Research performed by laboratory Groen Agro Control and Van Remmen UV Technology confirms the effective killing of Tomato brown rugose fruit virus (ToBRFV) in drain water by ultraviolet (UV) light. Tomato growers usually use a UV dose of 250 mJ/cm2 for the disinfection of drain water. That dose now also appears to be suitable for the inactivation of ToBRFV.
The study used drain water from tomato cultivation with a UV transmission of 10% and 20%. A high concentration of ToBRFV virus particles was added to that water by adding contaminated plant sap. With a specially available test setup (Collimated Beam), five different UV doses were applied to the contaminated drain water.
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 by means of an ELISA test. No ToBRFV was found in plants at a dose of 150 mJ/cm2 and higher. In practice, larger number of plants are used. Given the seriousness of this virus, it is desirable to use a safety margin there. That is why a UV dose of 250 mJ/cm2 is recommended to be applied, as this is the standard recommended dose, which has already been proven to be effective against other plant pathogens.
The study was carried out on behalf of “Gewascoöperatie Tomaat” from “Glastuinbouw Nederland” was made possible by four suppliers of UV-C disinfection equipment: Priva, Ridder, Infa Tech and PB-tec.
To prevent ToBRFV from spreading, reliable disinfection of the drain water will have to be combined with measures with regard to other contamination routes. The virus is mainly spread mechanically during crop handling.
For more information:
Groen Agro Control
2645 EG Delfgauw, the Netherlands