In the wild, orchid
species rarely form natural hybrids in zones of overlap. The integrity
of species is maintained by differences in flowering times, floral
morphology, visual and olfactory cues, as well as by genetic
incompatibility or inability of the hybrid to establish and reproduce.
Once one or more of these barriers or isolating mechanisms are removed,
though, for example when orchids are pollinated by hand in the
greenhouse, two different species will often produce viable hybrids
quite readily. Artificial hybrids are common between species in the
same genus, between species of different genera in the same sub tribe,
more rarely between species in different sub tribes (but within the
same tribe). In fact, the genes from as many as six different genera
are present in some hybrids, leading to the perception of orchids as
most promiscuous plants indeed!
For example, Cattleya
mossiae x Laelia purpurata became Laeliocattleya (abbreviated as
Lc.) Canhamiana. When a Laeliocattleya was then crossed
with a species (or hybrid) of Brassavola the hybrid genus name became
Brassolaeliocattleya (abbreviated as Blc.). It was not long before the
genes of yet a fourth genus were added, and the former method of simply
combining generic names had become unwieldy. Accordingly, the practice
of creating generic names ending in -ara was adopted for hybrids with
genes from multiple genera.
|