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Thread: F1,F2,F3? help me understand these

  1. #1

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    Default Answered: F1,F2,F3? help me understand these

    hi people,

    Whats the difference between F1, F2, F3 seeds. I see it in the blurb sometimes when buying seeds but never understand what they are.

  2. "Heterzygous - a condition when two genes for a trait are not the same on each member of a pair of
    homologous chromosomes; individuals heterozygous for a trait are indicated by an "Aa" or "aA" notation
    and are not true breeding for that trait.(Clarke)

    Homozygous - the condition existing when the genes for a trait are the same on both chromosomes of a
    homologous pair; individuals homozygous for a trait are indicated by "AA" or "aa" and are true breeding
    for that trait. (Clarke)

    - Now the heterozygous and homozygous terms can be applied to one trait or a group of traits within an
    individual or a group of individuals. Depending on your point of reference, an individual or group can be
    considered both homozygous or heterozygous. For instance, say you have two individuals that are both
    short (S) and have webbed leaves (W) and have the following genotypes.

    #1 = SSWW
    #2 = SSWw

    They are both homozygous for the short trait but only individual #1 is homozygous for the webbed leaf
    trait. Individual #2 is heterozygous for the webbed leaf trait and would be considered a heterozygous
    individual. As a goup, they would be considered heterozygous in general by some and homozygous by
    others. It would depend on your point of reference and the overall importance you place on the webbed
    leaf trait. Most would consider it to be heterozygous.

    For example, the blueberry cannabis strain is considered a true breeding homozygous seed line because
    as a whole the many offspring have a similar look and produce a similar product. However there are
    often subtle differences between the plants of characters such as stem colour and potency. When taking
    a close look at blueberry, you will find heterozygous traits, but because of the whole overall look, we
    still generally consider them homozygous for the purpose of breeding programs. Using dogs is another
    way to explain this, take a dobie for example, you can tell the difference between dobies, but you can
    tell a dobie from another breed. Ya follow?

    Hybrid - An individual produced by crossing two parents of different genotypes. Clarke says
    that a hybrid is a heterozygous individual resulting from crossing two seperate strains.

    - For the purpose of seedbanks, a hybrid is in general, a cross between any two unrelated seedlines.
    ANY HYBRID IS heterozygous and NOT TRUE BREEDING.

    F1 hybrid - is the first generation of a cross between any two unrelated seedlines in the creation of a
    hybrid. F1 hybrids can be uniform or variable depending on the P1 parent stock used.

    F2 hybrid - is the offspring of a cross between two F1 plants (Clarke). What Clarke and other sources
    don't make clear is do the two F1's need to be from the same parents? By convention they don't. As
    well, german geneticists often describe a backcross of an F1 back to a P1 parent as a F2 cross.

    - OK lets say we take blueberry and cross it with romulan (both relatively true breeding of their unique
    traits) to create the F1 hybrid romberry. Now lets cross the F1 romberry with a NL/Haze F1 hybrid.
    Some could say this is a F1 cross of romberry and NL/Haze. Others could argue that it is a F2 cross
    of two F1 hybrids. Gets confusing doesn't it? Now lets cross this Romberry/NL/Haze(RNH) with a
    Skunk#1/NL#5 F1 hybrid to create RNHSN. Now some would argue that RNHSN is an F1 hybrid
    between RNH and SK/NL seedlines. Others would call it an F2.

    - So what does this mean to the consumer? It means that a seed bank can call a cross whatever it wants
    until the industry adopts some standards. This is what this article will attempt to initiate. Clarke eludes to
    standardising these definitions but never really gets around to it. Fortunately other plant breeding
    communities have (Colangelli, Grossnickle&Russell, Watts, &Wright) and adopting their standards
    makes the most sense and offers the best protection to the seedbank consumer.

