Friday, January 08, 2010
How Orchids Start
Orchid protocorms on agar media. Orchid seed is very fine and has no notable cotyledon/food matter to support it in the first days of growth. For example, on a lima bean or a peanut, you have two starchy halves (dicotyledon; orchids are monocots) or in corn, a fleshy kernal surrounding the tiny plant start. In contrast, orchids depend on a symbiotic fungus to provide initial nutrients. However, in artificial cultivation, better yields were achieved by putting the growth nutrients into sterile agar media, bypassing the need for a fungus culture.
In the photo, the little green spots are new orchid protocorms starting to germinate. In some crosses, you may end up with thousands of protocorms. However, the more dissimilar the parents (different genera, for example), the less plants/protocorms that will germinate. This cross ended up with only a few protocorms which is perfectly fine for me but perhaps not great for commercial growers who need volume.
Too nerdy or kind of interesting? Thoughts?