Pods and Seeds
I decided to water the greenhouse very early this morning . It was lovely and cool at 6.30am compared with yesterday afternoon’s 40 degrees, in Cool Asia. I don’t think the Coelogynes and Dendrobiums mind too much as long as they had plenty of water.
Whilst watering I always look for pests so that anything can be eradicated quickly before spreading about the greenhouse but today I was struck by the beauty of seed pods.
Another job whilst watering is to check that the pods have not started to split. If they have the seed has to be collected, put in an envelope and placed in a shoebox to dry. Our lab is warm and dry just right for drying seed.
The seed pod shown below is Sobralia macrantha. It is large and will hopefully have millions of seed in it for us to sow in our lab.
Our lab window sill houses a small display of dry seed pods and orchid seed. They come in many different shapes and sizes.
Orchid seeds are the smallest seeds in the world. Unlike seeds from other plants, orchid seed only contain an embryo. There is no carbohydrate to aid the start of germination. Orchids are dependent on mycorrhizal fungus to provide the necessary sugars for germination. Without the fungus the seed cannot germinate.
The lack of any baggage with the embryo makes the seed extremely light, ideal for wind dispersal. Seed can travel a long way from the parent plant. The photo below show tiny seeds on the sides of the glass jar.
Our lab sown seed is not dependent on mycorrhizal fungus to germinate because the media we use contains sugar to feed the embryo. It takes at least two years for one of our tiny species orchid seeds to become a viable orchid.
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