In article , "Peter Jason"
wrote:

Thank you for the replies. I am searching the US patent office plant
database for new species but most are "cultivars" which are produced by
grafting. In short I am looking for a case where grafting procedures
produce new species without viral interaction. I take it, then, that if a
cultivar can be cross bred with anything, and then produce Mendalian
breeding charateristics, we have a brand-new species?

Hybrid cultivars are not new species. Even intra-species hybrids (select
strain or subspecies bred together) can end up looking vastly different
from the natural wild parents. If a sport occurs in your garden of
something common, or two plants from different continents hybridize in
yoru garden seeding strange intermediate types (as happens with
crane's-bills quite often), these novel mutations can be preserved &
developed as new strains, & might eventually be registerable as official
cultivars, but they won't be new species.

Many rhodies, tulips, & other long-gardened plants have been crossbred &
re-crossbred so many times that it is not possible to assign them any
Latin botanical name at all, but by no means makes them new kinds of
botanicals. A great many would not even survive outside of gardening
situations as they cannot produce seeds; they persist only from cloning,
division, or from stem & leaf cuttings, & can be produced by the thousands
with human assistance, but would be lucky to persist even as individual
clumps if planted in the woods & forgotten.

If however a hybrid were completely fertile, escaped to the wild, &
naturalized for decades or centuries, it could conceivably become
recognized as a new species. Tulipa marjoletti is believed to have once
been a gardened tulip of unknown ancestry, a variety that died out of
cultivation, but naturalized in the Savoy alps, was rediscovered, given a
species name, & subsequently again gardened as a "botanical" or species
tulip. Some taxonomists call these sorts of species tulips "Neo-Tulipae"
because they have not existed a particularly long time, yet they are
nevertheless regarded as their own species now, & this could happen with
other cultivated plants in the future.

Taxonomic arguments happen all the time, about intermediary types of
plants which are naturally occurring crosses between closely related
species with overlapping ranges, & whether or not these should these
should be given species status. Very widespread species often have
regional populations totally different looking from regional populations
elsewhere, but being a different size or color or curious leaf-form is not
sufficient to qualify it even as a variant. By contrast, two plants that
look identical, but have different numbers of stigma or some
distinguishing factor visible only with a microscope, would be completely
different species. Now that DNA tests have been added to the taxonomic
questions, many plants formerly thought to be of differing species are now
lumped together as all the same species, as with the common hepatica which
used to have several species now relagated to at most subspecies. Several
types of ferns once thought to be regional variants are now known to be
natural hybrids, but not given distinct names unless as selected varieties
in cultivation, then they score commercial names that might or might not
end up as registered cultivar names.

-paghat the ratgirl

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
See the Garden of Paghat the Ratgirl: http://www.paghat.com/