Breeding (collective information)

Discussion in 'Breeders Paradise' started by SCARHOLE, Oct 23, 2011.

  1.  
    SCARHOLE

    SCARHOLE Well-Known Member

    (Thanks goes out to GreenSupreme for this. Your the man!:mrgreen: )

    I found an old disk from before I ripped out my old hard drive and left the country for a year. There is a bunch of usefull info in there, but yes it is VERY long. But hey what do you want from old Brothers Grim and Vic High info, good score I think. Peace

    OverGrow.Coms Breeding FAQ

    What is combining ability?
    Added by: MR_NATURAL420 Last edited by: Team GrowFAQ Viewed: 3099 times
    Certain inbred lines will display hybrid vigour when crossed. These vigorous lines are said to have favorable combining ability.
    Certain inbreds have the ability to combine well with testers--these have general combining ability (GCA). When the inbred combines well only in certain crosses, it has specific combining ability (SCA). The only way to select for combining ability is to grow and examine the progeny. An astute breeder can recognize the potentital for hybrid vigour by identifying the dominant traits of the parents and deducing which lines may combine favorably.
    Predicting the combining ability of recessive traits can only be determined through progeny testing.
    The breeder is interested in single crosses (also known as F1 generations) that outperform other single crosses. If the breeder has multiple IBLs to work with, she could select first for GCA, then for SCA among the lines with GCA, then identify the best parental gene donors. In most cases with Cannabis you can go directly to selecting for specific combining ability between your IBL and your testers.

    What is hybrid vigour?
    Added by: MR_NATURAL420 Last edited by: Team GrowFAQ Viewed: 2201 times
    When two inbred lines from diferent origins are crossed and the resultant progeny produce a better yield or quality due to a better balance of genes, that is hybrid vigour (heterosis). Not all crosses are an improvement on the parents. Random crosses among random lines will give you random results. Hybrid vigour results when the parents used express favorable specific combining ability.
    Home : Breeding : Strategies

    What are the different types of crosses?
    Added by: MR_NATURAL420 Last edited by: Team GrowFAQ Viewed: 4645 times
    A "single cross" is another name for an F1 hybrid. When two IBLs are crossed the F1 hybrid, or single cross, is the result. This type of cross has the most uniformity and hybrid vigor which makes it the best choice for the home gardener.
    A "double cross" is made by crossing two single crosses which come from four separate IBLs. A double cross will be somewhat more variable than a single cross, but will have a wider range of adaptability. This adaptability makes the double cross good for diverse indoor environments.
    The "top cross" and the "three way cross" are used as testers. A top cross is an IBL crossed with a variety, and it is used to test for general combining ability.(Ed.note:Only GCA can be found in a topcross.SCA is not sought because one half of the topcross is from a single genotype and the other half is from mixed gametes,therefore,one gene donor is unspecified.) A three way cross is an IBL crossed with an F1. The result of this cross will be one of the parents of the double-cross, and it is used to test for specific combining ability.
    A "backcross" is crossing the progeny back to one of its parents,and on another level, to any plant with the same genotype as a Parent. It is designed to improve the parent by retaining most of its qualities and adding a new one. After a series of backcrosses,some degree of uniformity is realized as a result of increased gene frequencies,fixing of some loci through selection and some incidental homozygosity. However, the offspring can only become completely homozygous if the recurrent parent was completely homozygous,and will remain heterozygous for the loci that were heterozygous in the recurrent parent.
    A "self cross" is the result of a female Cannabis plant pollinating herself, whether by artificial induction or natural hermaphrodite tendencies. A female that has produced seed from its own pollen is said to be the S0 generation and the resulting seeds are the S1 progeny.
    A "full sib" cross is a straight male-female cross between brothers and sisters.
    A "half sib" cross uses sister females and unrelated males.


    Uncle Ben's pollination method
    Added by: 10k Last edited by: 10k Viewed: 2223 times
    Contributed by: Uncle Ben
    You have several choices for collecting and using pollen. Males will show as a football-like "ball" on a small, short petiole (stem) at the node sites. Once the pollen pods form, they will elongate via a stem, droop, and the flower bracts will open. After about one week after pollen pods first start to form, or upon complete opening of the male flower bracts, the male anther's will shed pollen which will appear as pale, yellow dust.
    Males do not take much light to survive once they reach flowering stage. Leave your male plant(s) in the grow room until the first male pollen bracts just begin to crack, and then move 'em into another room with a typical 12/12 schedule, this can be simulated with light thru a window or a fluorescent light fixture.
    You have a choice of placing this plant in a very quiet room with no air movement, set on clean paper, or, you can cut the branches off, making a clean slanted cut with a razor blade, and place the branches in a vase of water over paper. Collect the pollen once it begins shedding by placing a glazed ceramic plate or paper plate under the flowers and gently tap the individual branches. Pick out any flowers which tend to drop once in a while.
    The pollen will be like dust, so don't visit the garden until you have taken a bath, or you may end up pollinating plants you didn't intend on pollinating.
    Collect the pollen over time and place it into a clean vial like a film canister. I really like using a paper plate held under a group of flowers, and then gently thumping the stem. After collecting the pollen, the paper plate can be creased, held over a vial, and the sides and edges thumped until all the pollen is shaken into the vial. Shape the paper plate like a creased funnel.
    For a pollen carrier, heat about 2 or 3 teaspoons of flour in an oven set to 180f for 20 minutes or in a small pot set on low heat, let it cool thoroughly, and mix with the pollen to dilute it. I use a ratio of about 1/4 teaspoon pollen to 3 teaspoon flour and have very successful pollination rates. Store in small containers like contact lens cases or film canister, excluding as much air as possible and store in the refrigerator for long term use. Remember, it only takes one male to fertilize one female ovule, and there are millions of pollen cells in a 1/4 teaspoon of pollen so be sure and dilute it.
    Use a small artist brush (my preferred method) or toothpick to pollinate a few of the lower branches which have fresh, white pistils, label the pollinated branches, and harvest your seeds in 3 to 6 weeks. I just cure the seeded branches with the rest of the crop, and tear apart the seeded buds with my fingers. You'll find the seeds close to the stem. Store the seeds in the fridge or freezer, labeled of course, with a little dessicant like silica gel or heat treated (sterilized) rice for long term storage.

