Predictably Unpredictable

An unusually mild winter followed by a wet spring made last year one of the worst in a decade for Pennsylvania soybean growers. It wasn't the soybeans that were the problem; it was the slugs. The pests survived the warm winter to lay a second round of eggs, and twice as many slugs hatched in the spring of 2024 as the year before. The slugs ate so many seedlings that some growers had to replant three times.

"You'll see the forecast, and it's weather we aren't used to," said Paul Esker, professor of epidemiology and field crop pathology in the College of Agricultural Sciences. "Uncertainty has increasingly become a bigger part of farming. It's just the world we've been dealing with for the last several years."

As climate change accelerates and threats from pests and diseases intensify, Esker is part of a growing cohort of Penn State researchers developing innovative solutions to help crops not only survive but also thrive. Through breakthroughs in biotechnology, modeling, and precision agriculture, scientists are designing tools and systems that build plant resilience from the ground up.

Paul Esker, professor of epidemiology and field crop pathology in the College of Agricultural Sciences, developed the Open Crop Manager, a web-based platform and mobile app that can calculate how diseases and pests could impact crop yields.

"As a land-grant university, our mission is to take on the challenges growers face every day and deliver real-world solutions to better serve the people of Pennsylvania," said Troy Ott, dean of the College of Agricultural Sciences. "Our researchers are developing technologies to help farmers increase yields, protect our natural resources, and stay resilient in a changing world."

Battling Crop Threats with Data

As farmers face increasingly unpredictable growing conditions, Esker has pulled together an interdisciplinary team of experts to tackle this existential problem of uncertainty. The team developed the Open Crop Manager, a web-based platform and mobile app that enables farmers, consultants, and extension educators to document and scout crop conditions as well as make field observations with spatial and temporal precision. The data then are fed into machine learning and predictive modeling to calculate how diseases and pests could impact crop yields.

The complex models analyze agricultural data across multiple states, helping farmers make more informed decisions about crop management, pest control, and resource allocation, Esker said. The platform is free, supported by commodity board funding. It is designed to help farmers while also providing researchers and policymakers with large-scale insights into agricultural patterns and potential risks to the nation's food supply.

"Our idea is to empower farmers by getting their data back in their hands," said Esker, who also serves as one of the college's inaugural Land Grant Research Impact Fellows. "We are providing insights that can help farmers make more informed agricultural decisions—and that ultimately can improve outcomes."

Through a combination of scout visits and farmer-generated logs, the team has collected approximately 13,000 unique reports across 10 states over three years. The reports offer a comprehensive record of crop conditions over time, providing valuable information about weeds, pests, diseases, and wildlife damage from larger animals such as deer and groundhogs.

"Farmers can see this aggregated data from multiple regions, helping them compare their practices and conditions with others," Esker said. "We're learning from farmers what works effectively and then building out the technology to better support them. A lot of this is driven by us listening to farmers and then thinking through how we can best help them by providing data-driven insights."

He added that the Open Crop Manager can help farmers assess their return on investment for seed treatments, herbicides, insecticides, and fungicides, which ultimately will affect their bottom line and can reduce unnecessary pesticide use. The models overlay satellite imagery and weather forecasts to predict changes in agricultural conditions, Esker explained, which means farmers can use the platform to optimize crop production as well as receive early warnings for potential issues.

"In some Pennsylvania valleys, farmers might share only one piece of ground rig equipment, so quick and efficient information sharing becomes crucial," he said. "The Open Crop Manager allows farmers to rapidly share and access agricultural insights to respond more effectively to local challenges. Essentially, the platform transforms local, fragmented knowledge into comprehensive, actionable information for farmers."

Harnessing Natural Defenses

For Sara Hermann, Tombros Early Career Professor and assistant professor of arthropod ecology and trophic interactions, developing advanced agricultural technology requires looking back to the very evolution of predator-prey relationships.

Her lab in the College of Agricultural Sciences has developed an innovative new pest management technology that uses the odor of ladybugs to deter aphids, which are agricultural pests that weaken plants by sucking their sap and spreading disease. By collecting and analyzing the volatile compounds produced by ladybugs, Hermann created what she playfully calls the "eau de ladybug" strategy. When aphids detect this scent, they change their behavior, she explained, reproducing less, feeding less, and avoiding plants where the odor is present, which helps protect crops without using pesticides.

"It's like a human walking up to a building smelling smoke and thinking, 'Hmm, maybe this isn't a good place for me to go. This seems dangerous,' so we change our behavior," Hermann said. "The aphids do something similar. They smell these lady beetles, and they decide that maybe it is not a place where they should be going."

In Hermann's system, biocontrol involves using the natural predator-prey relationship between ladybugs and aphids to growers' advantage. Instead of physically introducing ladybugs as biocontrol, she disperses lady beetle odors to manipulate aphid behavior. This approach leverages natural ecological interactions to manage pest populations without chemical pesticides, providing a sustainable alternative for pest management, she said.

