Future of crop nutrition: Smart bacteria improve yield and quality under climate stress

Scientists are developing a new approach to food security by creating a “smart bacterium” that can reprogram crops’ responses to environmental stresses in real time. The innovation comes at a time when climate change is threatening crop health. Nutrition Insight speaks with the lead researcher to learn about the potential of this solution.

UK researchers from Northumbria University, the University of Oxford, and the University of Leeds have received nearly half a million pounds for this project. 

They anticipate that the technology will be ready for use in the field within ten to twenty years. The 18-month project, Smart Engineered Bacterial Conduits for Enhanced Crop Performance, seeks to unlock the full potential of crops while also reducing reliance on fertilizers and pesticides.

Smart bacteria are said to be able to intervene after sensing environmental cues and plant stress signals, mimicking plant hormones to support their growth.

“We’re introducing rapid, dynamic control of crop behavior in the field for the first time, reprogramming the plant in real-time to respond quickly and appropriately to stress,” says Dr. Ciarán Kelly, assistant professor of Synthetic Biology at Northumbria University.

The technology is expected to debut in areas where genetically modified agricultural bacteria are already used.

Plant survival versus yield

According to Kelly, the smart bacteria can enhance the nutritional quality of crops, not just promote growth.

Dr. Angela Sherry, Dr. Emma Riley, and Dr. Ciaran Kelly, of Northumbria University (Image credit: Barry Pells).“In its simplest form, improved growth of crops under moderate stress conditions would lead to increased biomass, leading to higher calorific content per plant and, importantly, higher protein yield in the grains of cereal crops such as wheat and corn,” he says.

Kelly points to the growth versus defense trade-off in crops, as they tend to shut down growth even at a moderate stress threshold level.

“Plants have evolved to prioritize survival over yield,” he adds.

For instance, slightly higher temperatures, slightly lower water in the soil, and slightly lower nitrate levels before fertilizers are reapplied can play a part. “This leads to a reduction of crop biomass and carbohydrate, lipid, and protein content.”

“We now want to introduce dynamic regulation of the communication between the crop and the beneficial bacteria, sensing plant stress signals through the hormones produced by the crop, and when the stress condition is not critical, e.g., water content below 5%, modify the hormone ratios to prevent the shutdown of all growth mechanisms in the plant.”

The continuous balance and control should help the plant survive while also increasing the overall yield and nutritional content of the crops, adds Kelly.

Beyond calories and key crops

Experts have said that food security needs to go beyond just calories. It must also fulfill nutritional quality in diets.

Smart bacteria are said to be able to intervene after sensing environmental cues and plant stress signals, mimicking plant hormones to support their growthRecent research found that leafy vegetables, such as kale, rocket, and spinach, under hotter temperatures and increased CO2 levels, helped crops grow faster and larger. However, the vitamins, minerals, and overall nutritional quality and content were low.

That study also warned that changing nutritional levels in crops pose a risk in diets that are higher in calories.

However, Kelly believes that the smart bacteria can enable overall nutritional quality in challenging climatic conditions by ensuring the crops produce grains, fruits, seeds, and tubers in moderate stress conditions.

He adds: “The application of our bacteria is consistent with traditional agricultural practices, either by inclusion during sowing, tilling, or spraying on leaves. Currently, we are targeting cereals, as they have such a large global market and are the staple of many diets.”

Rice, maize, and wheat — key cereal crops using the C3 pathway — supply food for billions worldwide. However, research has warned that they may be threatened by rising atmospheric CO2 levels.

Other research from the University of Adelaide, Australia, found that a symbiosis between plants and members of an ancient phylum of fungi, the fungus product, caused bread wheat plants to grow more grain and accumulate greater amounts of nutrients.

“Our choice of host bacterium is a well-characterized, robust strain used in agriculture for 40 years, forming strong symbiotic relationships with a number of host plants,” says Kelly. “This parent strain is known to help plants in some stress conditions, but not others. 

“As part of an ongoing commercialization effort, we have evolved strains that are optimized for a number of challenging soil conditions and shown stability in the rhizosphere for less than three months after addition to seeds during sowing.”

Kelly says the commercialization effort is proceeding through GainsBio, which provides microbial formulations for soil problems.

“We’re not just tweaking existing systems — we’re completely reimagining how we approach crop development. Instead of the traditional months-long process of plant genetic modification in laboratories, we’re using smart bacteria to transform the plant’s behavior in the field itself,” he concludes.