Ah yes, Black prince, черный принц one of the more common cultivars in Russia and Ukraine. In "mulberry ( MORUS L.): ITS REALITY AND FUTURE IN UKRAINE "-text that I found probably in researchgate it is told that it is one of the “anonymous found local forms” , so not produced in any sericulture program. I have four ones that go into ground this fall, now they just wait in pots. It can be bought from EU, at least one man in Lithuania sells me them, and he is quite reliable, I’ve visited his “200 mulberry trees in a field”-operation in Kaunas.
Black prince is only one large berried, and not even the most famous one in eastern block. For my part, I am in southern Finland trialling mulberries as I get them and I read in one Russian forum that it can take Moscow winters without large damage.
Most famous and “hyped” ones are Shelli no.150 and Galicija-1 (or just Galicija), the latter was produced in the Merefensky Institute of Sericulture, author Galina I.Babaeva.
It is the most productive and large berried of the Morus albas that I’ve ever seen. Well it is a " omplex interspecies hybridization and followed by multiple individual selection among the hybrid plantations of Italian descent.", whatever that means. Those I can buy from Lithuania by the bucketloads since they are micropropagated, and it seems some Polish nurseries already sell that, so get your own! Though it is one of the less hardy of the Ukrainian ones, still the vigor outperforms the winters damage easily.
Shelli no.150 is the most overall best performer apparently, good producing, big berry, transports better and taste is best of all. Leonid Prokazin, a mulberry enthousiast that has trialled over 150 cultivars in Ukraine, bought the small plants some 20 years ago from Poltavan priest, and since the plant was so succesfull, began to spread it around.
I’ll include pictures of both Galicija and Shelli (NOT Shelley, mind you) and If I can I’ll add also one or two badly translated texts of Prokazin and others. And I can’t read even Russian, so all this is done by translating…the hours I spend on obscure Russian and Ukrainian forums and sites 
EDIT: The first two pics are Shelli, then Galicija and last pic there is three cultivars, the rightmost ones are Shelli.
(68) Mulberries Prokazin Leonid Ilyich.doc (326 KB)
