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.

I have no answers. Anyone else?

K Barrett

"Larry Dighera" wrote in message
...

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.

On Thu, 15 May 2008 07:23:01 -0700, "K Barrett"
wrote in :

I have no answers. Anyone else?

K Barrett

Thank you for your response.

Does Aaron Hicks still frequent this newsgroup?

It seems to be sort of quiet compared to what it used to be.

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.

"Larry Dighera" wrote in message
...
On Thu, 15 May 2008 07:23:01 -0700, "K Barrett"
wrote in :

I have no answers. Anyone else?

K Barrett

Thank you for your response.

Does Aaron Hicks still frequent this newsgroup?

It seems to be sort of quiet compared to what it used to be.


{laff} Heck, have you seen the OGD? Its nothing but newsfeed from some guy
in Canada. Used to be a great resource. But, that said, one only gets the
forum one participates in.

I know the old hybridizers used to wipe the stigmatic surface with orange
juice in order to increase germination rates. Something about the acid
increasing 'take'.

I know the more complex the hybrid the lower the germination rate.

I know there's a difference in yeild when crossing a complex hybrid and a
species. But I can't rememebr if you get higher yeild if the species carrys
the pod or the complex does....

As to medium, all I vaguely remember is that some genera require different
nutrients in the medium than others, but not that the medium could somehow
influence the outcome of a cross. It will be interesting to see if Aaron
picks up on this discussion. He does still look in occasionally.

Again, sorry to be of no help.

K Barrett
(OrchidSafari had a series of 3 chats on hybridizing, one of which was
published in the Orchid Digest magazine. Not all links work in the 3rd one,
but you may find something there... who knows?, even a blind squirrel gets a
nut.) http://www.orchidsafari.org/

Seems to me there are two questions the is it "low germination rate of
viable seed", or "low percentage of viable seed in the capsule"?

The former is probably medium related, while the latter would be parental in
nature.

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies. Books, Artwork, and lots of Free Info!


"K Barrett" wrote in message
. ..
"Larry Dighera" wrote in message
...
On Thu, 15 May 2008 07:23:01 -0700, "K Barrett"
wrote in :

I have no answers. Anyone else?

K Barrett

Thank you for your response.

Does Aaron Hicks still frequent this newsgroup?

It seems to be sort of quiet compared to what it used to be.


{laff} Heck, have you seen the OGD? Its nothing but newsfeed from some
guy in Canada. Used to be a great resource. But, that said, one only gets
the forum one participates in.

I know the old hybridizers used to wipe the stigmatic surface with orange
juice in order to increase germination rates. Something about the acid
increasing 'take'.

I know the more complex the hybrid the lower the germination rate.

I know there's a difference in yeild when crossing a complex hybrid and a
species. But I can't rememebr if you get higher yeild if the species
carrys the pod or the complex does....

As to medium, all I vaguely remember is that some genera require different
nutrients in the medium than others, but not that the medium could somehow
influence the outcome of a cross. It will be interesting to see if Aaron
picks up on this discussion. He does still look in occasionally.

Again, sorry to be of no help.

K Barrett
(OrchidSafari had a series of 3 chats on hybridizing, one of which was
published in the Orchid Digest magazine. Not all links work in the 3rd
one, but you may find something there... who knows?, even a blind squirrel
gets a nut.) http://www.orchidsafari.org/

Larry,
I'm still a 'student' of hybridizing but a few things come to mind.
This may be elementary info for ya'll.
If you repeat that cross, try soaking the pollinia in *enzymatic*
contact lens cleaner for about 5 minutes. No need to rinse. The
solution removes the protein covering making the pollen more
available.
Use a bloom for the parent side that has opened between 24 and 48
hours.
Leave the pollen intact on the receiving bloom. The bloom stays
receptive longer.
I cannot share a formula for Epi media but of course that could be the
problem.
Use 'people' temps 65-75F to maintain the flasks. (Although some use
higher fluctuations).
In the primary/mother flask I put them in low light on an eight hour
timer.

Thanks for asking the question. I hope many with experience do
contribute.
I'll be reading... and learning,
Lee (in HHI, SC)


On May 14, 5:22*pm, 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.

That's interesting, Lee.

I was told that mashing the pollinia on a piece of waxed paper also helped.

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies. Books, Artwork, and lots of Free Info!


