In Australia the plant variety rights cover commercial propagation.
I dony think that excludes individuals from owning a patented plant, if they can get it.Or does it prevent any own use propagation.
In fact there is a breeders exemption for propagating from patented vars for further research. Generally fruit vars are only released to commercial growers in large numbers, and no nursery will sell you one or two trees. Growers usually sign a licence agreement about the marketing of the fruit from the patented trees, and not re-propagating from them.
If you breed from a patented var, you could patent the results yourself,but the results cannot be genetically identical. There is a threshold of difference that must be obtained, and the plant must clearly be different to the parent in some way.
As i see it, if you obtained seed from red nules, and it turned out to be nucellar ( not always the case ) you can grow it, but if 100% identical, you couldn't commercially propagate or market the fruit.
Similarly you could go back to the original parents of any hybrid var, and perform the same cross, and possibly get something very similar.
If it is too close to the patented var. you may not be able to do much with it.
In the USA, do the plant patent laws actually prevent any individual from owning a plant??