For those of you who have heard the term, but never seen the animal, this is what protocorm proliferation looks like. For those of you who are no confused, I shall define as best I can.
Protocorm: This is the primordial bit of tissue that forms as an orchid seed germinates. The initial thing is a little ball of undifferentiated tissue (tissue who's function is undetermined and can generate any part of the plant) that after a couple months starts forming wee leaves and then roots.
Protocorm proliferation is a phenomena where the protocorm replicates itself like a stem cell forming what is called a callus in plant tissue culture. I can't explain why it happens as I don't know. Generally in tissue culture we make them with application of excess hormones.
Personally, I've seen this most often in Phalaenopsis flasks, but it can happen with any genus. Such structures will not survive outside the flask. However, they can be divided and continued in flask until they grow normally. This results in clones since the replicated protocorms from a clump are identical. This is generally how the only successful paph clones are made. The downside is since you're starting with seed, you might find later that you've propagated a plant that has dopey flowers.
Veggie Folk has reservations about this.
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