    Kryptonite's pollination method
    Added by: Last edited by: 10k Viewed: 3194 times
    Contributed by: Kryptonite
    Collecting Pollen:
    When the first male flowers start to show a possibility of opening, the plant is removed and isolated from the rest of the garden. The male can be placed in a makeshift box, closet, or in an adjacent room.
    It is very important to make sure it is secluded from the female garden and there is absolutely NO possibility of pollen drifting into unwanted areas.
    It is preferable to have sufficient lighting such as a compact flouroescent fixture, or if "Direct" sunlight from a window source is available that may also be adequate.
    The male plant MUST Remain on a 12/12 schedule.
    Through Experimentation I have found that if the male does not have ample lighting it will in most cases cease to finish the flowering cycle followed by complete shutdown of pollen production within several days.
    Pollen is Easily collected by placing a shot glass or similar item under the flower of which you would like to harvest the pollen from.
    Giving a gentle tap to the "ripe" flower with an object such as a pair of tweezers will often cause it to spring open like a parachute and occasionally fall into the glass, "remove them as they fall". It is very important not to let anything that will cause moisture to build in the glass which will result in your pollen caking up on you. Pull the flower from the glass with your tweezers and give it a good tap on the rim of the glass to remove remaining pollen stuck to the flower.
    While harvesting Tap the Flowers gently as not to disturb other male flowers on the plant. An agressive Tap will cause pollen to fall from other finished flowers on the plant resulting in a loss of viable pollen.
    Male flowers open over a period of several days, during this time you should gather what you deem to be enough for your project, working around the plant as the flowers are ready. A little goes a long way.
    It is also helpful if you remove flowers that you have already collected pollen from after each harvest. This is done so that each time you visit your male you can easily Identify Newly ripened flowers.
    It is common to catch enough for a small project over a period of 5 days or so after the male flowers have begun to open. At this time the male can either be discarded, consumed, or cloned for future use.
    "Naturally" the males flower earlier than the females in order to allow for sufficient overlap. By the time you have finished collecting your pollen the girls should be just about ready to be pollenated.
    I would then seclude your best Female for the traits that you want to hopefully preserve from the rest of the garden.
    Pollinate early to insure sufficient time for the seed to ripen, most Indica Strains should be pollinated from 10 to 17 days of 12/12 allowing at least 4 weeks for them to finish. It would be preferable to let them finish with the buds, the longer you let your seed ripen the more viable they will be.
    Applying the collected Pollen:
    If you are not breeding for seed only pollinating the main cola should be avoided, as an example I have personally had excellent results introducing pollen to the secondary colas producing plenty of seed for future use and enough to give to friends.
    Now take a cotton swab and gently dab it into the pollen collecting a small amount on the head of the swab, then hovering over the selected buds "female Flowers" that you wish to pollinate give the q-tip a gentle tap with your forefinger and you will see a golden cloud of pollen drift into the bud, try to avoid touching the "hairs" during flowering, It does harm them making them die and wither off.
    You can control the fall of the pollen by blowing gently in the direction you want it to travel.
    Before placing the girl back into the room make sure you dust it off by blowing excess pollen off of her manually, or you using a hair drying on it's cool setting also works, this will help to insure that you will not have the surplus pollen drifting into unwanted places.
    Another good suggestion would be to let the plant sit "secluded" for several hours after pollination, at this time spray a mist of plain PH corrected water over the entire plant "thoroughly".
    Wetting of the plant will dampen any residual pollen rendering it non-viable and basically useless. Let the plant sit and dry while it is away from the rest of the garden.
    Within 24 to 36 hours you should begin to see the pollinated "hairs" turn reddish or amber, this will show you exactly where to find your seed later.
    It is also a good identifier for finding buds pollinated by any occasional excess pollen.
    Don't rush their finish, let them go!
    I'd hate to see you waste a lot of good bud on immature "green" seeds by not letting them finish fully.
    Another tip: In regards to pollinating the lower branches, make sure that you are getting enough light penetration to the area that you have pollinated, if the buds in the areas which lack ample lighting do not usually finish properly neither will your seed.

    I'd try to always let them go at least 4.5 to 5 weeks.
    The seed is then dried, cured and stored IN the buds, packed neatly in canning jars or bagged in the fridge, taken out as they are needed for use.
    This should be a simple easy to use base for you to get started, but please continue Learning through experimantation. By doing this you will find unique ways of customizing this technique that better suits your needs.
    Good Luck in your Breeding Endeavors, I hope I have helped you OVERGROW The World!!!!



    Soul's Selecting breeding individuals for marijuana production
    Added by: Bongaloid Last edited by: ~shabang~ Viewed: 3297 times
    Contributed by MrSoul:
    Breeding fine cannabis involves carefully choosing the breeding stock. To choose wisely we must first define male and female cannabis:
    Female Cannabis

    Contributed by British Columbia Grower's Association:
    In this first situation, we'll deal with the situation where a plant breeder finds a special individual or clone.
    It's a natural thing to be curious and cross a couple of plants that catch your fancy. Grow them out and find a new variation that you like even better. We can preserve the new variation through cloning indefinately, but accidents happen and clones die. They can get viruses or can suffer clonal deprivation from somatic mutations over time. Plus it's harder to share clones with friends through the mail than seeds. So it's only natural that we would want to create seed backups of this special clone.
    But before we start breeding this clone, we should try and figure what exactly it is we want from the seeds we are going to create. Do we want them to simply be able to reproduce individuals like the special clone? Simple backcrossing (cubing) will accomplish this. Or do we want to to create seeds that will be able to create more seeds like the special clone, a true breeding strain? These are very different in nature. You see, chances are that your special clone will be heterozygous for many of traits she phenotypically expresses. This just means that she will contain genetic information (genes) for two opposing triats, but you can only see one, the dominant one. However, her seeds will only get one or the other of the genes, so her offspring will express all the genetic information she has, including what you can't see within herself. If you want to create a true breeding strain, you need to preserve all the genes you can see, and remove all the genes that you cannot, but may show up in the offspring. Creating homozygosity. The only way to accomplish this is through selection and generational inbreeding (selecting the homozygous offspring to be parents for the next generation).

    BackCrossing and Cubing
    Backcrossing is where you breed an individual (your special clone) with it's progeny. Sick in our world, but plants seem to like it
    1) Your first backcross is just a backcross.
    2) Your second backcross where you take the progeny from the first backcross and cross back to the SAME parent (grandparent now) is often called SQUARING by plant breeders.
    3) Your third backcross where you take the progency (squared) from the second backcross and cross back to the SAME parent (great grandparent now) is often called CUBING by plant breeders. You can continue the backcrossing but we just call this backcrossing. Cubing is in reference to the number three, as in 3 backcrosses
    Cubing works on the basis of mathamatical probabilities with respect to gene frequencies. The more males you use with each cross, the better the chance that your reality matches the theory. In theory, with the first backcross, 75% of your genepool will match the genepool of the P1 parent being cubed. Squaring increases this to 87.5% and cubing increases it to 93.75%. You can arrive at these numbers by taking the average between the two parents making up the cross. For instance, you start by crossing the P1 mom (100%) with and unrelated male (0%) getting 100% + 0% divided by 2 = 50%. Therefore, the offspring of this first cross are loosly thought of as being 50% like the mom. Take these and do your first backcross and you get 100% (mom) + 50% divided by 2 = 75%. And this is where we get the 75% for the first backcross. Same thing applies as you do more backcrosses. As you will see later, you can apply this same probability math to specific genes or traits, and this can have a dramatic effect on your methodology and selection methods.
    Your selection of the right males for each backcross are the crucial points for success with this technique. In each case, you could select males that contain the genes you want, or you could inadvertedly pick those individuals that carry the unwanted recessive genes. Or more likely, you could just pick individuals that are heterozygous for both genes like the P1 mom being backcrossed. The easiest way to deal with this is to start by only looking at one gene and one trait, like lets assume that flavour is determined by a single gene (in reality it's probably not). And do some punnet squares to show gene frequencies through 3 generations of backcrossing. Now lets assume that we found a special pineapple flavoured individual in our pine flavoured population that we wanted to keep. The gene causing the pineapple flavour could be dominant or recessive and the selection abilities and cubing outcome will be different in both cases.
    a) pineapple flavour is dominant.
    P = pineapple flavour and p = pine flavour
    Therefore since each individual will have two flavour genes paired up, the possible genotypes are PP, Pp, and pp. Since P is dominant, PP and Pp will express pineapple flavour while pp will exhibit pine flavour, these are their phenotypes. Now since the pineapple is a new flavour, chances are that the special individual will be heterozygous, or more specifically, Pp. Therefore, the only possible parent combination is Pp X pp with the Pp being the parent to be cubed.
    Figure 1. The F1 cross

    Now most will find it tough to pick males with the gene for pineapple flavour since males don't produce female flowers. Therefore, they will select males randomly and blindly with respect to this trait. The ratio of P to p genes of the male F1 generation to be used in the first backcross will be 2:6. Another way to look at it is to say that the P gene fequency is 25%. This means that one out of four pollen grains will contain the gene for pineapple flavour. Here is how this plays out in the first backcross.
    Figure 2. The B1 cross

    Now it's this first backcross that first creates an individual that is homozygous (PP) for the pineapple flavour. However, again because of our limited selection abilities, we choose males randomly. From the random males we should expect three out of eight pollen grains to to contain the gene for pineapple flavour. The P1 female will still contribute one P gene for every p gene. I'll spare your computor's memory and and not post the table, feel free to do it yorself though on paper to be sure you understand what happening

