Super Silver Haze
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my growing skills are nowhere near the stage of breeding or making femenized seeds but it interests me so here is an article from ICMAG.com on STS Breeding. i cant find the exact thread but when i do ill post it.
enjoy
STS-based reversals and feminized breeding
Terminology for STS breeding:
STS: Silver thiosulfate, a salt compound used in photography. In plants, silver interferes with, or locks out, copper, which is a necessary micronutrient. Making copper unavilable inteferes with ethylene signaling, and reduces expression of traits that are dependent on high levels of ethylene, such as female sex expression and fruit ripening.
Copper: a micronutrient that is necessary to assist certain enzymes in their function. Copper can become toxic at low levels, but a few parts per billion is adequate for plants to express their genetic potential. Because copper is needed at such low levels, it does not take much silver to overwhelm the available copper load and exert its effect.
Ethylene: One of the 5 plant hormones. The levels and ratios of these 5 hormones has a huge impact on the shape, strucutre, aroma, flavor, flowering time, and disease resistance of the plant. Hormones are the chemical messengers that allow DNA to 'talk' to plant tissues and determine the phenotype. Ethylene is primarily involved in flowering, sex determination, fruit ripening, and sensescence (rot). Ethylene is a simple organic molecule, C2 H4, which can also be represented as H2C=CH2.
In cannabis, female plants will produce male flowers if not enough ethylene is present, or if too much gibberellic acid is present. The intersex condition is due to a combination of genetic and environemental factors. Some plants will not turn male under the most extreme stress, and some plants, especially stretchy tropical sativas, will turn with no stress at all. It is my belief that the stress of severe inbreeding, compounded over several generations, is responsible for the majority of hermaphrodites in the drug cannabis gene pool (DCG) today.
Reversal: Treating a female plant with STS in order to collect viable female pollen.
Selfing: Applying female pollen to the female from which it was collected. Example : selecting a particular Willie Nelson cutting, reversing it, and putting the pollen back on another clone of the same plant. Applying that pollen to a different Willie cutting, or to another strain altogether, is not selfing.
F0: The parents selected to start a breeding program. Often referred to as P1 and P2, but this is incorrect.
F1: the first cross between two unrelated parents. The F stands for filial, and refers to the fact that all F1 progeny of the same cross are full brothers and sisters to one another.
S1: The first selfed generation. Selfing an S1 produces an S2, etc. Anecdotal evidence from Sam_Skunkman indicates that continued selfing to the S3 and S4 produces plants so weak that they must be handled very carefully, “like kittens” in his words.
R1's (aka Reversed F1's): When feminized pollen is used to pollinate a different female than the pollen donor. R1's will tend to act like a tradional male x female cross, only all female, while S1's appear to have some different properties that are not yet fully understood. Early reports indicatee that S1's are more consistent than R1's on average, but there are many exceptions, and more research is needed.
BC1: The first backcross generation, ie when an F1 or R1 progeny is crossed back to an F0 parent. Backcrossing can increase the influence of either parent, but continued backcrossing is too much inbreeding, according to both DJ Short and Rezdog, and should be used rarely if at all. One or two backcrosses followed by full-sib mating has beena successful strategy for many breeders, including the creator of Northern Lights.
These terms can be combined for shortand pedigrees. A second backross, followed by three generations of sib-mating, may be represented as a BC2-F3 generation.
Intersex: A condition in which a plant (or animal) displays functional sex organs of both genders. Easier to type than hermaphroditic. My belief is that almost all hermies are genetic females that have weaknesses in their ethylene signaling pathway, which makes them very susceptible to environmental stress.
Stress: Any environmental factor that causes a response by the plant. Stresses can be biotic or abiotic. Biotic stresses include insects, fungi, viruses, predators, and CAMP. Abiotic stresses include drought, poor soil conditions, extreme wind or humidity, or hurricanes or flooding. Both types of stresses can have large effects on phenotype, including induction of intersex phenos.
Hybrid Fertility: The degree to which any two unrelated plants can set seed. For example, crossing an Afghani to a Turk may produce 95% viable seed, whild crossing Durban to Mongolian Indica might only produce 40% viable seed. This is usually a measure of the genetic distance between the parents. The fertility of self-pollinations is unknown but could give the breeder alot of information about the breeding value of the plant in question. A plant that has a desirable phentoype, but is not very self-fertile, is likely very homozygous and will tend to produce consistent offspring.
