Kiwi Fruit seedling graft

Jason says...
Can you graft a pigs leg onto a human... Well maybe with enough drugs it'll work in the short term. But no, grafting only works within species or or rare cases outside but still closely related. Any cases where grafting works outside that range, the plants are simply wrongly catagorised.

Besides all that, there's no real purpose for grafting a seedling onto a rootstock. The usefulness of grafting is to preserve and replicate one plant. At least until it become too old genetically but most trees seem able to continue this process for a few hundred years.

Jason says...
Loquat to quince is one of the fee that go outside the genus range although there's quite some stunting with that one.

You can also use intermediate grafts to go from one genus to another sometimes, or between species that don't like it. Intermediate grafts can get you far enough along to graft all stone fruit on the one basic rootstock.