Larry Dighera wrote:
What causes low germination rates of flasked orchid seed?

Is a low seed germination rate most often due to too little pollen in
contact with the stigmatic surface at pollination time?

I would suspect that different media formulae would produce different
results for a given cross. Has anyone had any experience with this
phenomenon? Any specific media recommendations for reed-stem
Epidendrums?

How big a factor are temperature, day-length and light levels?

Are intergeneric crosses more likely to have low germination rates?

It is a ~10% germination rate of Epidendrum atacazoicum (bifalce)
selfed that prompts my question.

It's a simple question, but I suspect the answer will be complex.

Larry, while I can't direct an answer specifically to that species, I
can say the most important factor is the fertility of the parent plants.
Some plants, and some types of plants, are noted ofr low fertility;
nothing you do can increase this beyond their ability to supply viable
seed. Numerous species are self-sterile, requiring another clone to
produce offspring, and some are notoriously low producers. After all, if
the plant produces one viable seed which germinates and survives, that
is success in the wild. That said, the medium can have a major impact on
germination rates of viable seed. And the sterilization process prior to
sowing is tricky and if not handled correctly can kill off most or all
of the viable seed. I have not heard that daylength or light levels are
a significant factor for most orchids (true terrestrials and those with
a dormancy period, i.e., cyps, are exceptions). The norm for germination
of most orchid seed is low light; they really don't need very much.
Please let us know if you manage to improve your germination and what
did it.