    The second backcross (Squaring) will produce the following:
    3 PP 8 Pp 5 pp
    Therefore, 68.75% will have pineapple flavour and 31.25% will have pine flavour. The frequency of the P gene has risen to 7/16 or 43.75%.
    And finally, the third backcross (Cubing) will net the following genotypic ratios:
    7PP 16Pp 9pp
    Therefore, 71.875% will have pineapple flavour after cubing has been completed. Roughly 22% (7/32*100) of the cubed progeny will be true breeding for the pineapple flavour. The frequency of the P gene has risen to roughly 47% (30/64).
    In conclusion, if the backcrossing continued indefinately with random selection of males and with large enough of a population size, the frequency of the P gene would max out at 50%. This means that the best that can be expected from cubing is 25% true breeding for pineapple flavour and 75% that will display the pineapple flavour. You would never be rid of the 25% that would maintain the pine flavour. This model would hold true when trying to cube any heterozygous trait.

    b) Pineapple flavour is recessive
    In this case, P is for the pine flavour and p is for pineapple flavour. Convention is that the capital letter signifies dominance. For the breeder to have noticed the interesting trait, the mom to be cubed would have to be homozygous for the pineapple flavour (pp). Depending where the male came from and whether it was related, it could be Pp or PP, with PP being more likely. It won't make much difference which in the outcome.
    F1 cross is pretty basic, we'll skip the diagram. We simply cross the female (pp) with the male (PP) and get offspring that are all Pp. Since the pine flavour is recessive, none of the F1 offspring will have pineapple flavour (hint ). However, the frequency of the gene p will be 50%.
    pp X PP = Pp + Pp + Pp + Pp
    Since the F1 generation are all the same (Pp), the pollen it donates to the first backcross will contain a p gene for every P gene. The first backcross will be:
    B1 = pp X Pp = Pp + Pp + pp + pp
    As you can see, 50% of the offspring will be pineapple flavoured and the frequency of the p gene is 6/8 or 75%. This B1 generation will generate pollen containing 6 p genes for every 2 P genes.

    Figure 3. The second backcross.

    As you can see, the second backcross or squaring produces pineapple flavour in 75% of the offspring. And the p gene frequency within those offspring is roughly 88%. (Remember C88 ). Of the pollen grains from this squaring, 14 out of 16 will carry the p gene for pineapple flavouring. When they are backcrossed to the P1 mom for the third time, they net the following cubed progeny:

    Figure 4. The third backcross

    After cubing of a homozygous gene pair, we end up with roughly 88% of them displaying the desired trait (pineapple flavour in this case) and also being true breeding for that same trait. The frequency of this desired gene will be roughly 94%. If the backcrossing was to continue indefinately, the gene frequency would continue to approach 100% but never entirely get there.

    It should be noted that the above examples assume no selective pressure and large enough population sizes to ensure random matings. As the number of males used in each generation decreases, the greater the selective pressure whether intended or not. The significance of a breeding population size and selective pressure is much greater when the traits to be cubed are heterozygous. And most importantly, the above examples only take into account for a single gene pair.
    In reality, most of the traits we select for like potency are influenced by several traits. Then the math gets more complicated if you want to figure out the success rate of a cubing project. Generally speaking, you multiply the probabilities of achieving each trait against each other. For example, if your pineapple trait was influenced by 2 seperate recessive genes, then you would multiply 87.5% * 87.5% (.875 * .875 *100) and get 76.6%. This means that 76.6% of the offspring would be pineapple flavoured. Now lets say the pineapple trait is influenced by 2 recessive traits and and a heterozygous dominant one. We would multiply 87.5% by 87.5% by 71.9% (.875*.875*.719*100) and get 55%. Just by increasing to three genes, we have decreased the number of cubed offspring having pineapple flavouring down to 55%. Therefore, cubing is a good technique where you want to increase the frequency of a few genes (this is an important point to remember ), but as the project increases, the chance of success decreases .... at least without some level of selective pressure.

    Applying the pressure
    The best way to significantly increase your chances of success is to apply intended selective pressure and eliminate unintentional selective pressure. Try to find clearcut and efficient ways to isolate and select for and against certain traits. Find ways to be sure your males are passing along the intended traits and remove all males that do not. This includes ALL traits that may be selected for. Some traits you will be able to observe directly in the males. Other traits like flowering duration you may not. If you are selecting for a trait you can't directly observe, you want to do some progeny tests and determine which males pass on the most desireable genes. I'll explain more on progeny tests later.
    It's important that when chosing your best males to ignore the superficial traits having nothing to do with the real traits your looking for. You see, cannabis has several thousand genes residing on just 10 chromosome pairs or 20 individual chromosomes. Therefore each chomosome contains hundred of genes. Each gene residing on the same chromosome is said to be linked to each other. Generally speaking, they travel as a group . If you select for one of them, you are actually selecting for all of the traits on the chromosome. There is an exception to this rule refferred to as breaking linked genes via crossing over, but for simplicity sake, we will ignore that for now. Getting back to selection, you could decide to select for a trait such as you like the spikey look of the leaves while really being interested in fixing the grapefruit flavour. But as it may happen, both traits may be on the same chromosome pair but opposite chromosomes. If so, as long as you select the plants with spikey leaves, you will never get the grapefruit flavour you really want. It's good to keep in mind that each time you select for a triat, you are selecting against several hundred genes This is why most serious breeders learn to take small methodical steps and work on one or two traits at a time. Especially with inbreeding projects such as selfing and backcrossing.
    Now lets see what kind of improvements we can make in the first example of trying to cube a heterozygous dominant trait using some selective pressure. Lets say that with each generation, we are able to remove the individuals recessive for the pine flavour (pp), but can't remove the heterozygous ones (Pp). If you recall, our P1 mom had the genotype (Pp) in that model and the F1 cross yielded (Pp + Pp + pp + pp) as possible offspring combinations. We remove the two (pp) individuals leaving us with only Pp. Therefore our first backcross will be:
    Pp * Pp = PP + Pp + Pp + pp
    Again we remove the pp individual leaving us with PP + 2Pp. Going into the second backcross we have increased our P gene frequency from 37.5% up to 66.7%. This means that going into the second backcross 4 of every six pollen grains will carry the P gene. The outcome is as follows

    As you can see, after selecting against the homozygous recessives for 2 backcrosses, we have increased our P gene frequency to 58% from 44% in our squared population. If we again remove the homozygous recessives, our gene frequency increases to 70% (14/20) going into the third backcross, meaning that 7 out of 10 pollen grains will carry the P gene. Again, I'll spare your PC's memory and just give your the results of the third backcross.
    B3 cross = 7 PP + 10 Pp + 3 pp
    This translates to mean that 95% of the progeny will taste like pineapple after cubing a heterozygous dominant strain if the homozygous pine tasting ones are removed prior to to each backcross. This is an improvent from 72% when no selection occurred. The frequency of individuals true breeding for the pineapple flavour rose to 35%. But more importantly, the P gene frequency improves to 60%. This will be an important consideration when we discuss progeny testing .
    But for now lets recap the percentage of individuals true breeding for the pineapple taste in each of the models. In the case where the pineapple flavour trait is heterozygous dominant and no selective pressure is used, cubing produced 22% true breeding individuals. By selecting against the homozygous pine recessive, we were able to increase this too 35%. And finally, when cubing a homozygous recessive gene, we are able to achieve a cubed population that is 87.5% true breeding for the pineapple flavour. And as I pointed out earlier, these numbers only apply to single gene traits. Lets say the pineapple flavour is coded by two seperate genes, one dominant and one recessive, and you are able to select against the homozygous recessive pine flavour while selecting for the dominant pineapple flavour gene. Your cubed population would then contain 87.5% * 35% (.875 * .35 * 100) = 30% true breeding individuals. As you can see, as long as the cubed source is heterozygous, it doesn't matter how many backcrosses you do, you will never achieve a true breeding strain.




