If I keep cloning plants and then taking clones from clones, will the clones remain potent, or is there a slide in potency? Can you clone a plant only so many times before it becomes weak?
Clones and clones from clones retain their potency. Single lines have been reproduced asexually by cloning for more than 20 years with no loss of potency or odor/taste.
Yet the question of genetic drift over many generations is not unreasonable. Mutations occur on a regular basis in asexual as well as sexual reproduction. Genetic researcher Barbara McClintock has discovered that genes jump around on chromosomes, and recent studies have proved that they also jump from plant to plant. Any change in gene patterns, whether the gene is on the chromosome or has broken apart and lost or gained material, results in changes in the plant. Thus the variety can gradually shift over a period of time.
Clones propagated over many generations along separate lines will look slightly different. Perhaps the answer is to preserve the mother plant for as long as possible ? but even a single plant will exhibit some drift. Remember that during sexual reproduction mutations are more likely to occur than during the asexual reproductive process of cloning.
Viruses sometimes attack cannabis. They can affect the plants' health, growth and potency as well as affecting the genetic makeup of the plant. Once a plant is infected with a virus, it can never recover. For that reason, more than one plant of a special line should be maintained.
For all its faults, cloning plants is the best way to preserve a plant's particular characteristics with the fewest genetic changes.