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I posted this here from CC magazine for Rosebud and others that would like to read the whole article from DJ Short, creator of the Blue line among others.
url: hMPp://www.cannabisculture.com/articles/2788.html
By DJ Short - Friday, March 7 2003
FOLLOW: BREEDING GENETICS GROWING INDOOR
Perhaps the most important aspect to consider in the breeding of fine quality cannabis is that of selection. Selective breeding is where all of today's varieties evolved from.
In the past, this chore was made easier by the fact that most of the commercially available herb was seeded and imported from outdoor plantations, usually near-equatorial in origin. These "land-race" Sativa varieties were the building blocks of the burgeoning domestic productions of the times.
The Indica (Afghan, Kush, Skunk, etc.) genetics were specially imported by West Coast interests and available to the general public around 1978. It was shortly after this time that the variance of domestic cannabis increased exponentially, as people began experimenting with crossing these two different types of pot.
Beginning breeding
The typical way to begin a breeding program is to carefully select P1 parents of pure Sativa and pure Indica, crossing them to produce an f1 hybrid that is uniform in its phenotypic growth patterns. The next step is the crossing of the f1 type with itself, which produces a very wide variation witnessed in the f2 growth patterns and expressions.
It is in this f2 second-generational cross and beyond that the art of selection really comes into play. There are a number of factors to consider at this point, such as what the male and female will each contribute; and most of all, what will the overall quality of the finished product be like?
Defining a goal and constructing a plan to accomplish it is called "top-down" programming, and this "top-down" approach applies well to cannabis breeding. It helps considerably to have a specific goal in mind when attempting to selectively breed a variety of ganja. This simple fact I cannot emphasize enough.
One must at least have an idea of what one is aiming for before beginning. For me this has little to do with plant structure and much to do with the quality of the finished product, no matter what form it is in. Having an experienced and educated palate (both mentally aesthetic and physically discernable) is key in the art of breeding fine quality cannabis.
The "goal" at the center of most of my breeding targets would be to replicate, as near as possible, the experiences produced by the great land-race varieties of old: Highland Oaxacan or Thai, Santa Marta or Acapulco Gold, Guerrero Green, Panama Red or Hawaiian Sativa? or the hash from regions such as Lebanon, Afghanistan or Nepal.
The indoor grow environment is too generic to fully replicate the great old legends. Therefore, it was necessary to settle for the next best thing: happy Sativa/Indica crosses that would perform well indoors. (It is interesting to note here that most of the fine land-race Sativa were hermaphroditic, though sometimes only minimally.)
Selection process
Obviously, you seek the parents that will produce the desired progeny. Paradoxically, this process requires selecting the best after they've been harvested. The solution is to keep samples from each plant of a test crop. This can be done via rooted clones from earlier cuttings, or re-greened mothers and fathers kept in a vegetative state and a high-nitrogen diet. Once you have chosen among the harvested plants, you can use the rooted cuttings for future consideration and possible breeding.
Pollen may also be gathered and immediately stored via vacuum sealing and deep-freezing. It is crucial to vacuum seal and freeze pollen immediately after it is collected and to use stored pollen immediately after it thaws. Dry seeds also store well over indefinite periods of time in an undisturbed deep-freeze, with some desiccant.
This process of post-harvest selection works fine for selecting desired female plants. But what about males? What is the best and most simple way to select males for breeding? Due to the fact that it is the female plants that we are ultimately familiar with, selecting males is a bit more involved.
The process is basically the same as it is with female plants, except with males the numbers are first limited down via a process of elimination, and selections made by comparing the remainder. Selecting males also takes a little more time initially as the quality of the male is not fully determined until after the seeds it produces are grown out and tested. As one becomes more familiar with a particular strain, the specific characteristics of the desirable males become apparent.
Ideally, the more seeds one starts with the better. This is, after all, a numbers game. I will assume that any basic breeding project starts with at least 20 different plants, from 20 viable seeds of high quality, professionally stabilized varieties. This would give a minimum of 10 male and 10 female plants hopefully sexed by two weeks into a flowering light cycle (short day/long night).
Once sexed, the process of elimination may begin. All of the females are kept and regularly examined to prevent unwanted hermaphroditism. Unwanted males and all hermaphrodites must be eliminated before they begin to shed pollen ? usually by the third week in the flowering cycle. The female plants need to be checked for hermaphroditism until harvest.
(A quick word on "backward" hermaphrodites ? declared males that eventually sport female flowers ? as opposed to the usual female-to-male hermaphrodites. These are semi-rare occurrences, usually sterile but sometimes viable, that I have found at times to be valuable in their genetic contributions. Some of the most resinous and desirable males I have encountered exhibited this trait. This trait almost seems to guarantee against unwanted hermaphroditism in subsequent generations as it also increases the female to male ratio in its progeny.)
Recessivecombination
A word needs to be said about the not-too-common probabilities of what I generally refer to as a recessive combination phenomenon. Sometimes, though not often, two parents that appear to express a common desirable trait ? let's say a sweet/fruity bouquet ? are crossed and the progeny do not express the desirable trait.
This usually means that one or both parents possessed some sort of recessive alleles in their genotype for this characteristic. But it could also mean that the progeny had a different environment that the parents.
If environment can be ruled out then it is likely that some sort of a genetic recessive combination is the cause. If none of the progeny express the desired characteristic one may want to cross the progeny with itself and see what the outcome is.
If a common "Punnet ratio" such as 25% of a progeny express the desirable trait, then the trait is more than likely recessive and the trait may be stabilized via crossing any two of the 25% (or whatever common ratio) that show the desired trait with each other. This process is time consuming and is generally followed only if no other alternatives exist.
url: hMPp://www.cannabisculture.com/articles/2788.html
The art of selection and breeding fine quality cannabis
How to create amazing new strains with a discerning palate, careful selection and some hard work.
