The Cannabis Breeder's Bible (39 page)

In the chloroplast both types work with integral membrane proteins. Due to the chemical arrangement of chlorophyll, and how it is bonded, a special property is created that allows light to be absorbed at the molecular level.

Because a plant is green from chlorophyll does not mean that it absorbs green light!

If you grow a plant under a green bulb the plant will reflect all the green light. Plants are not very interested in green light and that is why they appear green to our eyes because they are
reflecting green light!

Chlorophyll is a magnesium-containing green pigment. When we cure bud we attempt to get rid off chlorophyll. The reason for this is that magnesium burns the throat when hot. This is why poorly cured bud tastes harsh. Some growers choose to flush their plants of nutrients at least a week before harvest. The idea here is that it prevents the plants from creating anymore chlorophyll so that the bud will cure quicker. The side effect of flushing is less bud quantities because the plant is growing in less than optimal conditions before harvest.

Photosynthesis is a process in plants by which carbon dioxide is converted into organic compounds using the energy in light absorbed by the chlorophyll. It is essentially any photochemical synthesis of a chemical compound. CO
₂
generators are very helpful in breeding labs.

The plant photosynthesis flow chart

It is important for us to understand the basics of photosynthesis because it is at the heart of the cannabis plant’s energy system. Green plants have the necessary ability to bio-chemically
make up
complex substances within themselves for themselves. This process is known as photosynthesis.

THE PROCESS OF PHOTOSYNTHESIS

Photosynthesis means
‘combining with light’
. Photosynthesis is a “reactant - product” process which occurs wherever chlorophyll is found in the plant, which is mostly in the leaves. The symbolic equation for photosynthesis is:

6 CO
₂
+ 6 H
₂
O - sunlight & chlorophyll - C
₆
H
₁₂
O
₆
+ 6 O
₂

If there is no light then there is no photosynthesis. At night plants cease photosynthesis. If there is not enough nutrients then chlorophyll will not be produced by the plant and photosynthesis will cease. Temperatures are also important for photosynthesis. If the temperatures go out of the normal range for good cannabis plant health then photosynthesis will slow down or even stop. (See chapter 6 of
The Cannabis Grow Bible
for a more detailed discussion.)

Cannabis does not need a dark period for photosynthesising—although other types of plants do. Cannabis will photosynthesise without problems under the 24/0 or 18/6 vegetative photoperiods.

22

SCIENTIFIC CLASSIFICATION OF CANNABIS

THE CHART BELOW SHOWS THE STANDARD template for cannabis that we find in many botany books, although there may be some deviations from these standards.

KINGDOM: PLANTAE (PLANTS)
SUBKINGDOM: TRACHEOBIONTA – VASCULAR
SUPERDIVISION: SPERMATOPHYTA - SEED
DIVISION: MAGNOLIOPHYTA - FLOWERING
CLASS: MAGNOLIOPSIDA – DICOTYLEDONS
SUBCLASS: HAMAMELIDAE
ORDER: URTICALES
FAMILY: CANNABACEAE (HEMP or sometimes called MORACEAE)
SCIENTIFIC NAME: CANNABIS SATIVA
AUTHORITY: L.

BASICS OF CANNABINOIDS

Cannabis contains more than 400 active chemicals. When these chemicals are vaporized or ignited they can create over 2,000 chemicals. It would be beyond the scope of this book to go into detail about every cannabinoid and the other active chemicals found in cannabis, but in the meantime let’s look at the more commonly known types of cannabinoids and chemicals found in cannabis.

Cannabis contains what is known as “isometric tetrahydrocannabinol.” Cannabis also contains cannabiols and cannabidiols. Most of these types of compounds can produce psychoactive effects.

The cannabis plant is the only known plant on that planet that produces cannabinoids.

Cannabinoids and their respective molecular structures and processes.

THC,
or
delta-9 tetrahydrocannabinol,
is the most important psychoactive chemical in cannabis. It can range in content anywhere between 0.1% and 30%. Unusual samples taken have recorded above 50% but these are more than likely rare variations in a large population. The trait for the 50% THC is undoubtedly unstable in the wild and cannot be attributed to the myth of cannabis being stronger than it used to be that is being put forward today by many politicians and anti-cannabis campaigners. The most potent strains of today are still the same potent strains that were available in the ’70s. Any seed bank that sells potent strains knows that the most potent strains are the Haze strains, which have been around for decades

Cultivated industrial hemp has less than 0.3% THC. Most commercial varieties contain between 9% and 25% THC. As mentioned, wild cannabis plants can go as high as the 50% mark. Good cannabinoid research is still somewhat stifled because of cannabis laws and political bureaucracy.

