Unusual morphology

When most plants are flowering the bud sites alternate, with the first two branches opposite each other, then another two each facing 90 degrees from the last set. However, there’s my Durban x Skunk. It has three bud sites at each node, going all the way up the cola. My other plants don’t do this. Any ideas about this?
Trau,
Austin, Texas

The Durban-Skunk is growing three branches because it is following the directions in its genetic code. The unusual characteristic is most likely the result of either a rare genetic recessive allele (a particular version of a gene), or a mutation.

Let’s say the allele for three branches is recessive. If it is paired with an allele for two branches, which is dominant, only two branches will be produced. A plant would only grow three branches if it had two alleles for three branches.

If the three-branch allele plants were crossed with a plant that has two branches per node, then the first-generation (F1) progeny would all have two branches. However, if these F1 plants were crossed together, about a quarter of the resulting progeny would have three branches.

Mutation is another possible explanation for the three branches, although this is much less likely. Somehow the gene(s) for number of branches got mixed up in replicating and this plant is a result.

I have occasionally seen Colombian plants that started out the same as yours with three branches per node. However, after growing several sets of leaves the plant spontaneously grew two sets of top leaves resulting in two equal sized branches. Each node supported two leaves growing on opposite sides of the branch.

I have some questions. Does this plant have a higher yield than its sisters do? Do each of the branches produce buds of weight equal to a comparable but two-branched plant? Is the quality of the high maintained?

Even if the plant yields less than its sisters do, this novel and unique characteristic could be used in a breeding program that would include increasing the size of the buds. Whether the morphology is the result of a mutation or just a set of recessive genes getting together, this plant should be preserved and propagated by cuttings as well as sexual reproduction. If the plant is crossed with another plant and the gene is recessive, F1 plants will not have this characteristic and they’ll be quite uniform. However, the next generation, the F2 plants, will vary in characteristics as the alleles sort themselves out in myriad combinations. Some of these plants will probably have three-branched nodes. If two of these three-pronged F2 plants are crossed, their progeny most likely will also have three branches.

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