    What is cubing?
    Added by: Team GrowFAQ Viewed: 1457 times
    Contributed by MrSoul:
    An alternative F1 hybrid breeding method I
    Contributed by Vic High:
    What really is an F1 cross?
    Well defining the terms P1, F1, F2, homozygous, and heterogygous can be a simple task, however, applying them to applied genetics can often create confusion. Depending on your point of reference, a plant could be described as any of these terms. For our specific field of interest it's important to further define these terms to reduce confusion and protect the consumers. First I'll provide the classic scientific definition of these and other related terms and then I'll dive into each term into detail.
    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 cant 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. (Ed.note:The textbooks consider this a 'double cross'.)
    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.
    Note: this is a rough draft to be published to the internet. Hopefully in time it or something similar will be used to help establish an industry standard. Any comments and critism is welcome to aid in the production of the final draft. Small steps like this can only benefit the cannabis community over the long haul.
    REFERENCES:
    Clarke RC. 1981. Marijuana Botony Ronin Publishing, California
    Colangeli AM. 1989. Advanced Biology notes. University of Victoria, BC
    Futuyma DJ. 1986. Evolutionary Biology Sinauer Associates, Inc. Massachusetts
    Klug & Cummings. 1986. Concepts of Genetics 2nd ed. Scott, Foresman, & comp. Illinois
    Grossnickle & Russell. 1989. Stock quality improvement of yellow-cedar. Canada-BC Forest Resources Developement Agreement (F.R.D.A.) Project 2.40
    Watts. 1980. Flower & Vegetable Plant Breeding Grower Books, London
    Wright JW Introduction to Forest Genetics Academic Press, San Francisco


    What is linkage?
    Added by: MR_NATURAL420 Last edited by: MR_NATURAL420 Viewed: 989 times
    Genes located on the same chromosome are not randomly assorted but tend to be inherited together. This is known as linkage. Plants depend on a large number of factors for their phenotype and linked factors are usually dominant. Linkage adds to the difficulty of combining favorable factors of parents of a cross. Large populations are needed to obtain recombination and find that rare but desirable individual.








    (Did you notice UncleBens Pollination method in there?)
  2.  
    fatboyOGOF

    fatboyOGOF Well-Known Member

    nice find! i miss the great and mighty shabang!

    i bought 2 of mr souls strains in the mid 90s. they were my first store bought genetics: apollo 13 and cinderella 88. i'm still growing out the F2s! :)
  3.  
    Springtucky

    Springtucky Active Member

    :clap:
    sticky this
  4.  
    boneheadbob

    boneheadbob Well-Known Member

    I noticed UB and I actually read it all looking for "How to pick a male and female for dummies"
  5.  
    SCARHOLE

    SCARHOLE Well-Known Member

    Some Kick ass folks saved alot of the OverGrow.com Faq from Google cache.
    They have the other half of the Breeding FAQ.
    Thanks for the heads up on this WoodsmanToker!!!!!!!

    Ill put it up here for yall .....









    Originally posted by S2 at The Graden's Cure
    2008-01-11 01:13
    Recovery of the Overgrow GrowFAQ

    Almost 2 weeks ago one of the great Marijuana Cultivation Resources available on the Internet went dark. Overgrow.com was home to the finest Marijuana GrowFAQ available on the Internet and it too went dark with its host. Fortunately, Google had a decent cache of the Overgrow GrowFAQ data, minus the images. I’ve created a series of scripts to retrieve as much of this data as possible from the Google Cache.
    Due to the complexities of some of the GrowFAQ records, a portion of the FAQ was simply unrecoverable using my programming skills. However, I am confident that I have recovered more than 3/4ths of the OG GrowFAQ. It’s important to remember that the recovery was limited to the data that Google had stored in its cache. I found this cached data to be full of duplicate entries and partial HTML pages which I was unable to retrieve.
    I am now making the entire 524 recovered GrowFAQ entries publicly available to anyone who wishes to download them. I have made the entire GrowFAQ available as a single XML document available for download by clicking here (2,430 KB). If you are not familiar with XML or simply do not wish to duplicate the entire GrowFAQ you can find each individual entry listed here at growfaq.marijuana.com. I will be turning this over to the administration of HempCultivation.Com for further development and image replacement.
    You will find that this GrowFAQ environment has several features that allow you to save information that you believe valuable. You can save each individual FAQ as a PDF file, XML file or simply print it out. You may comment on each individual faq to give further information or advice as well as rate each faq for its usefulness.
    It is my hope that we can pick up where OG left off and keep this document alive for everyone to share. Help us grow the faq by asking a question or by answering one left by a visitor. This FAQ is what you make of it – there’s a solid foundation to build upon here.







    ID #1006
    What is an F1, F2, and IBL?

    An IBL (inbred line) is a genetically homogeneous strain that grows uniformly from seed.

    A hybrid is a strain made up of two genetically unlike parents, IBL or hybrid.

    When you cross two different IBL strains for the FIRST time, it is called the F1 generation. When you cross two of the same F1 hybrid (inbreed), it is called the F2 generation.

    The process of selective inbreeding must continue at least until the F4 to stabilize the recurrently selected traits. When you cross two specimens of an IBL variety, you get more of the same, because an IBL is homozygous, or true breeding for particular traits.





    How can I contribute as a sativa breeder?

    Just as we all benefited from SSSC and their networking of local European and North American seed breeders in the 1980's, we would benefit by a cooperative network breeding sativa or sativa dominant strains, stabilizing strains obtained in the country of natural origin and developing hybrids and stable strains from them. It will be space and time consuming, but these genetics would definitely have a large market. This concept would truly be an important undertaking.

    My wish list includes strains from Australia, Brazil, Cambodia, Columbia, Ethiopia, India, Hawaii, India, Indonesia, Jamaica, Mexico, Nepal, Nigeria, Panama, Peru, South Africa, Swaziland and Vietnam. Some may have other desirable genetics to add to this pure sativa gene pool. The Federation brought forward some unique pure sativa and double sativa hybrids with the Golden Triangle Thai and Celestial Temple Sativa along with their trademark Hawaiin Sativa. African Seeds and the Dutch seed banks offer various sativa from around the world. Pure Haze would, of course, have to be in the genetic pool. Certain sativas are not so long flowering and unwieldy they could not be used to produce nearly pure sativa hybrids and IBL's that were suitable for indoor growers also. Making hybrids of pure sativas with strains like AK47, Cinderella99, Genius, Jack Herer, Super Silver Haze and Skunk 1 would introduce potent sativa type genetics with more desirable structure and shorter flowering periods.

    This will require dedication, time and hard work from people around the globe that are willing to travel to the locations not represented to acquire the seed stock. Individuals with a nose for adventure could spend some time making point of origin acquisition of the genetics for such a venture. It would not be too far fetched to visit some of these countries for adventurous people from places all over the world. Take a "vacation", if you make some connections, score some good local bud and see if any viable seeds are present. Many native land race strains have remained pure, while others have had outside genetics introduced. The older local growers in the region and educated breeders and growers would be in the best position to vouch for purity. If they obtained something of quality, vacationers could examine their "score" for seeds and consistency of the buds and send them home to evaluate. The indigenous strains of the countries listed are under represented in the overly reconstituted gene pool offered to us.

    The larger scale outdoor growing to perform selective breeding is best suited to the tropics and greenhouses. Australia, Spain and their neighbors offer excellent weather conditions and proximity to local sativa land races for people living there. Africa, Southeast Asia, and India offer many unique genetics that should be worked with by experienced breeders and growers. Many individuals working in their corner of the world, developing strains and producing seed. The potential for meeting people who's locality has indigenous strains that have been cultivated for drug uses for many generations. These strains are needles in the haystack that need to be rediscovered and bred further.
    The concept of seed archiving is important. There may be enough sativa strains in the hands of educated growers to probably fill all the locales on my wish list. Genetic diversity and continuance could be maintained indefinitely, if we organize a community of growers and breeders. Let's all put the time and effort into making strains available to everyone who wants them by forming a cooperative. The program goes as far as people are willing to contribute their own time and effort, not just people giving their seeds to others to grow. Sativa are like children...you have more patience and hope for your own. The idea is for people with the ability to set aside some time and space to perpetuate sativa genetics and hopefully come up with some special individuals to breed. It is my desire that individuals take the initiative to work with what is available to them.





