New varieties of tomatoes are set to deliver stronger, longer-lasting defence against the devastating tomato brown rugose fruit virus (ToBRFV).
New hybrids by German agrochemicals giant Bayer feature multi-stacked virus-resistant genes to guard against mutations that can overcome existing resistances.
While earlier generations of resistant tomatoes have helped maintain produce quality and supply stability, plant RNA viruses like ToBRFV mutate rapidly.
This means that varieties relying on a single resistance gene are more vulnerable to the evolving virus.
Bayer’s approach stacks multiple resistant genes that interfere with different stages of the plant-virus interaction, providing more durable protection.
Javier Quintero, of Bayer’s crop science division, said: “Resistance-breaking ToBRFV remains a long-term threat to grower incomes, so they need longer-lasting solutions without sacrificing produce quality.
“We tested several new ToBRFV-resistant hybrids, and we confirmed that they hold up against the resistance-breaking virus.
"We expect growers to see similar results under similar growing conditions, which is very exciting.”
ToBRFV poses a serious threat to UK tomato growers by causing significant crop losses and reducing fruit quality.
The virus leads to symptoms like brown, wrinkled patches on fruit, leaf mosaic patterns, and overall stunted plant growth.
This not only lowers yield but also affects the marketability of tomatoes, forcing growers to discard infected produce.
Bayer conducted two trials assessing the resistance of four new tomato hybrids under high virus pressure.
One trial group was inoculated with the standard ToBRFV, while the other was exposed to a resistance-breaking ToBRFV isolate.
Both trials included a non-resistant variety as a control. At 14 and 21 days after inoculation, non-resistant plants showed severe symptoms, whereas the hybrids with multiple resistance stacks remained healthy against both virus types.
The first hybrids featuring multi-stacked resistance include Bayer’s De Ruiter red beef Ferreira and pink beef Futumaru varieties, which are already commercially available.
In 2025, Bayer will launch new multi-stacked resistant hybrids for Large Truss, Medium Truss, Cocktail & Cherry Plum Truss, as well as new Beef tomato varieties.
Early trial results indicate promising agronomic performance alongside strong resistance, according to the firm.
