Cattleya Protocorms on Bark

[Anglo]

Yes, you should have an update.

The bark experiment failed. The protocorms on either end in the first picture turned a darkish green color and died. The one on the left went first and the one on the right died about three days ago. I’m not sure if the problem was a pathogen or a nutritional deficiency or both. The protocorm in the middle remained healthy looking on the bark, but stopped growing. Now, the experiment is to see if a protocorm out of the flask can be saved through some other method.

Plan B was an attempt to sterilize the protocorm and put it back into a flask. That failed very quickly, as you might have guessed. I gave the little guy a short bath in hydrogen peroxide, rinsed it in sterilized water, and then put it in a new flask by itself. In less than 48 hours, there was a white, slimy fungus growing around its base.

So I took it back out of the flask, destroyed the fungus, and began Plan C. That’s been underway for about three days. It’s an intensive care program that involves feeding and watering the protocorm by soaking it in nutrient solutions. In between, it sits on damp Sphagnum moss under fluorescent light. This is a modified Sphag-and-bag approach.

Oh, and the fungus. Aside from using chemical fungicides, there’s a great organic fungicide that is rarely if ever mentioned in the orchid world even though it’s pretty well known in organic gardening. It’s Trichoderma, a fungus itself, but one that kills other fungi. Maybe I’ll do a post on that in the Pests & Diseases section.

[Royal]

Thanks for the update, and sorry it didn't work out. This is a great example of how in vitro propagation is far superior to ex vitro or symbiotic approaches. Granted, one may achieve some measure of success, but when you compare percent germination and survival rates it is no contest.

In other words, it might be possible to get a few p-corms to survive with some special efforts but it's hard and would take a long time. If these efforts where directed towards in vitro culture, chances of success go up dramatically and the yeild in the end would be 100-fold.

[Undergrounder]

Yeah but in vitro has its own problems, sterility requires a little bit of equipment and practice and not everyone can do it.

I got protocorms to grow for about 3 months on perlite in flask with a bit of water down the bottom forming a reservoir S/H style. It worked well, and you could open up the flask, take photos, close it back up, no problems.

But the solution i was using was only normal fertiliser and i didn't put in a lot of effort to make it work. But growing protocorms on perlite definitely seemed possible. And sterility isn't needed.

The biggest problem with that though was it was impossible to transport because the perlite would roll around.

[Des]

Royal is right ,germinating orchids the in - vitro method is the way to go .
After perfecting your methods it is really like falling off a log ,you just get it right all the time and it soon becomes "old hat".
That is why I enjoy experimenting on differing methods, it is the excitement of finding out something new, going were no other has gone , this is why the human race is so successful, because there are a few who are prepared to think out of the box and on rare occasions find something new !!
So don't give up until you get to the stage that you are convinced that it will not work

[Undergrounder]

I think when i get a flow hood i'll give it more of a serious effort. But with my glove box i barely get 50% non-contamination and i don't want to risk my better crosses until i get better.

[Royal]

50% is pretty darn good. I bet you could figure out the cause and find a simple fix and get to less than 10% contamination without much work.

Still, take any seed capsule. Let's say it has 1000 seeds (very conservative estimate). If half germinate, you've got yourself a bunch of seedlings. I guess my point is that germinating orchid seeds with any method will require some degree of work and ingenuity. Focus that work and ingenuity on the the right process and the results will speak for themselves. Experimentation is important, but how one interprets the results is of equal importance.