    How should strains be named?

    In the horticultural world, the order of naming in hybrids should be Female X Male. Many breeders and retailers practice improper naming protocol. I have seen too many obvious discrepencies in commercial Cannabis naming practices to give any validity to the standard protocol as a way to determine the parentage. Breeders and retailers should correct this.

    When choosing a name for your prize breeding project, it is important to be original and not be confusing. Unfortunately, some seed breeders are using names for their newer and different offerings already taken by strains currently held by other seedbanks. This is definitely something that is deceptive and troublesome. Introducing a different strain under another, now famous name appears to be an attempt to ride on their coattails. It is terribly confusing and misleading to the consumer for another company in the same market to decide to use the same name for a newer and different product. What if VW decided their new sports car was going to be called a Corvette because they are based in Europe and they like the name? They have lawyers for this.




    ID #1021
    What is hybrid vigour?

    When two inbred lines from diferent origins are crossed and the resultant progeny produce a better yield or quality due to a better balance of genes, that is hybrid vigour (heterosis). Not all crosses are an improvement on the parents. Random crosses among random lines will give you random results. Hybrid vigour results when the parents used express favorable specific combining ability.




    How do I select for combining ability?
    The ONLY way to select for combining ability is to test for it.

    Even though there is a positive relation between overall vigour of an inbred and the yield of its crosses, the combining ability is more important. The breeding value of a certain hybrid is determined by studying it's progeny.

    Making an inbred-to-varietal cross (top cross) is one way. Cross the various lines to a stable variety (Skunk no.1, Northern Lights, etc.) and the progeny that produces the best crosses is selected. Repeating the test in different locations will eliminate any possible influences the environment might produce, and repeating the test with different testers would ensure that the results were accurate.




    Does it matter which line is used for the male?

    No. Some growers swear that certain plants do better as one parent or the other, but it really doesn't matter as yield and quality are due to that particular cross and remain the same whenever that cross is repeated. Genetically the siblings in an IBL are the same no matter which gender is used.




    What should I look for in an IBL?

    First define your goals. Are you growing for yourself or for commercial production? Indoors or out? Mostly sativa or mostly indica? Keep only the plants that have the qualities you want, and mercilessly kill the rest.

    Select plants that don't fall over; if you have to prop them up with toothpicks, you might as well cull them. Keep the ones that are free from abnormalities and hermaphroditism. Hopefully you've got enough many seeds to be ruthless. Keep the ones that show better resistance to disease and pests. Even though the progeny performance is more important than the individual, there is a positive relationship between the overall vigour of an IBL and the yield of its hybrids. If they produce vigourous plants they are more likely to pass these traits on.





    What is recurrent selection?

    Recurrent selection refers to selecting for certain traits generation after generation.

    With the interbreeding of reselected plants, the breeder can access favorable recombinations as well as stabilize traits within the genepool. Select your ideotype in each IBL, but don't be totally reliant on the phenotype because its not always indicative of the actual genotype. Make yield and quality trials with test crosses and select the best ten lines. Intercross and repeat.

    After recurrent selection is done, select new individuals to be the new parents of IBLs. These are then recurrently selected for four or five generations. After recurrent selection has been done in two seperate programs, an F1 single cross of the two lines (A X B) is then produced.

    In reciprocal recurrent selection (RRS), pollen of multiple A males is used to pollinate ideal B females and pollen of B used to pollinate ideal plants of A. Thus A is used as a tester to select for the combining ability of B plants, and B is a tester for A. At the same time,inbred seedlots(A X A) and (B X B) are made,using mixed male pollen and the best females of each population. Store the resulting seed-- the seedlines with the best combining ability will be used as parents of the next RRS cycle.

    The (A X B) hybrid progeny are simply used as visual indicators of the combining ability that lies in the saved seeds.These specific inbred parental lines are kept in reserve until the progeny testing of the different (A X B) hybrids has shown which has better SCA and will make the better hybrids. Since this is such a complicated strategy, good note taking and organization are definitely required.





    What is convergent improvement?


    If you have a good single cross (A X B), and you know the vigour is the result of the dominance of growth factors, back-cross it several generations to A, selecting for qualities of B that are lacking in A. After two or more generations of back-crossing and selecting, IBLs are produced. Do the same for B. After improved A and B are obtained, they are tested in crosses and compared to the original (A X B). Multiple convergence is improving an inbred by convergence of gametes from different sources. If A is a very desirable inbred in crosses, it can be modified in two seperate back-cross programs {eg. (A X C) X A, and (A X D) X A}, with the idea that the improved inbreds will be vigourous enough to use as the male parent of a double-cross.





    What are gametes and zygotes?

    The gamete of the male is the pollen grain, the gamete of the female is the embryo sac. Gametes contain half of the genes of an adult plant and unite to form the zygote. After mitosis the zygote becomes the embryo of the seed.




    How do I select a male?

    The only way to determine the value of a plant for breeding is to grow and examine its progeny. The most potent plant might not pass on this trait, and the healthiest plant might not have favorable combining ability. Judging a male by visual appearance and also smoke testing, or using bio-assay, should not be discounted, but test crossing the male is the





    What is a bio-assay?

    A bio-assay is using a living organism to determine the qualities of a substance-- smoke testing your males or females. Have ten of your friends rate each sample based on your critera.





    ID #1064
    Can I breed effectively indoors?

    Well, if you're thinking you can create farm-quality double crosses, the answer is probably no. It takes selection from hundreds of plants to find the right parents to use. Even without a lot of space for selection, you can do better than making random crosses.

    Seedling selection for visual traits will help save space, but this is only useful at the start of breeding. When beginning, start as many seeds from the material to be used as you can so that you have a large enough base to select from. Take at least two clones from each plant, and keep them in the veg stage. Use bonsai methods to keep everything small.

    Once you've selected the plants to use for the next generation, discard all of the other clones of the seedlings not chosen. Don't be sentimental, just do it.

    Keep good notes, it's easy to get confused, especially when you're high. The down side is that you'll have to be happy with a hundred tiny, seedy plants, instead of big sinsemilla buds. Also if you're not exceeding mandatory minimum sentencing (it's for a good cause, your honor), you're not selecting from enough plants. I know, it's crazy, you might only get a couple grams per plant, with the seeds and all, but its still a hundred plants. Until some one goes to court to set the precedent, I'm assuming 1 plant plus 99 tissue culture vials would be 100 plants, but I don't know. Maybe, you could tell them they are venus flytraps. :)




    What is the nomenclature of Cannabis?


    Nomenclature is the method biologists use to precisely define the relationship of an organism. Common names are not descriptive enough. When I say "grass", more than one thing comes to mind, so you need a way to narrow it down.
    The genus is always capitalized and the species is not: Cannabis indica
    When the genus is mentioned frequently, it is often abreviated: C. indica
    When there is a sub-species it is distinguished like this: C. indica ssp. kafiristanica
    A variety is indicated by: C. indica var. afghani
    A land-race, or "form", isn't different enough to be a variety and it is written like this: C. indica f. maple-leaf
    Any plant that is in cultivation (a cultivar, clone or hybrid) is capitalized and seperated by quotation marks: C. indica "Super Skunk"
    Inbred lines are indicated by an alpha-numeric figure: NL#5
    There is disagreement among biologists as to whether Cannabis should be divided into species or not, but for practical purposes we usually divide it into C. indica, C. sativa, and C. ruderalis. C. indica has wide leaves and either a cadelabra shape or a dominant main cola. C. sativa is a tall plant with many branches and is either bamboo shaped or christmas tree shaped. C. ruderalis is a small plant with little THC that flowers independant of the photoperiod.

