Our discovery of the ToBRFV genome – the foundation for today’s resistant varieties

By Marco Mammella

The Tomato Brown Rugose Fruit Virus (ToBRFV) is slowly losing its grip on tomato growers worldwide as seed companies are launching more and more resistant tomato varieties. BASF | Nunhems alone has over 25 in its portfolio and will add more varieties in the next years.

It seems that the fight against this existence-threatening pathogen can be won – and I am proud to have contributed a big part to this by working on the identification of the virus and sequencing of the entire ToBRFV genome back in 2015.

When the virus appeared, we sequenced the gene of the coat protein (cp) and the results suggested that we were dealing with a common virus of the Tobamo family, a different strain of tomato mosaic virus (ToMV) which would not be a big issue since strain variations with lower fitness popped up already and disappear again by itself. But our research team at BASF | Nunhems sensed that something was different, and we decided to sequence the full genome of the virus – as the first company ever.

This decisive step revealed the devastating nature. We understood that it was a new species of the Tobamovirus type and for that would easily be a new threat since these are viruses transmitted mechanically and seedborne. It was the foundation for our decision to invest in the development of resistant varieties immediately. The quest moved to the top of our agenda and in 2020, we were among the first to introduce the first resistant seeds when growers around the globe were already seeing their harvest destroyed by the virus.

Of course, our work did not stop when the genome knowledge was complete. We are constantly working on innovations to improve the resistance and combine it with other desired traits. Now we are taking our breeding to the next level by combining different mechanisms that block the virus and new strain variations at different levels. The outcome will be even more resistant tomato plants and bear fruit with all the characteristics that growers and consumers require.