TPS

[GunnarSK]

Yesterday I sowed some of the Russian Blue (probably selfed, F2) TPS from Durgan in Ontario. I think this could have been done earlier, but just sowed them together with peppers and eggplants and before any tomatoes.
Tom's TPS from deliberate crosses are still waiting, but at least some of them will be sown now.
TPS are available commercially within the States, I don't know the company, but it is probably only Catalina potatoes, white/yellow but apparently an OP variety, which breeds true from TPS.
Christo from Bulgaria, who has his own Russian-language trading site, has TPS and also searches TPS from some other potato varieties: http://idigmygarden.com/forums/showthread.php?t=28672

[GunnarSK]

You can also save/isolate your own TPS provided you got potato berries. The seeds are tiny (much smaller than tomato seeds), but you can extract them from ripe berries (turning soft and slightly brown), using the same method as for tomato seeds (with or without fermentation). As an additional precaution you can treat them with TSP (tri-sodium-phosphate) like Tom Wagner does, as it eliminates any diseases from the TPS.