A cannabis seed lies dormant, waiting for the necessary requirements to start a new life. Radicle will become root, cotyledons will become the first leaves to appear, and the shoot apex nestled between the cotyledons will become the very top of the growing plant.

Waiting to fuel to process is the desiccated endosperm, full of carbohydrate, protein, and fats, ready to fuel explosive growth. The tough outer-coat of the seed protects it until the conditions are ideal.

The first step is imbibition, whereby water will be absorbed by the dry seed. When the seed has absorbed a sufficient amount of water enzymes will re-hydrate and become active. The active enzymes will begin to break down food stored in the endosperm, catalyzing the development of the embryo.

This type of metabolism is called aerobic respiration. Oxygen is required in this metabolic process. As the seed embryo consumes the food stored in the endosperm, it will take in oxygen and release carbon dioxide. Without access to oxygen, the seed will lack the necessary inputs to create energy and will fail to thrive.

The root emerges and seeks nutrients. As the stored food is used up the root seek out additional nutrients from the surrounding medium, developing the rhizosphere.

As the cotyledons begin to emerge and push the seed coat off, the apex opens up and the first true leaves emerge. Photosynthesis now provides the energy for the growing plants.

To sprout cannabis seeds follow these steps:

1. Soak in deionized water for 24-48 hours.
2. Place in a damp paper towel for 24-48 hours.
3. Transplant to a moist medium, being careful to keep the medium wet but not flooded.

As the seedlings emerge they will need the following to thrive:

• A light nutrient solution (70%) or ‘starting-strength’ grow media
• Low-intensity lighting (T5 or shaded sun)
• Mild temperatures (65-72F)
• Consistent moisture (relative humidity)
• A slight breeze (air movement)

Determining when to move a seedling from water to paper towel to medium is a challenge for new growers.
When a seed shows a tap root it is ready to move to a paper towel.
When some of the seeds begin to show their leaves it is time to move to medium.

Maintaining ideal conditions becomes the next challenge.

The light source can be too intense and burn seedlings – it can be too far away and seedlings can stretch. The medium can be too dry causing the seedlings to wither – the medium can soak and cause the roots to drown and rot without oxygen. Nutrients can be too strong or too weak. The temperatures can be too hot or too cold. If air circulation is lacking, the seedlings will choke off their own respiration cycles.

Building and maintaining a proper environment consistently is a challenge but it will give your seedlings the best possible start.

(of language) used in ordinary or familiar conversation; not formal or literary.

A language adapts to the needs of its users. We all experience language differently as we interact with those around us. Sometimes a subset of people start using a new word or words differently and it can become part of their identity. Genetic Drift has been appropriated to describe a phenomenon where a clone breaks down over time, becoming less healthy, less potent, and lower yielding. The characteristics of the clone drifts from what it once was to something reduced. Now only in memory can we remember its former glory, a wistful longing.

Genetic Drift also has another meaning, one recognized as the scientific definition:

The variation in the relative frequency of different genotypes in a small population, owning the chance disappearance of a particular genes as individuals die or do not reproduce.

We normally think of survival of the fittest as the rule of thumb. This is the concept that a plant has characteristics that make it better able to pass on its genes to the next population so it produces offspring at a higher frequency. But raw chance can also be a factor, especially with small populations. For example, let’s say we have a bag of 100 seeds and 50% are purple phenos. Now the dog eats 75 seeds. Randomly, since the purple seeds do not taste any different, the dog eats most of the purple pheno seeds. When we pop the remaining 25 seeds 90% are green and 10% are purple. The green phenos were not any better they just got lucky and now they make up more of the population.

This puts the word Genetic Drift in a bit of a pickle. To one group it has one meaning and to another, it means something different. But a clone deteriorating over time is an observable phenomenon that is generally recognized to be true.

How is this occurrence described in the scientific community?

It is described as the modification of gene expression rather than a change in the genetic code itself. Epigenetics studies how a plant changes its gene expression in response to stimuli such as cold, predation, and drought. The plant will express different genes in response to stimuli. Now the question remains, once a plant has experienced insect predation, drought, or any stress in general, can it be returned to its former state before the stress changed it?

This article was written by valkyrie_onhigh.

the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself.

AGCT, adenine, guanine, cytosine, thymine, are the nucleotides that make up the four-letter alphabet of DNA. DNA is transcribed into RNA. From RNA, proteins are translated and the building blocks for life are created. A single cell contains all of the information to build an entire organism including leaves, stems, flowers, and roots. Cells differentiate into distinct types because particular genes are active in distinct cell types. Signaling causes this specialization to occur as epigenetic tags activate and silence the expression of specific genes.

The physical structure of the DNA determines if a gene can be expressed. If the DNA is tightly wrapped around histones and covered in chemical tags then the DNA will be unreadable. Signals from the outside world can cause the removal of the epigenetic tags allowing the DNA to relax and become readable.

Plants are exposed to stressors such as heat, predation, drought, cold, humidity, excess light, and infection. In each of these cases, these stressors trigger a cascade of signals that results in a response.

Scientists recently studied the chemical tags in European holly to determine if deer herbivory changed the genetic structure and genetic expression. The structure of the leaf can present in two forms, prickly or smooth. The scientists saw a decrease in chemical tags among the prickly leave phenotypes and also saw an increase in the prickly leave phenotypes when the holly was being munched on.

Increasingly interesting are the studies looking at how these epigenetic changes are passed through generations. Scientists studied this phenomenon in Arabidopsis by infecting the parent with a bacterial infection. The parent mustered defense mechanisms to combat the infection.

The response was found in the second generation even without the bacterial infection present to stimulate a response.

How is this related to cannabis?

We keep mothers as genetic reservoirs. Sometimes these mothers encounter stressors and when we flower out the clones they begin to show signs of degradation. This could be caused by the change in genetic expression as the plant responds to stress.

One of the most deleterious stress responses is the hermaphrodite trait in female plants. Undiscovered hermies can pollinate a flowering room leading to lower grade flowers considered undesirable by most smokers. Sometimes smokers flower out this bag seed and see that the progeny also presents with the hermaphrodite trait.

A hypothesis could be formed that the stress induced hermaphrodite response is primed in the next generation.

Some cannabis breeders choose not to breed with hermaphrodite progeny or create feminized seeds due to both the anecdotal evidence that this characteristic is expressed in subsequent generations and the peer-reviewed studies on other plant species pointing to the generational expression of stress responses. However, there is hope that breeding through multiple generational lines can erase the response and the genes coding for the stress response will become tightly wrapped around histones with tags yet again, preventing expression until they are exposed to stress.

This article was written by valkyrie_onhigh.

Sources:
http://onlinelibrary.wiley.com/doi/10.1111/boj.12007/abstract
http://www.plantphysiol.org/content/158/2/545.short
http://learn.genetics.utah.edu/content/epigenetics/