Orchid Naming for Dummies

[Tikva]

WOW it must be said that I've never had it explained to me in such detail. I knew some of it and some of it was new or better explained to where I didn't say "screw it Wolf like pretty flower, wolf buy flower" LOL Thanks for the details Julie... hope the finger feels better.

Wolf

Ditto! Tikva thinks it's pretty and inexpensive, she buys it and wants it to live...
Julie - amazing info! I am thinking of a way to bribe you to come up and have a look at my newest obsession. LOL! You must really be an expert :c)

[Gin]

Good idea Tim ! I could type it ... fast typer but letters come out backward . Gin

[Piper]

LOL - I've seen you type, Gin!

There's a dagger between your teeth on a good day!

Julie

[Piper]

Diane has raised her hand and asked an excellent question.

Not bad for a bird brain...

When a cross is listed, the first parent named is the pod parent. That's the mommy plant that actually produces the seed pod. The second parent is known as the pollen parent. That's the daddy that donates his pollen and then goes and hangs out in bars with his pals.

Plants usually inherit more of the traits of the pod parent. Which is good, since daddy is a bar fly... So breeders select the pod parent appropriately. Switching pod parents in a cross would definitely influence the flowers produced. Yeah, Junior would start hanging out in bars... And don't forget plant size - many crosses seek to produce either larger or more compact plants.

Diane is asking if the cross A x B and the cross B x A, would keep the same grex name. I honestly don't know. I assume so, because I've never heard otherwise. Anybody have an answer? And if the answer is no, can you give an example of different grexes where the pod parents are reversed?

Julie

[Hoa Tony Nguyen]

Great article! And Nice writing, Julie! Are you having a lot of time to burn?

Regarding the question whether a switch in pod/pollen parent would merit a different grex name, I believe that is not the case. I have never heard that by interchanging the pod or pollen parents, a new grex can be created. Lot of times, interchanging the parents would not result in any significant difference in the progeny although in certain cases, it does since the pod parent does contribute more than just its share of the nucleus chromosomes. I believe that in higher plants (the angiosperm group that also includes the orchid family), the two cellular organells with their own DNA, i.e plastids and mitochondrias are inherited from the mother (the pod parent), hence the rational for changing the pod parent in hope of improving the cross. Maternal uniparental inheritance of mitochondrial and chloroplast genes appears to rule the day in orchids although there might be exceptions, i.e. the possibility of paternal inheritance (remote chance) or biparental inheritance (strong chance) does exist. These studies are very hard to conduct for orchids and I am aware of only a very small number of studies for a few orchid species.
From a geneticist's point, the extra contribution from the pod parent is not significant enough to warrant creating an entirely new grex (in orchids, that could be a whole new genus).
Cheers. Hoa.

[Piper]

Very interesting, Hoa - thanks! I wondered why the pod parent had more influence.

Oh, all this talk of mitochondria got me so excited! ...I'm a tad exciteable too...

I wanted to post some home pictures of mitochondria I once knew. The photo below shows a rod and a cone from a frog's retina. Rods and cones are the light sensitive photoreceptors in our eyes. Their structure is pretty uniform for animals, so ours would look similar to these.

Cones detect different wavelengths (ie, colors) of light, and rods detect very low levels of light. That is, cones are less exciteable. This is why you don't see colors at night (not enough light for the cones to fire.) It's also why you see very faint stars better out of your peripheral vision. The fovea (or center of your retina) is packed with more cones than rods, but the more light sensitive rods predominate the outer edges of the retina.

Anyway, back to the picture. The upper halves of these cells are made up of stacked layers of membrane that contain the rhodopsin - that's what reacts to light energy and starts the nerve signal to the brain. (The membrane stacks resemble a tall stack of poker chips.) You can't see the layers in this picture, because they're so densely stacked. The lower halves of the cells produce all the energy to send the nerve signal, manage things, and grow more membrane stacks. So the lower segments contain all the mitochondria. Those are the squiggly round things in the lower parts of the cells.

Oh yeah, ROS means Rod Outer Segment (the membrane stack) and COS means Cone Outer Segment. This pic was taken with a transmission electron microscope at X 6,300 magnification.

This is how I misspent my youth...

Julie

[Hoa Tony Nguyen]

Amazing picture, Julie!
So you know how to take picture with the electron microscope, eh! So what did you do with your youth that required the usage of these intruments? Graduate student? I don't operate these instruments myself but I do use them for our work at times. I am planing a project involving these photoreceptor cells but they are very difficult cells to cultivate. Do you know how to extract them from embryos?
Cheers. Hoa.

[Piper]

This was my senior thesis as an undergrad. After I graduated I spent some time working in a lab at Dartmouth Med School cultivating cow retinal epithelial tissue. We were studying the vascular breakdown associated with diabetic retinopathy.

I've worked with frog, rat, cow and human eyes, but never embryos. That would be tough. Although...the changes that lead to diabetic reinopathy are caused by retinal tissue reverting to embryonic behavior. That is, where lower levels of oxygenation stimulate vascular growth. Trouble is, for the diabetic, the new vascular growth isn't sound, and the blood vessels tend to rupture easily - causing the retinal bleeds and blindness.

Too bad the researcher was such a hack. The work was fascinating.

What do you do, when you're not sniffing floofy blooms, Hoa?

I'll post some scanning EM (electron microscope) shots. They're very cool.

Julie

[Diane]

OKAY - THIS HAS GOTTEN WAY OUT OF HAND!!!!

Enough of the scientific jargon fest!!

Sheesh - whatever happened to pretty pictures????

[Hoa Tony Nguyen]

Hi Julie,
Let just say that I make my living doing science and related stuff. In time, I will fill in the details. Sounds like your undergraduate training is biology or related field. Fascinating stuff.

Cheers.
PS. Now now Diane, don't you enjoy our recent posts? At times, we need to elevate the IQ levels of the conversation to spice up the pretty pictures...