    Watts defines an F1 as the heterozygous offspring between two homozygous but unrelated seedlines.
    This makes sense and gives the F1 generation a unique combination of traits; uniform phenotype but not
    true breeding. This is important in the plant breeding world. This means that when a customer buys F1
    seeds that they should expect uniform results. It also means that the breeder's work is protected from
    being duplicated by any other means than using the original P1 (true breeding parents). [There are
    exceptions to this by using techniques such as repeated backcrosses (cubing the clone)]

    F2 crosses are the offspring of crossing two F1 hybrids. This means that they will not be uniform nor
    will they breed true. However, F3, F4, F5, etc will also share these characteristics, so to simplify
    terminology for the seedbanks and seedbank merchants, they can all be classified as F2 seeds in general.

    What does this mean for the preceeding example? Well, the blueberry, romulan, skunk#1, NL#5, and
    haze were all P1 true breeding seedlines or strains (another term that needs clarification). Romberry,
    NL/Haze, and SK/NL were all F1 hybrids. Both the Romberry/NL/Haze and the RNHSN would be F2s.
    Within each group the consumer can know what to expect for the price they are paying.

    Few cannabis seedbanks (if any) and their breeders are following these definitions and are subsequently
    creating confusion within the cannabis seedbuying community. This is a change that needs to happen."


  3. #2

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    Default "copied & pasted"

    Heterzygous - a condition when two genes for a trait are not the same on each member of a pair of
    homologous chromosomes; individuals heterozygous for a trait are indicated by an "Aa" or "aA" notation
    and are not true breeding for that trait.(Clarke)

    Homozygous - the condition existing when the genes for a trait are the same on both chromosomes of a
    homologous pair; individuals homozygous for a trait are indicated by "AA" or "aa" and are true breeding
    for that trait. (Clarke)

    - Now the heterozygous and homozygous terms can be applied to one trait or a group of traits within an
    individual or a group of individuals. Depending on your point of reference, an individual or group can be
    considered both homozygous or heterozygous. For instance, say you have two individuals that are both
    short (S) and have webbed leaves (W) and have the following genotypes.

    #1 = SSWW
    #2 = SSWw

    They are both homozygous for the short trait but only individual #1 is homozygous for the webbed leaf
    trait. Individual #2 is heterozygous for the webbed leaf trait and would be considered a heterozygous
    individual. As a goup, they would be considered heterozygous in general by some and homozygous by
    others. It would depend on your point of reference and the overall importance you place on the webbed
    leaf trait. Most would consider it to be heterozygous.

    For example, the blueberry cannabis strain is considered a true breeding homozygous seed line because
    as a whole the many offspring have a similar look and produce a similar product. However there are
    often subtle differences between the plants of characters such as stem colour and potency. When taking
    a close look at blueberry, you will find heterozygous traits, but because of the whole overall look, we
    still generally consider them homozygous for the purpose of breeding programs. Using dogs is another
    way to explain this, take a dobie for example, you can tell the difference between dobies, but you can
    tell a dobie from another breed. Ya follow?

    Hybrid - An individual produced by crossing two parents of different genotypes. Clarke says
    that a hybrid is a heterozygous individual resulting from crossing two seperate strains.

    - For the purpose of seedbanks, a hybrid is in general, a cross between any two unrelated seedlines.
    ANY HYBRID IS heterozygous and NOT TRUE BREEDING.

    F1 hybrid - is the first generation of a cross between any two unrelated seedlines in the creation of a
    hybrid. F1 hybrids can be uniform or variable depending on the P1 parent stock used.

    F2 hybrid - is the offspring of a cross between two F1 plants (Clarke). What Clarke and other sources
    don't make clear is do the two F1's need to be from the same parents? By convention they don't. As
    well, german geneticists often describe a backcross of an F1 back to a P1 parent as a F2 cross.

