HREZ. High Resistance by Enza Zaden. | Enza Zaden


HREZ. High Resistance by Enza Zaden.

HREZ. High Resistance by Enza Zaden.

Enza Zaden introduces a growing collection of High Resistance tomato varieties against ToBRFV. This highly infectious virus remains a major threat for the tomato industry. HREZ has proven to limit the spread of ToBRFV. On this page you can read what ToBRFV is, how the HREZ varieties make a difference and how professional growers can contribute to this.

We act now

From the first news report of a new Tobamovirus, Enza Zaden has dedicated large resources in order to stop this virus from spreading. Trials with High Resistance varieties have been implemented at various locations and the results are promising. The tests at the selected locations show that Enza Zaden has high-quality tomato varieties with a high level of resistance. The plants show no symptoms under normal virus pressure. A year after the first HREZ commercial varieties were made available, we can look at a brighter future for the tomato industry.

What is ToBRFV?

ToBRFV was first detected in Israel in 2014. The crops showed symptoms of tobamovirus infection, but this particular virus had not been seen before. Research showed that it was a new virus very similar to tomato and tobacco mosaic viruses (ToMV and TMV). It became a growing concern for tomato growers and traders across the world.

In this article you can read the history of ToBRFV.

Why ToBRFV resistance is so important?

Tomato is one of the most popular vegetables worldwide. ToBRFV can lead to unmarketable tomatoes: the symptoms make the fruit unattractive. A High Resistance plant looks healthy, grows well and shows no symptoms under normal virus pressure. In addition, a Highly Resistance plant actively blocks the virus. There may be symptoms in the area where the virus first enters the plant, however the virus will not be able to multiply and spread within the plant.

That is of great importance for the tomato industry. You can read how this works in our article: what is thedifference between intermediate and high resistance?

Preventing ToBRFV from entering your tomato greenhouse.

Enza Zaden has developed High Resistance against ToBRFV in a growing collection of varieties – without compromising fruit quality and taste. HREZ is available for different types of tomato varieties, from cherry tomatoes to beef tomatoes. Even when cultivating HREZ varieties, we encourage growers to maintain good sanitary measures in their crops. Recommendations include:

  • Starting material must be certified free of ToBRFV. This applies to seeds and young (grafted) plants;
  • Water sanitation – using disinfection methods to ensure the virus is not spread by irrigation water; 
  • Limit the number of people entering the greenhouses;
  • Hands and materials such as tools, shoes and the like must be cleaned and/or disinfected;
  • Treat each greenhouse, tunnel or field as a separate unit; 
  • Minimize crop handling.

In addition, it is important to stay informed of the latest virus and resistance developments.

Stay up to date about HREZ

Data information and illustration provided by Enza Zaden on this webpage are provided to assist professional growers and users and, are based on Enza Zaden’s assessment of its test results and practical experience however without any guarantee, representation or warranty regarding accuracy thereof or purpose and/or performance of the HREZ variety in practice. Environmental conditions must be taken into account. Under no circumstances shall Enza Zaden be liable to the professional grower or user for results deviating from that information.