Redneck Orchid Flasking

[quiltingwacko]

I dunno. There has been some pretty scary mold in my kitchen!

[vmax3000]

Originally Posted by quiltingwacko

I dunno. There has been some pretty scary mold in my kitchen!

[korxi]

In the wild the fungus provides sugar for the seed. This is needed for it to germinate since it has no nutrients stored.

In home/kitchen flasking the agar solution is not used to attract mold or other funghi since they would actually kill of the seeds. Instead it provides the sugar that the fungus in the wild would provide, hence making it possible for the seed to germinate.

Christian

[Royal]

Exactly, Christian. In the wild, a fungal root symbiont, or mycorrhyzae, will (given the right conditions) provide a constant source of simple sugars to a germinating orchid seed.

Since orchids grow very slowly, it may take weeks or months for a seed to develop enough to turn green and photosynthesize. Unlike corn and rice, there is no stored energy source so the protocorm must have an external source. The 'fungus' is this source. It's not really a visible fungal growth, just an association between a certain type of fungi and the germinating orchid seed whereby the seed is nurtured by the metabolic byproducts of the fungi.

Growing orchids in axenic culture is possible, but the developing orchid will still need an external energy source. The nutrient media is the source of simple sugars. The agar is only for solidification of the media, it provides minimal nutritional value (maybe a little Calcium). Some use liquid media alone (without agar) or other solid surfaces (filter papers) saturated with liquid nutrient media.

This is where mold enters in the equation. Nutrient media is a sugary, nutrient rich substrate - perfect for growing mold, bacteria, algae, and sometimes orchids. Any contamination will usually spread through the whole flask quickly, killing everything else. Normal healthy flasks do not have any mold or fungi in them. Maintaining sterile conditions is of utmost importance. This is why we must disinfect the seed. If it's been exposed to the air - it's contaminated.

[Undergrounder]

Originally Posted by RoyalOrchids

... The 'fungus' is this source. It's not really a visible fungal growth, just an association between a certain type of fungi and the germinating orchid seed whereby the seed is nurtured by the metabolic byproducts of the fungi...

oh yeah its visible all right, it looks like a rhizamorphic strand spreading out over the seeds like any other fungus looks like.. i have a good photo in one of my books of it actually spreading over seeds (via the turkish towel method) but this is what it looks like on agar:



(Picture from Sydney Uni mycology dept. website)

Actually that's a very good website to go to for information on orchids mycorrhizal partnerships

[Royal]

Ok, so you can see it on a back-lit petri dish. I guess I should have clarified. In nature, it won't be visible as a fugal mat. You won't see a big mass of fungus with germinating orchid seeds on top.

Most hobby orchid propagators are not inoculating their cultures with mycorrhizae. I was just trying to clear up some misconception about the difference between mold in flasks, and mycorrhyzae. Neat photo though, and good input.

[vmax3000]

Do I owe anyone tuition for this crash course in micro?? Actually, I have really enjoyed the thread! Just an FYI....I tried to fertilize the M. xerophytum, today. So, all of this will come in really handy, if a pod actually sets!! I will have to research pod ripening and seed sterilization techniques, if I am lucky...and, no throwing away the pod this time !

[Undergrounder]

yeah well its not like a mat, its more like a web.. im surprised noone's heard of the turkish towel method of orchid seed germination, my father used it to grow Dendrobium speciosum that way...

basically a wet towel with orchid seeds sprinkled on top and a few cut tips of the doner orchid's roots as well.. the fungus rhizomorophs actually reach out from the roots and spread over the towel from seed to seed like strands of a web..

[kavanaru]

Originally Posted by Undergrounder

yeah well its not like a mat, its more like a web.. im surprised noone's heard of the turkish towel method of orchid seed germination, my father used it to grow Dendrobium speciosum that way...

basically a wet towel with orchid seeds sprinkled on top and a few cut tips of the doner orchid's roots as well.. the fungus rhizomorophs actually reach out from the roots and spread over the towel from seed to seed like strands of a web..

interesting... can you please explain better the method? The towel was wet with just water r something else was added? Do you know how long it takes until the little plants could be transferred to culture medium?

[Undergrounder]

sorry erm yeah that's the basic version..

umm

OK a less basic version is:

you get a damp ball of sphagnum moss, rap a towel around it, put it in a pot, sprinkle the seeds on top, add the roots, spray with a mister, put a piece of glass on top, and then pray.

BUT there's more to it than that, ie: everything needs to be fairly well sterelised, and there might be some fertiliser involved etc. ill find out for you

Edit:

OK, less basic still:

1. wash and sterelise the pot, glass, etc. in 10% clorox (bleach) water.. boil a piece of cloth to sterelise it
2. wrap some -peat- moss in a towel, about the size of a baseball.
2a. Dip the peat moss / towel ball in clorox solution, then wash it off and boil it throughly (don't leave any clorox on the final germinating surface or it will kill the good fungus)
3. put the clean, sterelised wrapped peat ball in the base of the pot.
4. surround the edge of the ball (the space between it and the pot) with clean -sphagnum- moss.
5. sprinkle the seeds on the surface of the ball.
6. sprinkle the roots from the parent plant on the surface of the ball (don't sterelise those!)
7. Spray with a fine mister
8. Place the clean glass on top of the pot
9. Place the pot in the shade
10. The fungi spreads out from the roots to the seeds
11. After a few weeks the seeds develop into protocorms
12. The protocorms develops leaves
13. After the second leaf add 1/20 strength fertiliser with an eyedropper or very fine mist (sterelise the ferts solution as well)
14. Repeat ferts again after about 3 months
15. After about a year total, remove the glass occasionally to harden off the little seedlings
16. Transplant the tiny seedlings to the equivalent of a compot, but obviously for smaller plants, so shallow dish
17. After about 2 years they should be the equivalent of normal flaskling size plants.