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Innovative Spraying Technology Promises Sustainable Agriculture Solutions

Farmers face the challenge of balancing effective agricultural practices with environmental stewardship. A recent breakthrough developed by a research team at MIT and its spinoff company aims to address this dual challenge by minimizing the use of agricultural sprays, including fertilizers, pesticides, and herbicides. This reduction is expected to decrease environmental runoff, cut costs for farmers, and potentially increase their productivity—a scenario that supports the notion of a win-win-win approach.

The core of this innovation involves a new system designed to optimize the application of chemicals during spraying. By applying a thin coating around droplets as they are released onto crops, this technology enhances droplet adherence to plant leaves, significantly reducing waste due to bounce-back to the soil.

The findings are detailed in a paper published in the journal Soft Matter, authored by recent MIT alumni Vishnu Jayaprakash PhD ’22 and Sreedath Panat PhD ’23, along with graduate student Simon Rufer and Professor Kripa Varanasi from MIT’s mechanical engineering department.

Research highlights the critical role of pesticides in maintaining agricultural yield. It suggests that without them, farmers risk losing 78 percent of fruit, 54 percent of vegetables, and 32 percent of cereals. However, despite their significance, many farmers lack the technology to monitor and refine their spraying methods. Consequently, they often default to personal experience, resulting in excessive application and subsequent runoff into waterways.

Excessive pesticide use is a pressing global issue, with one study indicating that 31 percent of the world’s agricultural soils are at high risk due to pesticide contamination. Furthermore, the financial burden on farmers is substantial, as demonstrated by the $16 billion spent annually in the U.S. on pesticides alone.

Enhancing spray efficiency is key to achieving both economic and ecological sustainability in food production. The spraying process primarily involves mixing chemicals with water and applying droplets to plant leaves that typically exhibit water-repellent characteristics. “Over more than a decade of research in my lab at MIT, we have developed fundamental understandings of spraying and the interaction between droplets and plants,” Varanasi explains.

Initially, the research team explored a dual-nozzle spraying system, which employed oppositely charged mixtures to increase droplet retention. However, they found that the complexity of adapting existing farm equipment discouraged widespread adoption. Therefore, they shifted focus to a more straightforward solution.

Through their research, the team found that using a single-nozzle system could deliver similar droplet retention improvements. Instead of electrically charging the droplets, they applied a very thin oily coating around each droplet, enhancing its ability to adhere to surfaces.

Laboratory experiments conducted with high-speed cameras unveiled that uncoated droplets on a hydrophobic surface would typically flatten and then bounce away. In contrast, when droplets were treated with a minuscule layer of oil—constituting less than one percent of the droplet’s liquid—the droplets not only spread out but remained adhered to the surface, showing a hundredfold increase in their retention capability.

Rufer explains, “When these droplets hit the surface and expand, they form an oil ring that effectively pins the droplet to the surface.” The team subjected the droplets to various experimental conditions to understand the mechanics of droplet behavior more thoroughly, consistently noting a significant reduction in rebound height irrespective of droplet size or impact velocity.

The researchers initially utilized soybean oil for their coatings, reasoning that it would be readily available for farmers. It became evident, however, that many farmers did not have direct access to this oil in their usual supply chains. Subsequent tests revealed that commonly used surfactants and adjuvants in agriculture could yield similar benefits, allowing farmers to utilize familiar materials for enhanced spraying efficacy without introducing new chemicals.

AgZen, co-founded by Varanasi and Jayaprakash, aims to commercialize this innovative system. To validate their technology’s effectiveness in improving spray retention, they developed a monitoring system named RealCoverage. Deployed on farms ranging from small holdings to vast operations, this system has reportedly saved farmers between 30 to 50 percent on their pesticide costs by optimizing current spraying practices. In 2025, this technology is set for further rollout across 920,000 acres, spanning several states in the U.S. and countries including France and Italy.

Jayaprakash, the lead author of the research and CEO of AgZen, estimates that optimizing pesticide use could result in significant financial savings for U.S. farmers. “You could give back a billion dollars to U.S. growers if you just saved 6 percent of their pesticide budget,” he asserts. In laboratory settings, enhancements led to more product effectively remaining on plants: “In the lab we got 300 percent of extra product on the plant,” he notes.

The new system has effectively streamlined existing practices; instead of drastically altering their methods, farmers can simply switch their nozzles to achieve better results with the same materials they already use. Jayaprakash adds that this approach has improved the uptake of products on various crops, including kale and soybeans, without increasing the potential for plant damage.

This technology isn’t limited to pesticides alone. “The really cool thing is this is useful for every chemistry that’s going on the leaf, be it an insecticide, a herbicide, a fungicide, or foliar nutrition,” Varanasi emphasizes, with plans to deploy the new spray system across approximately 30,000 acres of farmland this year.

Considering the projected growth in global population, Varanasi emphasizes the urgency of improving food production efficiency. “The amount of food production has got to double, and we are limited in many resources; for example, we cannot double the arable land. This means that every acre we currently farm must become more efficient and able to do more with less,” he explains. The advancements in spraying technologies, encompassing both monitoring systems and droplet coating, are poised to transform agricultural practices significantly.

AgZen has recently secured $10 million in venture funding to expedite the deployment of these innovative technologies aimed at improving chemical input management in agriculture. Varanasi concludes, “Our mission is to use these technologies to deliver improved outcomes and reduced costs for the ag industry.” The ongoing research and practical applications illustrate a future where agriculture can be both profitable and environmentally sustainable.

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