By DJ Short - Friday, March 7 2003
FOLLOW: BREEDING GENETICS GROWING INDOOR
Perhaps the most important aspect to consider in the breeding of fine quality cannabis is that of selection. Selective breeding is where all of today's varieties evolved from.
In the past, this chore was made easier by the fact that most of the commercially available herb was seeded and imported from outdoor plantations, usually near-equatorial in origin. These "land-race" Sativa varieties were the building blocks of the burgeoning domestic productions of the times.
The Indica (Afghan, Kush, Skunk, etc.) genetics were specially imported by West Coast interests and available to the general public around 1978. It was shortly after this time that the variance of domestic cannabis increased exponentially, as people began experimenting with crossing these two different types of pot.
Beginning breeding
The typical way to begin a breeding program is to carefully select P1 parents of pure Sativa and pure Indica, crossing them to produce an f1 hybrid that is uniform in its phenotypic growth patterns. The next step is the crossing of the f1 type with itself, which produces a very wide variation witnessed in the f2 growth patterns and expressions.
It is in this f2 second-generational cross and beyond that the art of selection really comes into play. There are a number of factors to consider at this point, such as what the male and female will each contribute; and most of all, what will the overall quality of the finished product be like?
Defining a goal and constructing a plan to accomplish it is called "top-down" programming, and this "top-down" approach applies well to cannabis breeding. It helps considerably to have a specific goal in mind when attempting to selectively breed a variety of ganja. This simple fact I cannot emphasize enough.
One must at least have an idea of what one is aiming for before beginning. For me this has little to do with plant structure and much to do with the quality of the finished product, no matter what form it is in. Having an experienced and educated palate (both mentally aesthetic and physically discernable) is key in the art of breeding fine quality cannabis.
The "goal" at the center of most of my breeding targets would be to replicate, as near as possible, the experiences produced by the great land-race varieties of old: Highland Oaxacan or Thai, Santa Marta or Acapulco Gold, Guerrero Green, Panama Red or Hawaiian Sativa? or the hash from regions such as Lebanon, Afghanistan or Nepal.
The indoor grow environment is too generic to fully replicate the great old legends. Therefore, it was necessary to settle for the next best thing: happy Sativa/Indica crosses that would perform well indoors. (It is interesting to note here that most of the fine land-race Sativa were hermaphroditic, though sometimes only minimally.)
Selection process
Obviously, you seek the parents that will produce the desired progeny. Paradoxically, this process requires selecting the best after they've been harvested. The solution is to keep samples from each plant of a test crop. This can be done via rooted clones from earlier cuttings, or re-greened mothers and fathers kept in a vegetative state and a high-nitrogen diet. Once you have chosen among the harvested plants, you can use the rooted cuttings for future consideration and possible breeding.
Pollen may also be gathered and immediately stored via vacuum sealing and deep-freezing. It is crucial to vacuum seal and freeze pollen immediately after it is collected and to use stored pollen immediately after it thaws. Dry seeds also store well over indefinite periods of time in an undisturbed deep-freeze, with some desiccant.
This process of post-harvest selection works fine for selecting desired female plants. But what about males? What is the best and most simple way to select males for breeding? Due to the fact that it is the female plants that we are ultimately familiar with, selecting males is a bit more involved.
The process is basically the same as it is with female plants, except with males the numbers are first limited down via a process of elimination, and selections made by comparing the remainder. Selecting males also takes a little more time initially as the quality of the male is not fully determined until after the seeds it produces are grown out and tested. As one becomes more familiar with a particular strain, the specific characteristics of the desirable males become apparent.
Ideally, the more seeds one starts with the better. This is, after all, a numbers game. I will assume that any basic breeding project starts with at least 20 different plants, from 20 viable seeds of high quality, professionally stabilized varieties. This would give a minimum of 10 male and 10 female plants hopefully sexed by two weeks into a flowering light cycle (short day/long night).
Once sexed, the process of elimination may begin. All of the females are kept and regularly examined to prevent unwanted hermaphroditism. Unwanted males and all hermaphrodites must be eliminated before they begin to shed pollen ? usually by the third week in the flowering cycle. The female plants need to be checked for hermaphroditism until harvest.
(A quick word on "backward" hermaphrodites ? declared males that eventually sport female flowers ? as opposed to the usual female-to-male hermaphrodites. These are semi-rare occurrences, usually sterile but sometimes viable, that I have found at times to be valuable in their genetic contributions. Some of the most resinous and desirable males I have encountered exhibited this trait. This trait almost seems to guarantee against unwanted hermaphroditism in subsequent generations as it also increases the female to male ratio in its progeny.)
Recessivecombination
A word needs to be said about the not-too-common probabilities of what I generally refer to as a recessive combination phenomenon. Sometimes, though not often, two parents that appear to express a common desirable trait ? let's say a sweet/fruity bouquet ? are crossed and the progeny do not express the desirable trait.
This usually means that one or both parents possessed some sort of recessive alleles in their genotype for this characteristic. But it could also mean that the progeny had a different environment that the parents.
If environment can be ruled out then it is likely that some sort of a genetic recessive combination is the cause. If none of the progeny express the desired characteristic one may want to cross the progeny with itself and see what the outcome is.
If a common "Punnet ratio" such as 25% of a progeny express the desirable trait, then the trait is more than likely recessive and the trait may be stabilized via crossing any two of the 25% (or whatever common ratio) that show the desired trait with each other. This process is time consuming and is generally followed only if no other alternatives exist.