Wednesday, July 8, 2009

Fern cultures

Several people have written to me for information relating to fern spore cultures. I am not an expert at this phase of micropropagation and have only a vague familiarity with this type of cultured plants but here is what I do know. Hopefully it is of use to you.

Although there are currently at least 20 different species of ferns which are found here in America, I would venture to say that the same process could easily work with any of them. So without any further wait here is the information.

The fern spores are usually collected in the late autumn from mature fern plants. We will use the domestic “Platycerium superbum” as an example. The spores would naturally have to be sterilized and this is usually accomplished by way of a centrifuging technique. The spores are quickly shaken in a test tube using sterile water with a couple of drops of Tweeen 20 added. If you have access to a centrifuge you could place the tube in it and rotate it at the rate of 2800 RPM for 5 minutes. This will settle the spores to the bottom of the test tube. Next, discard the liquid in the tube and replace it with clean sterile water. Once again shake and let the tube sit at room temperature for a 24 hour period.

The following day re-centrifuge the tube and discard the water again. Now add 10ml of common household bleach. Let the bleach remain in the test tube for approximately 5 minutes. Finally, centrifuge again and discard the solution and place the aseptically clean plant spores into a media as described below.

These spores you will note were planted into the media without a final wash with sterile water. The cultures were then incubated for 16 hours. The temperature should be kept at about 25 degrees C.

This is a slow growth method and your spores will start to germinate and produce prothallus in about three month’s time. You will likely need to sub-divide these early cultures as they start to form. In a future article I shall cover construction of a home made centrifuge as well as an incubator.

This media should be successful for just about any fern cultures that you wish to try it on.

300 mg MS salts
500 mg NaH2PO4
5 mg Inositol
20000 mg Sucrose
8000 mg agar

Copyright @ 2009 Joseph Parish