next step in a breeding program is to lock down other traits in that same population. Here is the hard part.
When you are working on locking down a trait you must not eliminate other desirable traits from the population. It is also possible to accidentally lock down an unwanted trait or eliminate desired traits if you are not careful. If this happens then you’ll have to work harder to explore genotypes through multiple cross tests and lock down the desired traits. Eventually, through careful selection and record keeping you’ll end up with a plant that breeds true for all of the features that you want. In essence, you will have your own genetic map of your cannabis plants.
Successful breeders don’t try to map everything at once. Instead, they concentrate on the main phenotypes that will make their plant unique and of a high quality. Once they have locked down four or five traits they can move on. True breeding strains are created slowly, in stages. Well-known true breeding strains like Skunk#1 and Afghani#1 took as long as 20 years to develop. If anyone states that they developed a true breeding strain in 1 or 2 years you can be sure that the genetics they started with were true breeding, homozygous, in the first place.
Eventually you will have your Silver Kush strain but only with the four genotypes that you wanted to keep. You may still have a variety of non-uniform plants in the group. Some may have purple stems, while others may have green stems. Some may be very potent and others not so potent. By constantly selecting for desired traits you could theoretically manipulate the strain into a true breeding strain for every phenotype. However, it is extremely unlikely that anyone will ever create a 100% true breeding strain for every single phenotype. Such a strain would be called a perfect IBL. If you’re able to lock down 90% of the plant’s phenotypes in a population then you can claim that your plant is an IBL.
The core idea behind the true breeding technique is to find what is known as a donor plant. A donor plant is one that contains a true breeding trait (homozygous, preferably dominant for that trait). The more locked down traits are homozygous dominant the better your chances of developing an IBL, which does not mean that the line of genetics will be true breeding for every trait, but rather that the strain is very uniform in growth for a high percentage of phenotypes.
Some additional advanced breeding techniques that will help you to reduce or promote a trait in a population are discussed below. Using these techniques may not create a plant that is true breeding for the selected traits, but it will certainly help to make the population more uniform for that trait.
ADVANCED BREEDING TECHNIQUES
Simple Backcrossing
Our first cross between the Master Kush plant and the Silver Haze is known as the F1 hybrid cross. Let’s pretend that both traits are homozygous for leaf color: the Silver Haze is pale green and the Master Kush is dark green. Which is SS or ss? We won’t know until we see the offspring.
F1 Hybrid Cross
s
s
S
Ss
Ss
S
Ss
Ss
This F1 cross will result in hybrid seeds. Since S is dominant over s, we’ll know which color is more dominant and from which parent it came from. In this example, the overall results are pale green. Thus, the pale-green allele is dominant over the dark-green.
S = Silver Haze pale-green leaf trait is dominant
s = Master Kush dark-green leaf trait is recessive
We also know that because no variations occurred in the population, both parents were homozygous for that trait. However, all the offspring are heterozygous. Here is where we can take a shortcut in manipulating the gene pool for that population. By cloning the parent plant SS, we can use this clone in our cross with the Ss offspring. This is known as a backcross. Obviously, if our parent is female then we’ll have to use males from the Ss selection in our backcross, and vice versa.
Now
When you are working on locking down a trait you must not eliminate other desirable traits from the population. It is also possible to accidentally lock down an unwanted trait or eliminate desired traits if you are not careful. If this happens then you’ll have to work harder to explore genotypes through multiple cross tests and lock down the desired traits. Eventually, through careful selection and record keeping you’ll end up with a plant that breeds true for all of the features that you want. In essence, you will have your own genetic map of your cannabis plants.
Successful breeders don’t try to map everything at once. Instead, they concentrate on the main phenotypes that will make their plant unique and of a high quality. Once they have locked down four or five traits they can move on. True breeding strains are created slowly, in stages. Well-known true breeding strains like Skunk#1 and Afghani#1 took as long as 20 years to develop. If anyone states that they developed a true breeding strain in 1 or 2 years you can be sure that the genetics they started with were true breeding, homozygous, in the first place.
Eventually you will have your Silver Kush strain but only with the four genotypes that you wanted to keep. You may still have a variety of non-uniform plants in the group. Some may have purple stems, while others may have green stems. Some may be very potent and others not so potent. By constantly selecting for desired traits you could theoretically manipulate the strain into a true breeding strain for every phenotype. However, it is extremely unlikely that anyone will ever create a 100% true breeding strain for every single phenotype. Such a strain would be called a perfect IBL. If you’re able to lock down 90% of the plant’s phenotypes in a population then you can claim that your plant is an IBL.
The core idea behind the true breeding technique is to find what is known as a donor plant. A donor plant is one that contains a true breeding trait (homozygous, preferably dominant for that trait). The more locked down traits are homozygous dominant the better your chances of developing an IBL, which does not mean that the line of genetics will be true breeding for every trait, but rather that the strain is very uniform in growth for a high percentage of phenotypes.
Some additional advanced breeding techniques that will help you to reduce or promote a trait in a population are discussed below. Using these techniques may not create a plant that is true breeding for the selected traits, but it will certainly help to make the population more uniform for that trait.
ADVANCED BREEDING TECHNIQUES
Simple Backcrossing
Our first cross between the Master Kush plant and the Silver Haze is known as the F1 hybrid cross. Let’s pretend that both traits are homozygous for leaf color: the Silver Haze is pale green and the Master Kush is dark green. Which is SS or ss? We won’t know until we see the offspring.
F1 Hybrid Cross
s
s
S
Ss
Ss
S
Ss
Ss
This F1 cross will result in hybrid seeds. Since S is dominant over s, we’ll know which color is more dominant and from which parent it came from. In this example, the overall results are pale green. Thus, the pale-green allele is dominant over the dark-green.
S = Silver Haze pale-green leaf trait is dominant
s = Master Kush dark-green leaf trait is recessive
We also know that because no variations occurred in the population, both parents were homozygous for that trait. However, all the offspring are heterozygous. Here is where we can take a shortcut in manipulating the gene pool for that population. By cloning the parent plant SS, we can use this clone in our cross with the Ss offspring. This is known as a backcross. Obviously, if our parent is female then we’ll have to use males from the Ss selection in our backcross, and vice versa.
Now
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