In a note it is said that letter marks on packages of seeds of tomatoes, cucumbers and other vegetable cultures designate.
Buying seeds of tomatoes, cucumbers and other cultures for crops, you see various alphabetic references on a package: F, T, R and others. These signs indicate existence of property of stability of these grades and hybrids to certain diseases.
F1 – a geterozisny hybrid
And – alternariya (a black spottiness of tomatoes)
With – kladosporiumu (a brown spottiness of tomatoes)
Tm – to a virus of a tobacco mosaic
V\to vertitsillezny withering
F – to fuzariozny withering
N – stability to defeat by a nematode
R – a phytophthora.
Figures in the bottom of a letter indicate races against which the hybrid is steady. For example, it is written R1, 2 – means, the hybrid is steady against the 1st and 2nd races fitoftoroza.
The sign F specifies that you deal with a geterozisny hybrid, instead of a grade. Badges can be a little. For example, if on a package with seeds of tomatoes Fl is written, TmVCFN, it means that it is a geterozisny hybrid, is steady against a virus of a tobacco mosaic, verticillezu, a brown spottiness of tomatoes, fuzariozu and defeat by a nematode.
(On magazine materials Real owner)