    [Editor's note: It is widely accepted that genus Cannabis comprises a single species, Cannabis sativa, which consists of 2 or 3 subspecies: C. sativa subsp. sativa, C. sativa subsp indica, and possibly C. sativa subsp. ruderalis. This is called the Linnaean classification (after Carolus Linnaeus), and is usually denoted as such by including a capital L after the species name (i.e., Cannabis sativa L). Many recognized authorities, including RC Clarke, support this classification, which is also legally recognized in the US and elsewhere.
    However, this system of classification has been much debated, with many advocates of classification as multiple species. Based on genetic analysis publshed in 2005, it has been proposed that low-THC (fiber) varieties be classified as species C. sativa, that narrow- and broad-leaf drug varieties be classified as species C. indica.
    Yet another proposal is that the genus comprises a single species, with fiber varieties in subsp. sativa, narrow-leaf drug varieties in subsp. rasta, and broad-leaf drug varieties in subsp. indica.
    Regardless of the classification system used, it is generally agreed that the different varieties of Cannabis interbreed freely.]





    How long can I store pollen?

    If stored dark, dried and cool you are safe keeping pollen 3 to 4 days. It is difficult to keep viable being highly susceptible to molds.




    ID #1171
    When should I pollinate my female?


    Contributed by Mrsoul: The way to decide when to pollinate the female is by counting BACK from the end of her flowering period 4 weeks...this allows the seeds enough time to mature before harvest.
    The seeds should be allowed to dry in the buds after harvest, as they do continue to mature during the drying process.




    How do I pollinate?


    A clean q-tip or craft paintbrush is effective. Wait at least 3 to 4 days to determine whether fertilization was successful.
    Soul recommends removing the female to be pollinated from the grow area to pollinate. After 3 to 4 days spray the pollinated plant with water to kill any residual pollen and return to the flower room. Soul recommends pollinating 4 weeks before the female plant will finish. He also suggests not removing the seeds from their buds until the buds are completely dry, as they will continue to mature after harvest.




    How do I create a true breeding strain?

    Contributed by Vic High:

    I've been hearing a fair bit of confusion from many on how to create a true breeding strain and so I'm writing this page to try and help shed some light on the subject. There are a few situations where a plant breeder would want to create a true breeding strain (IBL) and a few ways of accomplishing the task. But understanding the subtle differences of the various techniques is not so easy. This paper will attempt to give a basic understanding of what is actually happening with each technique and then apply what is learned to actual projetcs. As a friend worked overtime making sure I didn't forget, breeding is not a black and white subject and as a whole, it would be too complex to put on paper in an easily understood form. Therefore, I will create small fictional examples to reinforce various concepts and then we will take those examples and concepts and apply some reality to them. Try not to get hung up on the erroneous assumptions used here such as flavour being monogenic, the assumption is simply used to make it easier to learn a certain concept.


    Just What Is It That We Are Doing?

    Before we dive in, maybe we should take the time to understand what we are trying to accomplish when we set out to create a true breeding strain. There are hundreds of possible phenotypic traits that we could observe within a cannabis population. Are we trying to make all of them the same and remove ALL variation? Not likely, the genetic code is just too complex to try. Plus, since phenotype (what we see) is 1/2 genotype + 1/2 environment, everytime the population was grown under new conditions, new heterozygous traits would be observed. Basically, all we are trying to create is an overall uniformity while not worrying about the minor individual variations. No different than a dog breed. You can look at a german shepard and recognise it as belonging to a discrete breed. But if you look closer at several german shepards all at the same time, you will find variations with each and every one of them. Some will be a little taller, some a little wider, some more agressive, some a little fatter, some darker, etc. But they would all fall within an acceptable range for the various traits. Generally speaking, this is what a plant breeder is trying to accomplish when creating a true breeding strain, or IBL.

    However this isn't always the case. Sometimes a breeder will just concentrate on a specific trait, like say outdoor harvest date, or mite resistance. You could still have a population where some are 2' bushes and some 10' trees. In this case, you would say that the strain was true breeding for the particular trait, but you wouldn't consider it true breeding strain per se. In genetics, wording plays a big part in meaning and understanding. As does point of reference as my F1 vs F2 comparison page illustrates.

    Ok, so we want to make a cannabis population fairly uniform over a few phenotypically important traits, like say flavour for instance. For simplicity sake, we'll just deal with the single trait flavour, it's complex enough. And although flavour is controlled by several gene pairs (polygenic), we'll make the simplistic assumption that it's controlled by a single gene pair (monogenic) for many of the models and examples in this paper. There are many flavours such as chocolate, vanilla, musky, skunky, blueberry, etc, but in this paper we'll just deal with two flavours, pine and pineapple. Either gene in the gene pair can code for either of the flavours. If both genes code for pineapple or both genes code for pine flavour, we say that the gene pair (and individual plant) is homozygous for flavour. If the one gene codes for pine and the other codes for pineapple, we say that the gene pair (and individual plant) is heterozyous with respect to flavour. The heterozygous individual can create gametes (pollen or ovules) that can code for either pine flavour or pineapple flavour, the homozygous individuals can only create gametes that code for one OR the other. A homozygous individual is considered true breeding and a heterozygous individual is not.

    However, as the words imply, when we are creating a true breeding strain, we are looking at a population, not individuals. We are trying to make all the individuals in the population homozygous for a particular trait or group of traits. Lets say we have a population of 50 individual plants, and each plant has has a gene pair coding for flavour. That means that 100 flavour genes make up the flavour genepool (reality is much more complex). When trying to create a true breeding strain, we are in fact trying to make all 100 of those genes code for the same trait ( pineapple flavour in our case). The closer our population comes getting all 100 genes the same, the more homozygous or true breeding it becomes. We use the terminology gene frequency to measure and describe this concept, where gene frequency is simply the ratio or percentage of the population that actually contains a specific gene. The higher the gene frequency, the more true breeding the population is. A fixed trait is where the gene frequency of the trait reaches 100%.

    And folks, this is the basic backbone of what breeding is all about, manipulating gene frequencies. It doesn't matter if your making IBL, F1s, F2s, selecting for this or selecting for that, all you are really doing is manipulating gene frequencies. Therefore, to ever really understand what is happening in any breeding project, the breeder must pay attention to gene frequencies and assess how his selective pressures and models are influencing them. They are his measure of success.


    What are we trying to create a true breeding strain from?

    This a good question. Sometimes a gardener will notice a sport or unique individual in an F2 population, like say it has pineapple flavour when the rest have pine flavour. For one reason or another he decides he wants to preserve this new trait or combination of traits from that single individual. For the sake of ease of comprehension, we tend to call this special unique individual the P1 mom. He could start by selfing the individual OR breeding that individual with another and create what can be described as F1 offspring. If the F1 route was chosen, then breeders can diverge down two new paths. Some breeders will take the progeny of the F1 crossing and breed it back to the P1 mom, and then repeat for a couple more generations. This is referred to as backcrossing or cubing by cannabis breeders. Another common strategy is to make F2 progeny from the F1 population and then look for individuals that match the P1 mom. They would repeat the process for a few generations. We can call this filial or generational inbreeding since the parents from each cross belong to the same generation.

    In another situation, sometimes a farmer will notice a few individuals in his fields that stand out from the crowd in a possitive manner. Like say the are resistant to a problem pest like powdery mildew. In this case, he will collect the best of the individuals and his starting population will contain several similar individuals and not a unique single individual as in the previous example. He would skip the hybridizing step (making the F1s) and go straight to the generational inbreeding step. Links to pages going into detail of each of these basic techniques and their impact on influencing gene frequencies are at:

    A) Selfing the individual

    B) Backcrossing and Cubing

    C) Filial or Generational Inbreeding from an individual

    D) Filial or Generational Inbreeding from a group


    Applying the Pressure
    Another excellent method to influence gene frequencies is to apply selective pressure. The idea here is to select only individuals that carry the desireable genes, and discard the rest.


