Seeds and Strains by Mel Thomas

Cannabis breeder’s will start with homozygous, true breeding strains, that show little variation in traits and characteristic such as size, yield, potency and flavour, these traits and characteristics are called phenotypes. When breeders cross these true breeding strains with other true breeders they produce what are known as heterozygous or hybrid strains. Hybrids will display something called, ‘hybrid vigour’ (heterosis), which is the term used to describe stronger, more vigorous plants created by a fresh combination of different genes.

Homozygous means a true breeding strain

Heterozygous means a hybrid with variation in plants

Phenotypes describes the characteristics of different strains

 

Not all crosses are an improvement on the parents; some crosses will give you random results so breeding can become something of a gamble. A hybrid plant is labelled F1, for a first cross, F2 for a second then F3 and so on. The phenotypes in these hybrids will vary more than in the homozygous parents, and as you progress down toward F3 and F4 the variations in your crop are more noticeable. Generations after F1 are acceptable to use but don’t have the same vigour or consistent characteristics as F1 hybrids.

There are three distinct cannabis drug varieties bred specifically for their psychoactive compounds, these are:

Cannabis sativa (C.sativa)

These varieties originate from equatorial regions and can reach heights in excess of 15 ft (4.5m). They produce thin, spiky leaves and massive colas that are not very dense. Pure C.sativa strains are not used for indoor cultivation due to their size, a finished C.sativa can take up 4 to 8 times the space of a compact C.indica variety.

However, there are many hybrids available such as the original Skunk#1 (75% sativa, 25% indica) that are ideal for indoor cultivation and the harvested buds have a high calyx (flower) to leaf ratio meaning there are less leaves to trim from the finished buds. Skunk#1 was developed in the 1970 s and has since been incorporated into many modern strains.

If you wish to experiment with pure C.sativas then try a variety such as Durban Poison that originates from South Africa and hasn’t been hybridised. It remains 100% sativa and produces large resinous flowers similar to Thai, but these plants will need to be pruned back hard to keep them small. Haze is another pure variety also developed in the 1970 s and widely regarded as one of the most potent cannabis strains available. However, it is difficult to grow, has a longer than average flowering period and unlike the hybrids that are available it only produces moderate yields.

Cannabis indica (C.indica)

This variety originated from the mountainous regions of Central Asia. Local strains were collected from Kashmir, Pakistan, Northern India and Nepal during the early 1960 s and these native plants became the gene pool for many of today s varieties. They are characteristically stocky and hardy plants that produce broad, maple like leaves and rarely reach heights in excess of 2m (7ft) outdoors, producing heavy, tight flowers that are high in psychoactive content.

Cannabis indica plants are ideal for indoor cultivation and pure strains can produce heavy yields, although they are temperamental for the first time grower. Hindu Kush is a good starter plant for anyone who wants to grow pure Indica plants. Afghani is another pure variety imported from Afghanistan that produces heavy resinous buds that will turn purple at harvest time and have a high calyx to leaf ratio. G13 is another pure Indica, reputedly developed by a US govt trial in Mississippi and it contains very high levels of THC,.These are all recommended varieties for indoor cultivation but some can become leafy and require regular defoliating in smaller set-ups.

Cannabis ruderalis (C.ruderalis)

This is a debated third variety of cannabis found in Russia, Poland, and other eastern European countries. Schultes classified cannabis as having three species: Sativa, Indica, and Ruderalis based on the formation of the seed pods.There is still some debate as to whether there is justification for this third category. Some features of Cannabis ruderalis are large seeds, weedy plants around 150cm (5ft) tall and a lower level of THC than C.sativas or C.indicas.

However it is a hardy plant that flowers early, in most cases regardless of the photoperiod. The flowers tend to be sparse and don t produce the same yields as other varieties; but it is a reasonable plant to use for compact indoor cultivation and has been successfully crossed with the other two varieties to produce potent, early flowering (autoflower) plants.