Micropropagation: Taking very small clones and rooting them in test tubes containing a heat-sterilized nutrient mixture in a agar (gelatin) base. This allows for aseptic (almost sterile) conditioins and precise application of phytochemicals such as STS, auxin, or cytokinin.
enjoy
STS-based reversals and feminized breeding
Terminology for STS breeding:
STS: Silver thiosulfate, a salt compound used in photography. In plants, silver interferes with, or locks out, copper, which is a necessary micronutrient. Making copper unavilable inteferes with ethylene signaling, and reduces expression of traits that are dependent on high levels of ethylene, such as female sex expression and fruit ripening.
Copper: a micronutrient that is necessary to assist certain enzymes in their function. Copper can become toxic at low levels, but a few parts per billion is adequate for plants to express their genetic potential. Because copper is needed at such low levels, it does not take much silver to overwhelm the available copper load and exert its effect.
Ethylene: One of the 5 plant hormones. The levels and ratios of these 5 hormones has a huge impact on the shape, strucutre, aroma, flavor, flowering time, and disease resistance of the plant. Hormones are the chemical messengers that allow DNA to 'talk' to plant tissues and determine the phenotype. Ethylene is primarily involved in flowering, sex determination, fruit ripening, and sensescence (rot). Ethylene is a simple organic molecule, C2 H4, which can also be represented as H2C=CH2.
In cannabis, female plants will produce male flowers if not enough ethylene is present, or if too much gibberellic acid is present. The intersex condition is due to a combination of genetic and environemental factors. Some plants will not turn male under the most extreme stress, and some plants, especially stretchy tropical sativas, will turn with no stress at all. It is my belief that the stress of severe inbreeding, compounded over several generations, is responsible for the majority of hermaphrodites in the drug cannabis gene pool (DCG) today.
Reversal: Treating a female plant with STS in order to collect viable female pollen.
Selfing: Applying female pollen to the female from which it was collected. Example : selecting a particular Willie Nelson cutting, reversing it, and putting the pollen back on another clone of the same plant. Applying that pollen to a different Willie cutting, or to another strain altogether, is not selfing.
F0: The parents selected to start a breeding program. Often referred to as P1 and P2, but this is incorrect.
F1: the first cross between two unrelated parents. The F stands for filial, and refers to the fact that all F1 progeny of the same cross are full brothers and sisters to one another.
S1: The first selfed generation. Selfing an S1 produces an S2, etc. Anecdotal evidence from Sam_Skunkman indicates that continued selfing to the S3 and S4 produces plants so weak that they must be handled very carefully, “like kittens” in his words.
R1's (aka Reversed F1's): When feminized pollen is used to pollinate a different female than the pollen donor. R1's will tend to act like a tradional male x female cross, only all female, while S1's appear to have some different properties that are not yet fully understood. Early reports indicatee that S1's are more consistent than R1's on average, but there are many exceptions, and more research is needed.
BC1: The first backcross generation, ie when an F1 or R1 progeny is crossed back to an F0 parent. Backcrossing can increase the influence of either parent, but continued backcrossing is too much inbreeding, according to both DJ Short and Rezdog, and should be used rarely if at all. One or two backcrosses followed by full-sib mating has beena successful strategy for many breeders, including the creator of Northern Lights.
These terms can be combined for shortand pedigrees. A second backross, followed by three generations of sib-mating, may be represented as a BC2-F3 generation.
Intersex: A condition in which a plant (or animal) displays functional sex organs of both genders. Easier to type than hermaphroditic. My belief is that almost all hermies are genetic females that have weaknesses in their ethylene signaling pathway, which makes them very susceptible to environmental stress.
Stress: Any environmental factor that causes a response by the plant. Stresses can be biotic or abiotic. Biotic stresses include insects, fungi, viruses, predators, and CAMP. Abiotic stresses include drought, poor soil conditions, extreme wind or humidity, or hurricanes or flooding. Both types of stresses can have large effects on phenotype, including induction of intersex phenos.
Hybrid Fertility: The degree to which any two unrelated plants can set seed. For example, crossing an Afghani to a Turk may produce 95% viable seed, whild crossing Durban to Mongolian Indica might only produce 40% viable seed. This is usually a measure of the genetic distance between the parents. The fertility of self-pollinations is unknown but could give the breeder alot of information about the breeding value of the plant in question. A plant that has a desirable phentoype, but is not very self-fertile, is likely very homozygous and will tend to produce consistent offspring.
Micropropagation: Taking very small clones and rooting them in test tubes containing a heat-sterilized nutrient mixture in a agar (gelatin) base. This allows for aseptic (almost sterile) conditioins and precise application of phytochemicals such as STS, auxin, or cytokinin.
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