    A) Principles of selection
    B) Progeny tests







    What is selfing?

    Contributed by Vic High:

    As the title implies, the main drawback to selfing cannabis plants is that you loose the male portion of your population, making future crosses difficult. Some think that by selfing a plant, all the offspring will turn out just like mom. That is only true if mom is true breeding for all the traits you are interested in. Otherwise, her offspring will show two phenotypes for every trait that she is not true breeding.

    There are two basic models for selfing a plant such as cannabis the first one being where the plant is homozygous for the trait in question. Let's assume again that pineapple flavour is controlled by the recessive gene pp. If we self the plant we fill get the following S1 cross.

    S1 cross = pp x pp = pp + pp + pp + pp or 100% pineapple flavoured female offspring. But no matching males

    The other likely possibility is that special individual heterozygous dominant for the pineapple flavour. In this case P will indicate for pineapple flavour and the S1 cross will be:

    S1 cross = Pp x Pp = PP + Pp + Pp + pp, our familiar 1:2:1 mendelian ratio.

    In this second example only 75% of the offspring will have pineapple flavour and the frequency of the P gene will only be 50%, a far cry from 100% or true breeding. From here on, this isn't much different from a half sib cross involving regular inbreeding or backcrossing. It will take a few generations to achieve something close to true breeding, but as with backcrossing, as long as we use the P1 mom in the crosses (selfing in this case), we will never achieve a true breeding population.





    How important is male selection when cubing?

    Contributed by Vic High:

    Basically, when you are cubing a mother plant, you are taking her paired alleles and making them homozygous for each trait that you want to become true breeding. Some paired alleles will already be homozygous but most of the important ones will be heterozygous in the case of an F1 other-to-be-cubed. Mind you this can only be true of those traits that are controlled by basic dominant/recessive genes. This isn't always the case and sometimes genes can be codominant. Here is an example of the implications.

    let A & B & C be codominant genes, d being a recessive gene on the same loci. Now for simplicity we will just look at the genotype and ignore the phenotypic effects of each genotype. Lets say our mother-to-be cubed has the genotype AB and the P1 male is Cd (both being F1s).

    Notice that you can never really get a completely true breeding situation with this sort of gene. To fully capture the mother's trait you must maintain the heterozygoous AB condition. Crossing two parents with the same characteristic AB will give the following offspring:

    AA, AB, AB, BB

    Note only 50% of the offspring will ever be able to recreate this mother's genotype (and in this case phenotype)

    Ok, now that aside, lets explore the practical issues of trying to cube that mom. Crossing the AB and Cd you the following combinations:

    AC, Ad, BC, Bd. You then select from these to do your first backcross to your AB mom (creating the .75 generation)

    ABxAC = AA, AC, AB, CA - 25% resemble mom in this case
    ABxAd = AA, Ad, AB, Bd - 25% resemble mom again
    ABxBC = AB, AC, BB, BC - 25% resemble mom again
    ABxBd = AB, Ad, BB, Bd - 25% resemble mom again

    As you can see, it really doesn't matter which males you selected for your first backcross as they all brought you equally close to your goal. Notice that it will also take a sharp eye to pick out the special offspring that will take you closer to your goal in the second backcross. Hopefully this shows how difficult it can be to stabililize a trait caused by codominant genes.

    This was just the first factor affecting cubing success. Also, it only dealt with a single genes and you are often trying to stabilize dozens of gene pairs when cubing.







    What is the difference between an F1 and a hybrid?

    Contributed by Vic High:

    What really is an F1 cross?

    Well defining the terms P1, F1, F2, homozygous, and heterogygous can be a simple task, however, applying them to applied genetics can often create confusion. Depending on your point of reference, a plant could be described as any of these terms. For our specific field of interest it's important to further define these terms to reduce confusion and protect the consumers. First I'll provide the classic scientific definition of these and other related terms and then I'll dive into each term into detail.

    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 cant 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. (Ed.note:The textbooks consider this a 'double cross'.)

    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.

    Note: this is a rough draft to be published to the internet. Hopefully in time it or something similar will be used to help establish an industry standard. Any comments and critism is welcome to aid in the production of the final draft. Small steps like this can only benefit the cannabis community over the long haul.
  6.  
    Izoc666

    Izoc666 Well-Known Member

    very good information !! nice job , sir.

    666
  7.  
    SCARHOLE

    SCARHOLE Well-Known Member

    Lucas' pollination method

    Contributed by: Lucas

    To determine pollination timing, start the male and the female clones under 12/12 simultaneously. Expect 3 to 4 weeks to elapse before you have pollen ready. Pollinate at this time, because seeds need 4 weeks to mature. A seed is mature when it is dark and hard, and does not crush when pinched.

    The grower at a local medical club, did a test with Apollo in a bubbler using the above timing. They planted 3 distinct female clones and 1 male in the lid of a 10 gal rubbermaid, using 3" netpots. The male was reduced to a single branch, being sure to leave the large fan leaves to provide health and vigor. (If you let a pruned male get shaded out it can die, you must keep it well lit).

    The top 6" of the male branch was bagged, using a brown paper bag with a clear plastic window. The bottom of the bag was taped shut completely, sealing to the stem. The top was also sealed, except one corner was clipped off, leaving a hole about the size of a dime. Pollen collected around the stem, in the bottom of the bag. There was no pollen escape from the breather hole. The grower would shake the pollen down into the bag, while pinching the breather hole shut, on a daily basis. After about a week of active pollen drop, the stem was cut off below the bag, and outside the room, the top of the bag was cut open. The male top was removed from the bag, which collected pollen sacks and debris still in the bottom. This excess pollen and debris was dumped out into a ziplock.

    The pollen collecting bag was then carried into the grow and slipped over a single female cola and rotated around and wiggled a bit. This cola developed lots of seed. There was no stray pollination. Using a paintbrush and the ziplock of pollen, some selected buds on the other clones were pollinated as well. Again, no unexpected stray seeds. Of course oscillating fans, if you use them, should be off during painting and bagging. I do not recommend misting with lights on.





    How do they get strains to taste different?


    The different tastes of certain strains of cannabis are a product of controlled-breeding programs. The flavour and smell of Cannabis comes from five substances: mono- and sesqui-terpenes, alpha- and beta-pinene, limonene, myrcene, and beta-phalandrene. The amount of each substance present in a given strain will determine the flavor and smell.






    What is the probability that I will have a female plant given X seeds?

    Contributed by: The White Rabbit

    Suppose that an experiment can have only 2 possible outcomes. This is known as a Bernoulli trial. In general the outcomes are success or failure.

    If P is the probability of success, and q is the probability of
    failure then p+q=1

    Many Problems can be solved by determining the probability of k
    successes when an experiment consists of n independent Bernoulli trials.
    What we want to know is what is the probability of a success (female) given a certain number of experiments (seeds).

    Probability of k successes in n independent bernoulli trials with
    success as p and failure as q=1-p

    We will use a 50/50 success failure ratio, so p=.5 and q=.5

    Probability of K successes = c(n,k)*p^k* q^(n-k)

    where;
    C(n,k) = n!/r!(n-r)!

    and n! is 'n factorial'.

    for example: 6! = 6*5*4*3*2*1
    : 3! = 3*2*1

    Probability of 1 success w/ 6 seeds is 9.3%
    Probability of 2 success w/ 6 seeds is 23.4%
    Probability of 3 success w/ 6 seeds is 31.25%
    Probability of 4 success w/ 6 seeds is 23.4%
    Probability of 5 success w/ 6 seeds is 9.3%
    Probability of 6 success w/ 6 seeds is 1.563%

    The sum of these gives the probability of getting at least
    1 female from 6 seeds with 50% male female ratio is approx 98%.