"Savor" wrote in message
...
Larry,
I'm still a 'student' of hybridizing but a few things come to mind.
This may be elementary info for ya'll.
If you repeat that cross, try soaking the pollinia in *enzymatic*
contact lens cleaner for about 5 minutes. No need to rinse. The
solution removes the protein covering making the pollen more
available.
Use a bloom for the parent side that has opened between 24 and 48
hours.
Leave the pollen intact on the receiving bloom. The bloom stays
receptive longer.
I cannot share a formula for Epi media but of course that could be the
problem.
Use 'people' temps 65-75F to maintain the flasks. (Although some use
higher fluctuations).
In the primary/mother flask I put them in low light on an eight hour
timer.

Thanks for asking the question. I hope many with experience do
contribute.
I'll be reading... and learning,
Lee (in HHI, SC)


On May 14, 5:22 pm, 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.

Howdy, y'all. Yes, I'm still around. I'd venture to say I'm
probably one of the few- if not the only- to read every single message
that has gone through this newsgroup since '94. I don't post much since
the questions are usually handled very well. Plus, I haven't figured out
how to quote messages using pico in this shell account, and I'm not about
to learn some newsreader. How's that for stubborn old cootness?

Anyway- the first question as to why there's such low germination
would depend upon viability. Is the plant producing good seed to begin
with? Light microscopy at 100x or even a little less is enough to see if
the seeds have embryos. If the embryo count is low, all other bets are
off- the seeds aren't viable to begin with if there's no embryo.

In order to get good embryos, the cross needs to be good. There
are intrinsic issues with compatibility- usually genetic, sometimes
mechanical. Getting the right pollen into the right plant is essential;
for hybridizing, the pollinia from the larger flower goes into the smaller
one. Imagine how Soph. coccinea pollinia would have to grow pollen tubes
all the way down the column in an 8" cattleya. Ain't gonna happen. Once
the pollinia are selected, some hybridizers treat the pollen; as
mentioned, enzymatic lens cleaning solution works for some. Others report
whetting the pollinia with their saliva- which is heavy in enzymes that
do... who knows what. Others dip it in "7-Up," or other soda (I think one
grower recommended Sunkist to me).

Why these treatments work is unknown; perhaps the low pH of sodas
work, along with some sort of "skin" effect. If the stigmatic surface is
dry, that's too bad for the pollen grains. Once soda dries, it leaves a
sticky coating behind; maybe soda helps seal in the fluids on the
stigmatic surface? Your guess is as good as mine. Good physical contact is
a must; mashing the pollinia into the stigmatic surface (which should be
fresh- for flowers that last more than a few days, they should be
pollinated within the first week- and immediately if they last only a day
or so) helps foster the formation and growth of pollen tubes, which is
very important to the fertilization of the ovary. Get that toothpick in
there, and render the pollinia into the stigmatic surface.

And then it's X months of waiting, until the capsules split.
Again, check seeds for embryo counts. Mature, healthy seed will have fat
embryos, while barren seed will look like dehydrated husks. Dry seed
carefully for a day or so, either in air or in a desiccator with some
calcium chloride. Package and store on clean, dry paper.

Sowing isn't such a big deal for common genera such as
epidendrums. However, as disinfection is the step that makes everyone
(myself included) whine like a bad serpentine belt on a December morning,
I find it best to sow on at least two types of media. Disinfection hard,
sowing easy: may as well make the best of the issues at hand, right?

So, I disinfect the seeds; 8% bleach solution (which is now 6%
sodium hypochlorite, versus the old 5.25%, so less needs to be used) is
fine. I use fancier stuff for really nasty seeds; not everyone is so good
about drying and treating their seeds right after harvesting, but clean,
dry seed is readily disinfected in this manner. Wash once, and sow on
media. I use P669 (which is PhytoTech Labs P668 with 5 grams of B852
banana powder added), and one or more other media. My second favorite is
Western Labs W2.5 with coconut liquid. My third favorite is N1, which I
originally developed for Nepenthes, but it works well for some weird-o
orchids. From there, you get into really exotic formulations. If it's not
some weird cypripedium, it'll germinate on one of those three media if
it'll germinate at all.

I think that answered all the important questions. If not, I'll be
back in a couple of days or so.

The address in the header isn't valid. Send no email there.

-AJHicks
Chandler, AZ