    - OK lets say we take blueberry and cross it with romulan (both relatively true breeding of their unique
    traits) to create the F1 hybrid romberry. Now lets cross the F1 romberry with a NL/Haze F1 hybrid.
    Some could say this is a F1 cross of romberry and NL/Haze. Others could argue that it is a F2 cross
    of two F1 hybrids. Gets confusing doesn't it? Now lets cross this Romberry/NL/Haze(RNH) with a
    Skunk#1/NL#5 F1 hybrid to create RNHSN. Now some would argue that RNHSN is an F1 hybrid
    between RNH and SK/NL seedlines. Others would call it an F2.

    - So what does this mean to the consumer? It means that a seed bank can call a cross whatever it wants
    until the industry adopts some standards. This is what this article will attempt to initiate. Clarke eludes to
    standardising these definitions but never really gets around to it. Fortunately other plant breeding
    communities have (Colangelli, Grossnickle&Russell, Watts, &Wright) and adopting their standards
    makes the most sense and offers the best protection to the seedbank consumer.

    Watts defines an F1 as the heterozygous offspring between two homozygous but unrelated seedlines.
    This makes sense and gives the F1 generation a unique combination of traits; uniform phenotype but not
    true breeding. This is important in the plant breeding world. This means that when a customer buys F1
    seeds that they should expect uniform results. It also means that the breeder's work is protected from
    being duplicated by any other means than using the original P1 (true breeding parents). [There are
    exceptions to this by using techniques such as repeated backcrosses (cubing the clone)]

    F2 crosses are the offspring of crossing two F1 hybrids. This means that they will not be uniform nor
    will they breed true. However, F3, F4, F5, etc will also share these characteristics, so to simplify
    terminology for the seedbanks and seedbank merchants, they can all be classified as F2 seeds in general.

    What does this mean for the preceeding example? Well, the blueberry, romulan, skunk#1, NL#5, and
    haze were all P1 true breeding seedlines or strains (another term that needs clarification). Romberry,
    NL/Haze, and SK/NL were all F1 hybrids. Both the Romberry/NL/Haze and the RNHSN would be F2s.
    Within each group the consumer can know what to expect for the price they are paying.

    Few cannabis seedbanks (if any) and their breeders are following these definitions and are subsequently
    creating confusion within the cannabis seedbuying community. This is a change that needs to happen.

  4. #3

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    Default

    Basically the higher the number, the more stable the strain.

    Get two plants and cross them = F1. This is a stable strain - all plants from these seeds will look the same.
    Breed two F1s and get F2. With F2s any trait can show. These are the most unstable strain.
    Now get two matching F2s and breed those and you get F3s with the traits you want = selective breeding.

    If you went to say F10 you would end up with a very stable plant with the exact traits you wanted.

    Hope that makes sense...then again I also hope I'm right lmao.

  5. #4

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    Default

    I could have this seriously wrong but this is what I understood.

    Basically, an F1 is when two pure strains are bred together. The genes in the plant are usually in pairs (diploid) so a plant with AA as a gene pair is crossed with a plant with a gene pair aa. Each gene pair carries the genes from each parent so each F1 gen is Aa. The A is dominant over the a so it shows this as the same phenotype as the AA parent. The F1 will often be a stronger plant than either parent as new genes give them more vigour. The F1 plants grown from seed will show the same characteristics (it's phenotype).
    The off spring of these can be bred together and so each Aa gene is paired with Aa. When each Aa gene pair is crossed with another Aa gene pair (i.e. 2 F1 parents) this gives the following offspring:
    A a
    A AA Aa

    a Aa aa
    This means that there are three new gene pairs in the offspring (the F2): AA Aa and aa. They will show different characteristics and so the F2 generation will produce different plants from the same crop of seeds. If you want the plants with the aa gene pair only one in four of the offspring will be this. The other three will show the other phenotype. F3 and F4 are the breeding from these seeds and this breeding reduces the variation by crossing each desirable plant with another, often called stabilising.

    In industry (non canna) F1's are used to produce a consistent crop of bedding/tomatoes/etc where all the plants are the same. If you then try to collect these seeds the results the next year will not be the same so you have to go out and buy new seeds every year.

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