Bayer has developed new tomato varieties that offer growers advanced solutions in the fight against Tomato Brown Rug Virus (ToBrfv). These varieties will be launched this year in all major greenhouse tomato market segments and offer multi-stacked virus resistance genes for longer-lasting protection against ToBrfv mutations.

The first generation of resistant tomato varieties has helped ensure product quality and a steady supply in recent years, but plant RNA viruses like ToBrfv mutate rapidly. This means that varieties with resistance to a single agent are more vulnerable to attack, but the accumulation of multiple resistance genes that disrupt different stages of the plant-virus interaction may offer better protection.

"ToBrfv, which breaks resistance, remains a long-term threat to farmers' incomes, so they need more durable solutions without sacrificing product quality or agronomic performance," said Javier Quintero , Global Lead Tomato R&D at Bayer's Crop Science division. "We have tested several new hybrids resistant to ToBrfv and confirmed their resistance to the resistance-breaking virus. We expect growers to achieve similar results under similar growing conditions, which is very exciting."

Bayer conducted two trials to test the resistance of four new tomato hybrids to high viral pressure. One test group was inoculated with the standard virus, the other with a resistance-breaking ToBrfv isolate. Each trial was conducted in a separate greenhouse and included a non-resistant tomato variety. At both 14 and 21 days after inoculation, the non-resistant plants showed severe ToBrfv symptoms, but those with multiple layers of resistance resisted both the standard virus and the recently characterized ToBrfv mutation.

The first tomato hybrids with multi-stacked resistance include Bayer’s De Ruiter Red Beef Ferreira tomato and Pink Beef Futumaru tomato, which are already commercially available. Bayer is launching new multi-stacked resistant hybrids for large, medium, cocktail and cherry plum tomatoes, as well as new truss tomatoes. Recent trials confirm high expectations for agronomic performance and resistance level, and the first wave of these new products will be commercially available in 2025.