There are so many strains and varieties available now that it is not possible to recommend one particular seed strain. Your choice of plant depends very much on your circumstances. If you are growing recreationally then a priority would be flavour and psychoactive effect, other growers are more focussed on yield and flowering times, however, medical cannabis patients have more specific requirements. Most cannabis strains available today have been selectively bred for high THC content and cannabidiol (CBD) which is the non psychoactive cannabinoid contained in the plant, has effectively been bred out. This is primarily due to CBD actually reducing the intensity of THC when ingested.

There has been some ground breaking research carried out by Doctor Manuel Guzman of Madrid University in Spain that has shown how important CBD is when treating cancer patients. Many breeders are now addressing the issue and there are a few strains available that are very high in CBD – but they are missing the point. When treating aggressive cancers in adults there should be an equal balance of THC and CBD.

Cannabinoids have a symbiotic relationship with each other, they are a complex fusion of approximately 60 different cannabinoids and over 400 active components. These interact with each other so to selectively breed for one specific cannabinoid can cause an imbalance. The reason why we have this THC/CBD imbalance in most strains available today is precisely because plants were selectively bred to favour one particular cannabinoid, in this case principally THC (delta-9-tetrahydrocannabinol).

Now we have breeders trying to stabilize pure CBD plants and a medical research company based in Israeli claims it is the first to develop a strain that contains almost no THC at all. The new cannabis strain took about 3 years to develop through cross-breeding and is called “Avidekel.” The genetics will never be made freely available but I would question why you would want to create a plant that contains none of the medical benefits associated with THC unless you are specifically treating infants and children.

The only validity in producing high CBD, low THC strains is when treating children – they would still benefit from THC, particularly if they have any aggressive forms of cancer, but the treatment needs to take into account the psychoactive side effects of THC on the child. ‘Charlotte’s Web’ is a strain of cannabis named after Charlotte Figi, who controls her epileptic seizures by taking medical cannabis since the age of 5. It is high in CBD content and the extracts are known as Realm Oil or Alepsia. It does not induce the psychoactive effect typically associated with recreational cannabis use and has been used to treat seizures and epilepsy in infants and children.

 

Bud buddies have been lucky enough to obtain a legal research facility in Spain where we make limited amounts of medicinal oils. This Summer we’ll be ending our cancer research and concentrating on paediatric medicinal cannabis. We intend to test and develop our own version of ‘Charlotte’s Web’ specifically to treat children and so far we are up to 14:1 CBD:THC – our target is 27:1.

We test all of our oils independently and have been surprised at some of the test results. Strains claiming to be high in CBD had very little and it later transpired the breeders hadn’t even had the strains laboratory tested. They just made up the CBD content, when we confronted one breeder he claimed it was a rough estimate. However they do not tell you this in their marketing and it is hard to feel good about these companies duping medical users with serious health issues.

Two strains we tested were as the breeders had claimed, ‘Juanita’ by Reggae seeds comes in very high in CBD and correspondingly lower in THC with a laboratory test recording 8.81% CBD content with 6.77% THC. This naturally reflected in the oils we made from each strain. There is little point in making a medicinal cannabis oil for an adult cancer patient from a plant that does not have the full profile of cannabinoids in the correct balance. THC and CBD are of equal importance when fighting cancers.

The other strain we tested and were impressed with was Skunk Haze from the CBD crew. Scott (shantibaba) is the breeder behind the strains and they have spent several years and invested a lot of patience, time and money in testing and selecting the right genetics. We independently tested the oil we made from Skunk Haze at two laboratories, one in Canada and one in Spain. The results were exactly as the CBD crew stated. The resultant oils had an almost perfect 1:1, THC to CBD profile, meaning they have achieved a perfect balance in the plant which is remarkable. Most of Bud Buddies medical oil is made from Skunk Haze.

If you are a medical user you should be cautious about some of the seed companies who actively promote their seeds as high in CBD as they probably aren’t and the important thing to remember is THC is just as essential. Recreational users face different issues, generally unstable genetics are to blame for most problems so ensure your seeds come from good stock as you will be investing a lot of time and money in them. It cant be stressed enough, you need to spend time researching your intended seed choice, be it for medical or recreational use. Google is your friend.

 

By Mel Thomas

Originally published in Weed World Magazine Issue 110