PHOTOs: Before and After Pollination

[LJA]

For those of you who haven't seen this, there are some fascinating changes that take place in many flowers of the Oncidiinae tribe after they've been pollinated, and I thought it would be interesting to show one of those. Most folks who have pollinated these guys have noticed that, after a successful pollination, the flower color changes and the bloom begins to almost imediately fade. But here's something a little more subtle that many people may not have noticed, and if you've never pollinated these, this mechanism is just downright cool beans!

These are pics of Mtdm. Cleo's Pride, and I wanted to direct your attention to two structures on either side of the stigma that look like flaps, or wings. I'm sure these have a scientific name but I can't find it right now, so I just called them "Stigmatic Wings."

In these first two pics of the flower before pollination, these wings are spread widely apart, exposing the flower's concave stigmatic surface between them. The stigmatic cavity is filled with a sticky, viscous fluid that serves to keep the pollinia trapped inside the stigma, and the fluid also helps initiate a burst of incredibly rapid cell growth of a structure called a pollen tube. This tube grows from the pollen all the way through the center of the flower until it reaches the flower's ovary, back behind the petals and sepals. Here's a front view of the stigma and those stigmatic "wings:"



And a side view, so you can make them out a little better:



Now here's the very cool part!

Literally hours afer being pollinated (and remember this is an orchid, so what's going on here is happening at an astonishing rate), the Stigmatic Wings begin to close over the stigma, until the entire stigmatic cavity has been covered and blocked off! These structures serve as gates, both protecting the pollen already inside from being disturbed, and ensuring that no further pollen can enter.

Here's a pic of the pollinated flower, showing the stigmatic wings completely folded over the stigma:



This is the kind of thing about orchids that just fascinates the hell of me--these reproductive mechanisms they use to ensure their survival.

But beyond this, the fact that this particular flower actually accepted this pollen raises many further interesting questions.

The pollen came from that Eulophia keithii I sent to Sue, a plant that belongs taxonomically in a completely different subtribe (Cyrtopodiinae) than the Miltonidium pod parent here (Oncidiinae). While these kinds of inter-tribal crosses *can* sometimes occur, it's generally accepted that they won't be successful.

Assuming this cross "takes" and produces viable seed (just because a flower gets pollinated does not mean the cross has been successful: the seed, if any are produced, has to sprout, and the seedlings have to actually grow past the corm stage into adult plants--many crosses don't get past the corm stage before the seedlings all mysteriously die), was it because Eulophia was placed in the wrong taxonomic group? Is Eulophia not specialized enough--is it "primitive" enough--to breed with a diverse range of genera? Or is Mtdm., being an intergeneric hybrid, "muddy" enough genetically to accept pollen from genera completely outside the subtribe of its ancestors?

I just don't know.

But it'll be interesting to see how this one turns out!

Cool stuff, in any case.

[mde]

Wow, very cool. I've never even ventured the possibility of breeding and pollinating, but enjoy learning about it as the bug may hit me sometime. Right now I think I'm too impatient. I want immediate gratification! Thanks for the very interesting thread. Keep us posted.

Matt

[orchidaddict789]

That's very interesting! That's a great observation--proof that orchids are very smart plants indeed . hmmm, a eulophia and miltonidium--interesting cross. I wonder how it will turn out...hope it's successful!

[Gilda]

Thank you Louis !!~ I love stuff like this ,too. Never knew that happened and in a matter of hours..too cool !
Did you happen to see the Nature program on PBS about the Brazil Nut tree? Well, it seems that they found this waspy fly is the only pollinator of it and guess what the male fly does to attract a female ??? Give up ??? He wallows all over this orchid to get the perfume or the female is not attracted to him...soooooooooo no orchid ,no fly , no Brazil nuts ! Just grand huh ?

[TundraKev]

I really love this stuff too. It's very cool to actually have someone explain the whole process with photos to boot. Thanks much. Do more of this stuff.

Kev

[sadie]

Wow! That is an amazing change -- and so quickly after pollination. Thanks for the interesting info and pictures to boot!

[LJA]

Hey--you're all welcome! I like doing posts like this when I have the time to put something together--glad you enjoyed it. I'll update here as things progress (or don't).

[bench72]

This is kewl! It's like an orchid drama mini series and well you know how I love those... fingers crossed that the love between Cleo and keithii 'blossoms'..

[Piper]

Orchid sex!

Porn, porn, porn!

Julie

PS - Nice one, Louis - thanks!

[shalene]

Very interesting and your photos are wonderful!!! Thanks for doing this for us. I don't have the room or the patience at this time to get involved with breeding but it is very exciting to hear and read about everyone's experiments.
Thanks again,
Shalene