Quote:
Originally Posted by orchidsarefun
but just be prepared for disappointment.
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This can also be said if anybody tried in-vitro methods as well, let alone ex-vitro methods.
I've had entire batches of seeds that were not viable or just all of a sudden get contaminated even after a week of showing no signs of problems.
Many orchids produce hundreds to millions of dust-like seeds for a reason...
It's a numbers game for them.
You must
more often than not depend on a failure, but be prepared for the relatively few successes that occur, and take those successes to the finish line as best as you can.
Survival rates even amongst seedlings that are ready to be deflasked can sometimes be very poor as well.
I've personally lost 100% of seedlings that were ready for deflasking either immediately upon deflasking or shortly thereafter, with numbers that can continue to dwindle even several months past the date I deflasked them!
Quote:
Originally Posted by orchidsarefun
I have read about seedlings germinating outdoors on orchids mounted on palms, obviously not in sterile conditions. Orchids' natural habitat is not sterile either.
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Yes, you're correct, an orchid's natural habitat is
not sterile. Germination of orchid seeds via non-sterile ex-vitro methods is possible, but oftentimes under very specific criteria...
Cattleya seeds have been germinated on the mounts of the parent plants out in the open, but, again, they were done under a specific set of circumstances. Those Cattleya seeds were germinated on the mounts of the parent plants that were growing in greenhouses of owners who were located in the South American or Latin American countries from which Cattleyas can be found in the wild. And even when I mention this, it will seem a little vague as to why I would even care to go into such seemingly miniscule and deceptively insignificant details.
And then there's the Thomas and Lotte article where they went into the woods and collected some bark and surface sowed some seeds of an Epidendrum where germination occurred. Again, I really encourage you to look into this article more in depth. Notice how the specifics are not even remotely mentioned in the article. I bet if you tried the same thing just arbitrarily, it'd be a hit or miss.
Part of science is to be able to replicate an experiment with a relatively high amount of reliability, I bet you it'd be very difficult to replicate what the article in the Thomas and Lotte article mentions just based off of the amount of information they provide. Like I've said before, and like someone else before me told me, the Thomas and Lotte articles should be read with a grain of salt, mostly because they are far too over simplified!
While sowing orchid seeds using ex-vitro methods under specific circumstances can be possible, it is not highly reliable. Nor will the yield of seedlings be guaranteed (and what I mean is that there is no guarantee that
any protocorms will survive to reach the seedling stage at all).
Quote:
Originally Posted by orchidsarefun
However, I think the problem we have is that there are so many types of "foreign" airborne fungi/molds/bacteria/mites in the home and greenhouse, that its impossible for a tiny seed to grow on - it will be on the bottom of the food chain.
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You are right, but I think you might be missing some important details that will help you understand where
I'm coming from. And believe me, it is
not as simple as what the Thomas and Lotte article makes things out to be...
If you look at an orchid seed under a microscope, you will quickly find that structurally speaking, these things are deceptively simple...
You have the outer layer, which is the
testa. It basically looks like candy wrapper.
Inside the testa, you will see the embryo. But what you don't necessarily see is a thin layer of tissue that envelops the embryo called a
carapace.
Depending on the orchid species, some species of orchids have seeds that have a meager few cells of what is called
endosperm on one of the poles of the embryo also encased inside the carapace. Think of endosperm as the orchid embryo's yolk sac.
A large majority of orchid seeds DO NOT have this endosperm to get them through germination on their own! Hence why they rely on specific mycorrhizal fungal symbionts to penetrate the seed's testa and carapace in order to provide the nutrients the embryo needs to begin the process of a successful germination. The mychorrhizal fungi that many orchid seeds rely on are in the complex of fungi collectively known as Rhizoctonia.
The orchids that have seeds that do contain a tiny amount of endosperm are the species that I mentioned! And those are the ones that are easily germinated without the aid of any mycorrhizal fungi or sterile in-vitro methods. It is a time tested theory that will hold up under fire!
For example, I have personally surface sown seeds of
Bletilla striata on potting soil and have obtained a fair amount of germination and green protocorms. However, raising those protocorms to seedlings was something I have never achieved yet at the moment.
This is just barely scratching the surface of the complexities of growing orchid seeds in general. Obviously some orchid seeds are easier to germinate than others, but I also encourage that these matters not be over simplified.
If you'd like to read more about this
complicated process, I encourage you to dig through
Google Scholar for real peer reviewed scientific articles.
Although, I will say that the process of germinating orchid seeds via in-vitro methods don't actually need to be terribly complicated. But it definitely helps to understand the rather intricate details of the process in which an orchid seed germinates to grasp why asymbiotic in-vitro micropropagation methods are the preferred way of growing orchid seeds.
Like I said, The Orchid Boy is more than free to try things out, but realize many people have walked a similar path before him, and I would like to impress on him to do much research and think realistically about things. If he does end up succeeding with what he wants to try out, I do highly encourage his posting his successes, as that is a major contribution to the orchid community in general (regardless of whether it is appreciated or not).
Growing orchids from seed a little differently
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