The Tomato Brown Rugose Fruit Virus (ToBRFV) is keeping greenhouse horticulture under its spell. ToBRFV is a highly contagious virus that can be found on tomatoes, peppers and chili peppers and can cause a lot of economic damage to greenhouse companies. Besides tightening up the hygiene measures at the company, there is also increasing knowledge of new preventive measures against ToBRFV. One of the new insights is control by means of UV treatment of the drain water.

Recent research by the Dutch laboratory Groen Agro Control and Van Remmen UV Technology confirms the effective killing of the Tomato Brown Rugose Fruit Virus (ToBRFV) in drain water by ultraviolet (UV) radiation. Tomato growers usually use a UV dose of 250 mJ/cm2 for disinfecting drain water. This dose is now also suitable for the control of ToBRFV.

Research results
The research used drain water from tomato cultivation at a UV transmission of 10% and 20%. A high concentration of ToBRF virus particles was added to this water by adding contaminated plant sap. With a special test setup (Collimated Beam), five different UV doses were administered to the contaminated drain water.

Safety margin
At each UV dose, 10 tomato plants were inoculated with the treated drain water and the plants were examined for the presence of ToBRFV after two weeks via an ELISA test. At a dose of 150 mJ/cm2 and above, no ToBRFV was found in the plantlets.

In practice, larger numbers of plants are used. In view of the seriousness of this virus it is desirable to use a safety margin. Therefore, it is recommended to apply 250 mJ/cm2 for ToBRFV as well, since this standard recommended dose has proven to be effective for other plant pathogens.

Other infection routes
To prevent ToBRFV from spreading, reliable disinfection of the drain water will have to be combined with measures with regard to other infection routes, the researchers emphasize. The virus is mainly spread mechanically during crop operations.

Disinfecting drain water with UV systems
Ridder offers with the VitaLite water treatment system a suitable solution to disinfect drain water with UV treatment. This system is used worldwide by growers who want to recycle their irrigation water and fertilizers as much as possible. The UV treatment breaks down pathogens and bacteria in the drain water so that it can be safely reused.

Want to know how UV treatment of drain water can help fight ToBRFV? Then contact us or request a 1 on 1 meeting with one of our water specialists.