"I'm in a very small subfield of insect ecology that's doing this kind of work where we're looking at how we might harness the fear of being eaten or the threat of predation of these pest insects for pest management," Hermann said. "We're finding fear causes all kinds of changes in behavior and physiology that are beneficial to the plant that aphids are feeding on."

So far, Hermann's team has focused on the plant genus Brassica, which includes popular vegetables such as broccoli, cauliflower, collards, cabbage, kale, and Brussels sprouts. Their research has shown that the "eau de ladybug" strategy can reduce aphid populations by 50% or more on plants in that genus.

"The results are very promising, but aphids are global pests on hundreds of crops," Hermann said. "In theory, this work will be tested across different systems to see if it's applicable on other plants as well."

Hermann has filed a full U.S. patent for the technology and is in field-trial stages within her lab. She has begun reaching out to potential industry partners, including an initial meeting with a multinational pesticide company and some specialized chemical ecology companies that might be interested in developing the product for widespread use.

She is particularly targeting smaller-scale, diversified farms and home gardeners as the initial market, with ongoing research to validate the technology's effectiveness across larger crop systems. She's hoping that one day the product could be sold through garden centers, agricultural supply stores, and potentially big-box retailers, appealing to consumers interested in sustainable gardening practices and reducing chemical pesticide use.

"It could be marketed as an eco-friendly, pesticide-free pest management solution, because that's exactly what it is," Hermann said.

Engineering Smart Solutions

It's one thing to develop technology, but it's an entirely different challenge to have that technology adopted on working farms. That's where John Wallace comes in. Wallace is an associate professor of weed science and leads research on integrating precision technologies into weed management strategies.

He recently partnered with John Deere through a Pennsylvania Soybean Board grant to study the company's new See & Spray technology, which enables targeted herbicide application only where weeds are present, using computer vision and machine learning to target and spray weeds in a standing corn or soybean crop. Early results from his research indicate the technology may allow for up to 70 percent reduction in herbicide use per field.

"We now have the ability to apply herbicides only where weeds are present within the field," Wallace said. "This can help a grower to meet crop and weed management objectives while potentially using significantly less herbicide. There's an environmental benefit to reducing pesticide loads—we reduce the risk of surface and subsurface runoff—and it also comes with the economic benefit to the producer by reducing their pesticide bill."

The research collaboration with John Deere involves partnering with early adopters of the technology, collecting data using field surveys and quantifying how the return on investment changes under different management scenarios. Currently, about 20 producers in Pennsylvania are using the technology, and Wallace's team is working to understand its benefits and limitations in precision agriculture. The researchers aim to shorten the learning curve for early adopters and inform other producers, Wallace said.

John Wallace, associate professor of weed science, leads research on integrating precision technologies into weed management strategies. His work enables targeted control methods that reduce herbicide use while supporting long-term soil and crop health.

"We're providing a linkage between the early adopters and producers that haven't yet experienced or know about the technology," he said. "Industry has introduced this technology, and our job is to use survey methods to start to quantify what that benefit is, what the tradeoffs are, what the limitations are, in an effort to help farmers make the right decision on whether this technology is a good fit for their production system."

For Long He, associate professor of agricultural and biological engineering, the adoption and development of agricultural technology is particularly collaborative because farmers are active participants throughout the process. Rather than serving as recipients of new technology, the farmers that He works with are an equal part of the engineering team.

He develops robotic systems and sensor-based technologies for precision crop management. His inventions include technologies for precision agriculture that enable farmers to plant, monitor, and harvest with greater accuracy and efficiency. The integrated systems combine artificial intelligence, vision technology, and mechanical components to help farmers make more informed decisions about crop management, He said.

Long He, associate professor of agricultural and biological engineering, works directly with farmers to develop robotic systems and sensor-based technologies for precision crop management.

His lab has developed ground-based machine-vision technology to count and monitor crop buds, flowers, and fruits on trees. The team has invented robotic systems for mechanical thinning of fruits and flower buds in orchards and has discovered a new method for precision chemical application for apple crop-load management.

"Technology can help us to provide information, help farmers to make decisions based on the data, based on the site-specific conditions," He said. "We have more unpredictable growing conditions, and that is reflected in crops."

A current research project involves using artificial intelligence to count and monitor apple buds, flowers, and fruits at different stages, and developing robotic systems that can mechanically thin or remove excess fruits using integrated vision and mechanical technologies. The goal, he explained, is to help growers make more informed decisions and address labor shortages in agriculture.

"My educational background is in mechanical engineering, so I was always interested in developing physical and mechanical systems to address problems," He said. "Agriculture is one of the most critical industries, so if we can help in addressing problems for agriculture, that is one of the most important things we can do."

By Adrienne Berard.
Photos by Michael Houtz