For my first attempts at zinnia tissue culture, I used the conventional Murashige and Skoog (MS) formula for the medium with added sugar. Benzylaminopurine (BAP) was added as a plant growth hormone to stimulate shoot formation. (The strategy is: first the shoots, and then the roots.) I also included some PPM (a proprietary Plant Preservative Mixture) to help prevent fungal and bacterial contamination.
This is all standard stuff in the commercial "Kitchen Culture Kit" http://www.kitchenculturekit.com/index.htm for amateur hobbyist tissue culture, and is known to work for getting shoots from African Violet leaves. I don't know yet if it works for zinnias, but I have put some small pieces (called "explants") of zinnia tissue on some of the medium to see what happens.
So far, nothing much, as you can see in the picture. I may have killed the zinnia tissue during the "disinfesting" stage, in which I treated it the same as African Violet leaves, and swished it briefly in 70-percent alcohol followed by a 30-minute soak in 10-percent bleach, followed by a rinse in distilled water, and then placement on the agar-gelled culture medium.
I used denatured ethyl alcohol, because I didn't have any non-denatured ethanol, and that may have been harmful. I may have left the tissue too long in the bleach. Lots of variables to experiment with, include different things to use to disinfect the explants, and different ways of taking the explants. I will continue my TC experiments this Winter with explants taken from my cutting plants. In the meantime, I will be taking more cuttings, before my zinnias get killed by a freeze.
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