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 How Adaptable Are Orchids? 
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Joined: Thu Dec 23, 2010 11:41 pm
Posts: 124
Location: Glendale, CA, USA
Post How Adaptable Are Orchids?
I started composing a post on the topic but it quickly grew into a blog entry. Let's see how well I can get to the heart of the matter.

My Epc Cerina 'Nadia' has a big seed pod on it...

Image

Hopefully it's the result of pollen from this cross by SVO...

Epi (Pacific Eclipse x Pacific Canary) ‘Yellow Sun’ x Epi magnoliae

Would you be happy if I split the seeds with you? Or would you prefer to shell out $50 bucks to buy Cerina on eBay? Would you more highly prefer the seeds if you knew for a fact that they could germinate without fungus/flasking?

Let's imagine that I do split the seeds with you. We won't have the same exact germination rate for various reasons. For example, our temps will be different.

We'll keep it simple and say that, out of 1000s and 1000s of seeds, we each end up with 50 seedlings. The question is, how well adapted are the seedlings to our conditions? We could find out by exchanging half of our seedlings with each other. In your conditions, the better that your seedlings did compared to my seedlings, the better adapted that your seedlings are to your conditions.

So the more adaptable the cross is, the more beneficial it is to grow it from seed. You are more likely to end up with an orchid that does much better in your conditions.

Maybe some numbers will help?

Say that the optimal temp for Cerina is 85F. You grow your orchids inside your house, where the temp is 78F. If the optimal temp for all the seeds/seedlings of Cerina x SVO's orchid is also 85F, then as far as temps are concerned there'd be no benefit to growing it from seed. But what if the optimal temp for the cross ranges from 86F to 84F? For some seeds/seedlings the optimal temp is 86F, for others it's 85F and for others it's 84F. In this case there would be a very small benefit to growing it from seed. The larger the range of optimal temps, the larger the benefit.

Growing the cross from seed is like casting a net. The more adaptable the cross, the bigger the net, which means catching a better orchid.

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Carlos - Epiphytes and Economics


Wed Sep 06, 2017 7:53 pm
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Joined: Thu Feb 23, 2017 3:46 pm
Posts: 47
Location: Middlesex, UK
Post Re: How Adaptable Are Orchids?
You can't grow orchid seeds as you do other plant seeds
They are really tiny, and aside from the genetic material for the new plant, the seed has no nutrients.

In the wild the seeds develop symbiotically with fungi which provide nutrients for the seedling on germination.

In cultivation, orchid seeds are grown in-vitro, a process beyond most growers.


Thu Sep 07, 2017 7:39 am
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Joined: Thu Dec 23, 2010 11:41 pm
Posts: 124
Location: Glendale, CA, USA
Post Re: How Adaptable Are Orchids?
ArtV, you're correct that orchid seeds lack the nutrients that they need to germinate on their own. However, this rule has at least one exception... reed-stem Epidendrums. Their seeds do have endosperm (built-in nutrients).

How did reeds end up being exceptional? We know that the earliest orchids all must have produced seeds with endosperm. We know that at least one orchid began producing seeds without endosperm. We know that this turned out to be a very successful strategy because now nearly all orchids produce seeds without endosperm.

So does this mean that reeds produce seeds with endosperm because they are really primitive (old)? This would be surprising since reeds can be crossed with non-reeds. Vanilla is a primitive orchid. But even though it's so old, I'm guessing that its seeds don't have endosperm. Vanilla certainly can't be crossed with newer orchids. So it doesn't make sense for reeds to be older than Vanilla, but have the ability to cross with newer orchids. But if reeds were not among the earliest orchids that produced seeds with endosperm, it means that the earliest reeds produced seeds without endosperm. Which would mean that reeds started producing seeds with endosperm.

How funny is that?

Earliest orchids: Our seeds need their own nutrients.
Rule breaking orchid: That's not true.
Subsequent orchids: Our seeds don't need their own nutrients.
Rule breaking reed: That's not true.

It takes more energy for an orchid to produce seeds with endosperm. Plus, it makes the seeds larger and heavier. So less of them can be produced and they can't travel as far. The only way it would be advantageous for an orchid to turn around and start producing seeds with endosperm is if there was a shortage of helpful fungus. Evidently this was the case for reeds.

To be clear, I've never sown sterilized reed seeds on sterilized media in a sterilized environment. So it's certainly possible that my reed seeds have germinated thanks to a helpful fungus. But take a look at this photo of some reed seeds after one night of soaking in water...

Image

Unfortunately, I did not include some soaked non-reed seeds for comparison. They would have been a lot smaller. And a coconut would have been a lot larger. Why is a coconut so much larger? Because its embryo is so much larger? Why would its embryo need to be so large? Why would a coconut have so much more genetic material/information than an orchid seed?

Seeds aren't different sizes because of different amounts of genetic material. They are different sizes because of different amounts of nutrients. A coconut is so much larger than a reed seed because the coconut has so much more nutrients. By this same token, a reed seed is so much larger than a non-reed seed because the reed seed has so much more nutrients.

The main thing that I'm trying to figure out is when the seeds of crosses between reeds and non-reeds have endosperm. The SVO orchid is a cross between a reed and a non-reed. The seeds of the reed mother do have endosperm. I'm guessing that the seeds of the non-reed father do not. So will the seeds of the cross have endosperm?

It's super convenient to be able to germinate reed seeds without fungus/flasking. The problem is that reeds aren't the most exciting orchids. It would be ideal to try and cross them with non-reeds in order to develop a line of exciting orchids that can be easily grown from seed.

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Carlos - Epiphytes and Economics


Thu Sep 07, 2017 10:59 am
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Joined: Wed Oct 31, 2007 5:52 pm
Posts: 7576
Location: Hayward- S.F. Bay area Ca.
Post Re: How Adaptable Are Orchids?
Carlos I saw a photo of a fantastic species of Orchid,Thelymitra speciosa. From dry western Australia. Something to look for in California? Or the world of orchid people?


Mon Sep 11, 2017 12:57 am
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Joined: Thu Dec 23, 2010 11:41 pm
Posts: 124
Location: Glendale, CA, USA
Post Re: How Adaptable Are Orchids?
Stan, I've never seen it anywhere for sale or in any collections. Recently I watched Aussie Gold Hunters on Netflix. Didn't see it in any of the scenes.

Maybe the most similar orchid that I ever had was Pterostylis curta. Somebody gave me a few but I'm not sure what happened to them. Usually I don't do so well with deciduous bulbs. I see an empty pot and think, "Might as well put it to good use!"

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Carlos - Epiphytes and Economics


Mon Sep 11, 2017 7:03 pm
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