The PROBITY project has brought novel wheat lines out of the lab and into farmers’ fields under rigorous scrutiny from scientists, growers and food processors. On-farm trials have started this autumn with three varieties being drilled by BOFIN’s PROBITY Pioneer farmers.
Agriculture is under pressure, and traditional plant breeding simply can’t keep up. Precision breeding including gene editing could change that, bringing more resilient and productive crops that require fewer inputs to market much more quickly.
In 2023, the UK passed the Genetic Technologies (Precision Breeding) Act, paving the way for approved gene-edited crops to be produced and enter the food chain from November 2025 onwards when new regulations come into force. As England is currently the only location in Europe where such precision-bred varieties can legally be trialled in farmers’ fields the PROBITY project will aim to exploit this unique opportunity.
But regulation alone is not enough, says BOFIN founder and PROBITY project lead Tom Allen-Stevens. “To convince farmers, breeders, processors, and consumers, these traits must be proven on metrics that matter such as grain yield, disease resilience, root performance, and processing quality. PROBITY is designed to bridge that gap.”
This year (2025-26) the project’s on-farm trials focus on two traits which have been introduced to wheat via TILLING:
- Low asparagine – developed at Rothamsted Research this trait introduced to Claire wheat is believed to reduce acrylamide formation in wheat products when baked or toasted – a key issue for breakfast cereals, snacks and biscuits.
- Steeper rooting – developed at the John Innes Centre this trait introduced to Cadenza wheat could increase drought tolerance.
The PROBITY Pioneer farmer trialists will grow these alongside control plots to compare yield, rooting depth, plant vigour and grain quality.
What Is TILLING?
TILLING stands for Targeting Induced Local Lesions in Genomes. The process involves soaking seed in a chemical which causes changes in the DNA, however the changes are unpredictable and randomly scattered across the genome.
“We typically see about 5,000 variations per seed and most of those won’t make any difference to how the plant performs, however around 15 percent will alter gene function and have potential impacts on plant traits,” explains John Innes Centre scientist James Simmonds who developed the Steeper Rooting lines. Researchers then cross the altered seed back to its original variety (in this case, Cadenza), which removes unwanted variations. “After several rounds of backcrossing we extract two sister lines, one carrying the desired genetic variation in the genes of interest and one without, which we then advance for comparison in field trials,.”
With the two John Innes PROBITY varieties the genes selected are EGT1 and EGT2. This stands for Enhanced Gravitropism which controls how the plant’s roots respond to gravity.
“With these genes switched off, the roots respond more strongly to gravity and grow steeper,” explains James. “We are interested to know how the altered root architecture impacts yields and whether it can improve drought tolerance.”
Six PROBITY Pioneers will be trialling the EGT1 and EGT2 varieties and one further Pioneer is putting the low asparagine line through its paces.
This line was developed at Rothamsted Research, also by TILLING. This year’s trial will enable some large-scale processing and testing of the resulting grain to see how the trait performs under real-world conditions and whether it does indeed deliver lower levels of acrylamide. There is a precision-bred line too which – pending approval – will enter trials next year.
The PROBITY Pioneer’s role
The farmer trialists have been tasked with establishing replicated trial plots of the PROBITY lines (Claire and Cadenza variants) alongside control lines. Throughout the season they will measure agronomic performance including scoring the crops for signs of disease. They will collect data via the new BOFIN Trialist app which includes an additional AI tool that calculates plant count from photographs. The Pioneers are being encouraged to take frequent images to help train and refine the model.
They will also be sampling both roots and soils, including taking soil cores for CT analysis to verify differences in root architecture. Finally, they will collect grain for processing and assessment.
As the necessary regulation comes fully into force from November 2025, the project’s outputs can move forward more easily and feed into broader discussions, explains Tom Allen-Stevens.
“The trials are playing an important role in not just weighing up the potential benefits of precision-bred varieties under realistic farming conditions, but also in assessing whether farmers will trust and adopt these lines. It is also enabling us to see the response from processors and others in the supply chain,” he adds.
“If successful, PROBITY will act as a platform rather than a one-off trial – a demonstration model to accelerate precision breeding pipelines across cereals and beyond. The proof will lie in the data that emerges – whether the precision-bred lines can hold their own or improve performance – on real farms, and whether farmers, processors and consumers will want to adopt them.”
Found in:
Issue #3
Celebrating 5 years of farmer-led innovation
From guesswork to ground truth: mapping the future of pest control
SLIMERS Project advances in the battle against slugs
‘Slug trials’ test nematode application techniques
Wholecrop beans are a win-win for livestock performance and sustainability
Gaining ground with novel wheat lines
Landrace wheats on trial
Rooted in Research
It’s easy to ADOPT, harder to commit