The extremely stable RNA virus Tobacco mosaic virus (TMV) was selected as the test virus. It withstands high temperatures (thermal inactivation point TIP) and has a long life resistance outside the host cells (resistance in vitro, BIV) and is therefore comparably stable like the Tomato brown rugose fruit virus (ToBRFV), which has appeared in tomatoes for some time also known colloquially as the Jordan virus.
However, since TMV is endemic in this country and is not on the alert list of the EPPO (European Plant Protection Organization) it was selected as a test virus to avoid possible contamination during experiments with ToBRFV to exclude.
TMV-infected leaf material from tobacco Nicotiana was used as a positive control tabacum cv. Samsun nn homogenized in a porcelain mortar and with 0.1 M Potassium phosphate buffer pH 7.0 made up to 120 ml.
The hypersensitive plants were used as test plants Tobamo virus responsive Nicotiana tabacum cv. Xanthi nc selected.
These are very responsive sensitive to an infection and show with the formation of necrotic spots (local lesions LL) with it, whether the applied Tobamo virus is infectious or (in the absence of LL) becomes inactivated.
In this experiment, the inactivation of the virus with the test agent Ökopur med forte (Active substance 1800 ppm Na hypochlorite) after adding the highly infectious inoculum tested at different exposure time intervals.
The inoculum was used as a positive control Potassium phosphate buffer diluted to the same concentration as before the mixture with the Test substance. (20 ml inoculum + 60 ml test substance or buffer).
The time intervals after adding the inoculum were 1-10 min., 30-40 min. And 60-70 min.
For the 60 ml disinfectant solution, 20 ml inoculum were placed in a tightly sealable plastic bottle given by shaking well mixed and started after 1 min., the mixture on hypersensitive responsive Nicotiana tabacum cv. Apply Xanthi nc with a universal brush.
The 3 lowest mature leaves of the plants were previously evenly dusted with carborundum powder been. The Ökopur® med forte + inoculum mixture was started and 4 Plants (i.e. 12 leaves) inoculated.
Since inoculating takes some time, a Stopwatch kept running during inoculation. This process takes about 10 minutes per 4 Plants. Hence the time intervals.
After inoculating the test substance, the inoculated Test plants sprayed with tap water and placed on a greenhouse table with lighting and automatic irrigation set up.
The positive control (buffer + Inoculum) do the same. This test procedure was carried out a total of three times in the specified time intervals repeated. A total of 24 plants were treated in this way.
After 3 days, the formation of local lesions was evaluated.
Result: The test substance (Ökopur® med forte) had already after the shortest time interval (1st Min.) Completely inactivates the virus. On the test plants with positive control there was a strong to observe complete necrotization of the inoculated leaves, so that the number of formed Lesions could not be counted.
Conclusion: Ökopur® med forte has a complete effect after only a short period of exposure (1 min.) inactivating effect on the very stable test virus tobacco mosaic virus (in liquid).
Another attempt is to test the effectiveness of Ökopur® med and Ökopur® med forte after another Dilution must be checked for equal low concentrations.