On Dec 10, 3:22*am, "K Barrett" wrote:
There was an article in Orchid Australia saying the blue color came from two
chemicals (a flavoniod and another one) and they had to both be present in
the parental stock in order to pass the blue trait on. *And not all parents
had both even though they came from the same cross. *I admit I don't really
understand the article so I may be misstating it.

While there may be other anthrocyanins (the main flavanoids that
produce red-blue pigments) present in orchids, from what references I
can find, cyanidin seems to be the major anthocyanin that produces
blues in orchids (eg blue Thelymitra, Vanda coerulea etc). I read
through both the Morris article and the Banks and Woolf article that
Morris cites. While the Banks and Woolf idea of blue transmisson does
seem a bit too alchemical, I suspect Morris's thoughts of just needing
the right amount of anthocyanin and co-pigment contributed by
different parents is a bit too simplistic. In the case of a hybrid
like Susan (falcatus x wenthalii) there is little doubt that both
parents contain anthocyanin (how else does falcatus get the red
striping on the labellum) and, given that most other Sarcs contain
anthocyanin, what is it about weinthalii that makes the wenthalii/
falcatus anthocyanin:co-pigment ratio perfect for producing blue tones
that are unable to be replicated in any other falcatus hybrid?
Furthermore, how does the blue carry through to James Woolf when the
addition of harmannii should theoretically add a lot more anthrocyanin
into the mix? No doubt anthocyanins and co-pigments need to be present
to produce blue flowers but I suspect the process is a lot more
complex (ie, the cell conditions needing to favour the necessary ionic
state of the anthocyanin, patterning genes expressing anthocyanin and
co-pigment pathway genes in the right tissue, etc).

Anyhow, interesting that yellow is the flavor of the month. *Looking at
Woolf's page he also has greens & oranges. *Yellow is by far the more
intense coloration. *Looks like Woolf et al have been working on creating
these lines since the mid 90s. *Now there's a guy who can stay focused on a
task, *G*

The colour spectrum of Sarcochilus has expanded dramatically in a
relatively short space of time. Certainly they've done well with
breeding reds. These days you can buy red breeding line seedlings
from quality breeders with good odds that the flower will actually be
red. One of the problems with Sarc breeding is that it's difficult to
get away from using hartmannii or fitzgeraldii in the hybrids. For all
the talk of using falcatus to bring out and spread colours in the
Morris and Banks & Woolf articles, falcatus is still not a
particularly easy plant to maintain long term. Hybrids between it and
the other epiphytic species are not particularly easy to grow (there's
not a lot of hybrid vigour when neither parent is vigorous) so you
still have to rely on hartmannii and fitzgeraldii not to mask, dilute
or centralise the colour.