Phenotype = Genotype + Environment
Updated: Mar 3, 2020
Why would clones look so different?
The two pictures on the left are of the same individual, and the two pictures on the right are of the same individual. They were cut from the same mother so they are genetically identical, and they were in close proximity (about four feet apart) in a 6 x 10 foot greenhouse, in the same soil. The phenotype (physical characteristics) are very different, and the flowers had different chemotypes (chemical profile), but the genotypes are identical. That means that something in the environment has caused the resulting differences, right? But they were grown in very similar conditions, although one plant was closer to the door. Could slight differences in airflow have such a big impact on the phenotype? Maybe.
Genetic expression response to environmental changes is highly understudied, especially in asexual and clonal organisms. Clonal organisms have the same genetic information, so changes in genetic expression are probably not mutations, but rather could be temporary changes which allow rapid adaptation to environmental changes.
Plants, unlike most animals, don't have the ability to move when conditions are stressful. Stress could come from changes in temperature, water light, nutrients etc. and plants respond to stress the only way they can which is to alter gene expression and pray to sweet baby Jesus that the changes help them get through the stress and make it long enough to reproduce. This can result in what is referred to as phenotypic plasticity- changes in the phenotype in response to the environment. What if the cloning process- cutting bits off the mother- is stressful, for both the mother and the propagules?
One way plants are able to make physical changes rapidly in response to stress is to modify the epigenome. What the heck is an epigenome?
CAUTION: super sciencey stuff ahead
The epigenome means “on top of” the genome, and epigenetics refers to changes to the surface of the genome, without altering DNA sequences. One of the mechanisms of action for epigenetic changes occurs through the attachment or removal of methyl groups to cytosine and guanine linked by a phosphate bond in the DNA sequence.This can lead to changes in expression levels of various genes by exposing or suppressing genes. Stress is known to change methylation on the epigenome, but this has not yet been evaluated in clonal organisms, and the level of stress response is unknown. I propose to conduct controlled experiments to explore epigenetic modification of the epigenome in both the mother plant from which the clones were taken, and also the clones themselves.
So guess what I'm doing? (PS: no comments about my form- I are science, I are not grower)
Mothers from seed: BaOX and Otto II from Centennial Seeds
Mothers and their first round of clones
Do you have roots yet? (photo credit: Woody Myers)
Clones of clones
Tissue samples from clones (TOC= top of clones)
DNA extractions: 300 at a time should be good.
Those glowing bands are DNA: The extractions were a success!
PCR with extra juju. Charms are a must if you want your PCR to work. It's a scientific fact.