Inhorticulture, a graft-chimaera may arise in grafting at the point of contact between rootstock and scion and will have properties intermediate between those of its "parents". A graft-chimaera is not a true hybrid but a mixture of cells, each with the genotype of one of its "parents": it is a chimaera. Hence, the once widely used term "graft-hybrid" is not descriptive; it is now frowned upon.
Propagation is by cloning only. In practice graft-chimaeras are not noted for their stability and may easily revert to one of the "parents".
Article 21 of the ICNCP stipulates that a graft-chimaera can be indicated either by
A graft-chimaera cannot have a species name, because it is simultaneously two species. Although + Laburnocytisus 'Adamii', for example, is sometimes seen written as if it were a species (+ Laburnocytisus adamii), this is incorrect.[citation needed]
Charles Darwin "The Variation of Animals and Plants Under Domestication" Archived 2009-02-05 at the Wayback Machine, 1868 г.:
I will therefore give all the facts which I have been able to collect on the formation of hybrids between distinct species or varieties, without the intervention of the sexual organs. For if, as I am now convinced, this is possible, it is a most important fact, which will sooner or later change the views held by physiologists with respect to sexual reproduction. A sufficient body of facts will afterwards be adduced, showing that the segregation or separation of the characters of the two parent-forms by bud-variation, as in the case of Cytisus adami, is not an unusual though a striking phenomenon. We shall further see that a whole bud may thus revert, or only half, or some smaller segment.
The following graft-chimaera genera are accepted:[2]
