm trials, workshops, and webinars, to share project outcomes with growers across the Southern region. On-farm trials will serve as demonstration sites to showcase the effectiveness and practicality of integrating biological control, microbial products, and AI-assisted precision technologies under real production conditions. PI Kheirodin's existing extension network will be central to these efforts. Established field day programs at Texas A&M AgriLife Research and Extension Center at Dallas and Texas A&M AgriLife Research and Extension Center at Uvalde will serve as key demonstration and engagement platforms. In addition, his network of tomato growers across Texas will facilitate on-farm trials, rapid dissemination of findings, and direct producer feedback. Pre- and post-event surveys, along with a 6-month follow-up survey, will be implemented to evaluate knowledge gain, monitor adoption, and identify grower concerns to improve adoption outcomes. These activities will target growers at all experience levels, providing hands-on training and practical decision-support tools. This objective supports SSARE goals by accelerating the adoption of practices that reduce chemical inputs, improve profitability, and enhance environmental and worker health.