- World Vegetable Center has developed tomato varieties that combine resistance to whiteflies and viruses with commercial fruit quality.
- These advances mean tomatoes can be produced with less reliance on chemical pesticides, potentially improving profitability and sustainability for farmers while reducing health risks for growers and consumers.
- The new tomato lines were achieved by isolating natural resistance traits from wild relatives.
After a decade of research, WorldVeg says it has developed tomato lines that are resistant to whiteflies and the viruses.
For years, insect-resistant tomato plants were known to bear fruit that was small, misshapen and unsuitable for commercial markets.
These resistance traits were inherited from wild tomato relatives, which also yielded poor fruit quality.
This forced growers and seed companies to choose between resilience in the field and market appeal.
After ten years, the programme produced tomato lines and hybrids that tolerate whiteflies and the viruses they transmit.
WorldVeg believed that this would open the doors to new commercial varieties that can be grown with reduced reliance on chemical pesticides.
“For a long time, seed companies and tomato farmers were faced with a trade-off – resilience or market quality. Now we have both in the same tomato, and that’s a huge breakthrough for everyone involved,” said Assaf Eybshitz who headed the WorldVeg tomato breeding program from 2022.
“From breeders to farmers and across the entire value chain, it opens the door to more stable production, reduced losses, and improved profitability under increasingly challenging growing conditions, while also reducing reliance on chemical inputs and offering potential health benefits for both farmers and consumers.”
WorldVeg said it was accelerating the path to market through the APSA-WorldVeg Vegetable Breeding Consortium, a public–private partnership that brings together seed companies and crop breeders.
Under a special project within the consortium, seed companies will be able to access seeds of the dual-resistant tomatoes, run trials in target locations and work with their own breeding teams to further improve yield and fruit quality.
The overarching goal was to develop competitive commercial hybrids and accelerate delivery to farmers worldwide.
Breeding work
The work started with the discovery of the natural resistance of a wild tomato relative, Solanum galapagense.
Some of these tomatoes were protected by a dense layer of tiny leaf hairs, known as glandular trichomes, which secrete sticky compounds called acylsugars.
These traits made the plant hostile to whiteflies, limiting the insects’ ability to feed, settle and reproduce.
The scientists isolated the trait into elite tomato breeding lines that met market standards using marker-assisted selection, a breeding technique that relies on DNA markers to identify and track desirable traits as plants are crossed over successive generations.
By repeatedly crossing these lines with large-fruited tomatoes and developing hybrids, WorldVeg breeders were able to retain resistance while steadily improving fruit size and appearance.
At the same time, it was developing tomato lines with resistance to tomato yellow leaf curl viruses, one of the most damaging diseases transmitted by whiteflies.
The key breakthrough was combining both insect resistance and virus resistance in the same tomato line.
“WorldVeg breeders knew early on that tackling the virus alone wasn’t enough – you also have to stop the insects that spread it. That meant taking a much longer, more complex breeding approach, but one with a potentially far greater payoff,” said Eybshitz.
Alongside breeding, the team carried out large-scale field trials to test how the tomatoes performed under real farming conditions.
The plants were evaluated across different seasons, climates and production systems to ensure resistance remained stable and fruit quality consistent outside controlled environments.