THE MAJOR CANNABINOID LIST

The cannabis high type is mostly due to delta-9 tetrahydrocannabinol. Delta-9 THC can make up anywhere between 40% and 100% of the psychoactive effect of using cannabis. In some not very potent strains this percentage can go as low as 1%.

Delta-8 tetrahydrocannabinol is another psychoactive ingredient found in cannabis but it comes in much lower doses. It is not thought to be as psychoactive as delta-9 THC.

Normally when chemists, cannabis growers and users refer to THC they are actually referring to both delta-9 THC and delta-8 THC.

CBD is also known as cannabidiol. CBD is found in nearly all psychoactive cannabis strains. It can be present in very small or very large doses. CBD is not thought to be psychoactive on its own, but when mixed with THC it may affect and change the high type depending on the ratio of THC to CBD. CBD contributes to the onset and duration of the high type, although its effects are less substantial than was previously thought.

CBN, or cannabinol, occurs during the breakdown of THC in the curing process. CBN is psychoactive but is considered to be less than 1/5 the strength of THC. CBN may also contribute to the high type depending on its ratios to THC and CBD.

CBC, or cannabichromene, is found in similar low doses to those of CBD and CBN. It may also contribute to high type but is considered to be non-psychoactive. It is believed to be a precursor to THC.

CBG, or cannabigerol, is thought to be non-psychoactive. It is also believed to be a precursor to THC.

THCV, or tetrahydrocannabivarin, is psychoactive but the onset is quick and the duration is short. It is related to THC and is termed a “propyl cannabinoid.” CBD and CBN also have their own propyl cannabinoids. These are CBDV and CBV respectively.

In total there are roughly 66 known cannabinoids from 10 groups and some miscellaneous ones. Each of the 10 groups has some variations. This is still an area of study under investigation so many things that we know about cannabinoids are subject to change.

CANNABINOID RECEPTORS

In the ’60s and ’70s cannabis researchers hypothesized that THC and other cannabinoids work on the brain by targeting exclusive chemical receptors. This hypothesis suggested that cannabinoids belonged to a unique set of molecules that worked across the membranes of cells without disturbing them using a receptor system.

In 1984 it was discovered that synthetic THC inhibited adenylate cyclase (this enzyme occurs in plasma cell membranes) in nerve cells and these chemicals were involved in brain receptor operations. Research continued and in 1988 scientists found that cannabinoid receptors did indeed exist and that these receptors have a direct relationship to cannabinoids. In 1990 the receptors were located by using a “G-protein inhibitory second messenger” technique. A synthetic cannabinoid called CP55940 was found to bind to a receptor called CB1. Scientists hypothesized that the brain must produce its own types of “endogenous cannabinoids” and one was indeed discovered in 1992 and shortly after named “anandamine”. Next scientists found cannabinoid receptors in the immune system. This means that cannabinoids are also immunomodulators. This receptor became known as CB2. Both CB1 and CB2 have developed in the human body as a process of our evolution in symbiosis with the cannabis plant. There is a still a lot of work to be done but these receptors suggest what old hippies have been telling the world for years: cannabis is natural and has many natural properties.

23

FLOWERING CONCEPTS AND CALYX DEVELOPMENT

OVER THE YEARS MANY GROWERS AND BREEDERS have found that force flowering can be somewhat troublesome. The term
force flowering
is used to suggest that the cannabis plant will flower when the 12/12 photoperiod is introduced. This notion is erroneous for a number of reasons and we will endeavor to set the record straight here.

Many growers and breeders have approached me with questions about force flowering. The most common complaint is: “I have switched to 12/12 but have not seen any flowers after 4 weeks. What’s wrong?”

Although this may be a problem with light leakage during the 12/12 photoperiod, in most cases it is not and has to do with the grower’s inability to effectively understand cannabis flowering.
The Cannabis Grow Bible
goes into some depth to explain calyx development, but many growers are still using old flawed concepts when trying to get their plants to flower, so we will expand on this issue a bit here. In the early ’80s and ’90s a string of grow books and magazines told growers that by switching to the 12/12 photoperiod they would induce flowering. This is only partially correct. In order for a plant to respond to the 12/12 photoperiod, it must be sufficiently sexually mature.

A plant’s sexual maturity occurs one to two weeks before initial calyx development appears at the nodes. This initial calyx development is not photoperiod initiated. It is initiated by plant maturity, which has a lot to do with the plant’s hormones and age, and the growing environment.

As a grower you should wait for calyx development to show before initiating the 12/12 photoperiod and even then you can still continue the vegetative cycle for longer by keeping the 24/0 or 16/8 photoperiod, depending on which vegetative photoperiod you choose. Once calyx development has appeared under the vegetative photoperiod, you can trigger flowering by commencing 12/12. It really is that simple. Initial calyx development is by far the best way to gauge maturity and readiness to flower.