    Now it is easier to find this by taking an alternate route. Simply calculate
    the probability of failure. That is the probability of 0 successes and subtracting that from 1.

    i.e. probability of 0 success w/ 6 seeds is 1.563%
    so probability of at least 1 success is 98.43%

    So the final equation we need is:
    1 - C(n,0) * p^0 * q^(n-0)

    SO probability of at least 1 female plant:

    1 seed: 50%
    2 seed: 75%
    3 seed: 87.5%
    4 seed: 93.75%
    5 seed: 96.875%
    6 seed: 98.43%

    This example used a (50/50) male female ratio, but bernoulli trials allow
    insertion of different p's and q's for different male/female
    ratio's like (60/40) or whatnot. just make sure that p+q=1
    in other words the probability of success plus failure = 100%.

    Modification of this concept can answer different questions just use creativity!





    How do I stabilize a clone hybrid?

    Contributed by: ¬§Spiritus†Domini¬§

    where;
    T1 (Hybrid clone) = (t1 x c1)
    T, t, t1, and c1 are all variables of expression.

    1. T1mom x T1male = T1F2
    2. T1 x T1F2 = T1Bx1
    3. T1 x T1Bx1 = T1Bx2
    4. T1 x T1Bx2 = T1Bx3

    5. T1Bx3 x T1Bx3 = T1Bx F2

    6. Choose parents here at the T1BxF2 phase to be used as an out crosser (One may continue down this one more generation if that is chosen), or continue on and cross the selected parents together (Inbreed), make T1BxF3’s, which should be stabilized for whatever application one wishes.

    When selecting offspring, it can be complicated, especially with males, since there is so little to choose from concerning visually.
    I make it a point to label all males, and to grow out their offspring, choosing which offspring is the most potent, and healthy. Also choosing a male for indoors > choose the shortest and healthiest, as well as showing potency in the offspring. As for which traits you are looking for, that is up to the breeder.

    Also note, the original father used in the process above can be from the same hybrid family, but not from the same plant, different sex. If no male of the same is to be found. One would need to find a strain of desired trait/traits, the less genetic load the better. Cross it to the T1 mom, and use the seeds from that, to start the back crossing.

    This is a model formula, and will not guarantee you that the final crosses will be special. It is here to be used to get you where you want the hybrid to be, and what one is trying to stabilize.





    What is a phenotype and what does phenotype mean?

    Contributed by: Chimera

    Phenotype is one of the most incorrectly used terms on marijuana grow forums in my opinion.

    What does phenotype really mean?

    Phenotype is the observable/qualifiable/quantifiable representation of a trait.

    So what does that mean?

    Most folks say there are two main genres, sativa dominant and indica dominant, when actually there is a wide range of leaf phenotypes... the skinny sativa like class, thick indica type class, and many intermediate phenotypes in between the two.

    This can be further compounded by leaves that are pinnate, webbed (ducks foot), curly, pointy tipped, round tipped, single or double serrations etc etc. A quick look in the book MJ botany will show a page of many different leaf phenotypes.

    In this case we are talking about LEAF phenotype. All of these phenotypes can also show purple leaf, or green leaf, The green leafs can be classified as lime green or dark green.. thick leaved, thin leaved (texture).

    Any of these plants may also show purple buds, or green buds... or even red buds.

    See where this is going? There are multiple phenotypes for each and every discernable trait, well more than two. If you examine a pure indica population, you will see variation across the population with respect to many traits.

    We have still only looked at two parts of the plant.... the leaf and the buds.

    The buds can further be broken down into many different characteristics.

    Highly resinous buds vs not quite as resinous. High THC content, or high CBD content. We also have mixed CBD/THC content. This can be further expanded to low overall levels of the primary cannabinoid (THC, CBD, or mixed), or high levels of the primary cannabinoid.

    What about bud density? Dense, airy, or somewhere in between?. Large calyxes or small? Round tipped smaller buds, or long pointy tipped buds? What about large round buds? Small pointy ones? Small airy ones? Large airy ones?

    Smells... fruity, skunky, piney? If fruity, citrus or berry? Citrus? Grapefruit? lemon? Orange? Strawberry? Blueberry? Grape?

    All of these traits can come together in any combination... when we start thinking about which traits are associated, we are actually thinking about something called linkage.

    For example, myself and another breeder have found that orange seems to segregate (appear most often) along with the pointy tipped bud characteristic.

    In order to determine linkage, we have to calculate the frequency of occurrence of these two traits, or phenotypes, in the same plant, over an entire population... the larger the population, the more confident we can be that our conclusions about linkage are accurate.

    So when you see a breeder or seed maker say "I selected the most Thai dominant males", you should ask how did that seed maker determine which were the most "Thai dominant".

    If he says leaf traits, you should laugh!!

    Why?

    Because leaf traits are not known to segregate with the overall positive characteristics of Thai's... there is no assurance that the selection for thin leaves, will in turn guarantee the selection for the uplifting, soaring, STRONG Thai type of high. Get it?

    The only way to select for the Thai high is to cross MANY males to the chosen/desired females, and examine the progeny of each lot individually, in order to determine which male(s) contributed the desired genes.

    If you want my honest opinion.... seed descriptions are a scam. They are advertising tools, and should be looked at as such by the seed buying public. If you notice, many seed makers have started giving "probable outcomes" of plants that they have not grown. A quick look through some of our sponsors shows this in droves.

    Don't be on the lookout for any plant that say have a "grape" flavour, just because the "breeder" says says these are the most potent. The grape one might have been the most potent in the 10 to 15 seedlings he grew (LOL), but overall the grape flavoured one may be less potent on average.

    If a claim is made to look for any phenotype, ask how they came to that conclusion.

    You should only be on the look out for the grape flavour if that is the most important criteria for you.

    If you want the most potent, keep clones of each and after you have harvested only keep the clones from the most potent plants. It just depends on what YOU find important... to me, when growing drug cannabis, I look for drug content.

    OK, so I got off topic a little, but I hope you can see what I was trying to say... there are many possible observable phenotypes for each trait, not just two. It is far more complex than just sativa or indica. Beware of seed makers that make it seem this easy is my advice. If you don't believe me, just grow a couple of packs of any given strain and see the many differences.





    ID #1533
    It appears that one of my plants has both male and female flowers. Is this possible or are plants either male or female?


    Drug varieties of marijuana are generally considered to be dioecious. That is, most individual plants have either male (stamenate) flowers or female (pistillate, carpellate) flowers, but not usually both.
    Fiber varieties of hemp are generally considered to be monoecious. That is, indivudal plants usually have both male and female flowers on the same plant.
    A plant (or any organism that reproduces sexually) that has both male and female sex organs is also known as a hermaphrodite (or "hermie"). Hermaphroditism is a pretty common characteristic in drug varieties of marijuana.
    A plant that has mostly female flowers with a few male flowers can be called a predominantly female hermaphrodite. A plant that has mostly male flowers with a few female flowers can be called a predominantly male hermaphrodite.
    It is widely observed by growers that conditions of stress (such as irregular or increasing photoperiod, light leaks, nute burn, etc.) can cause a (clone of a) predominantly female plant to express hermaphroditism. These plants can be called "hermaphrodite-prone." Strongly dioecious plants that do not express hermaphroditism in response to environmental stresses can be called "hermaphrodite-resistant."
    Some plants will produce male flowers even in near-optimum conditions, these can be called predominantly hermaphroditic.
    The pollen produced by the male flowers may or may not be viable; it might be sterile. However it should be assumed that this pollen is viable, and is capable of pollenating and seeding the rest of the crop.
    The tendency to hermaphoditism is a genetically heritable characteristic; allowing hermaphrodites to reproduce selects for this characteristic. Eliminating hermaphrodites (thus preventing them from reproducing) selects against this characteristic.







    What is tissue culture?

    Tissue culture is a method of propagation using little bits of plant tissue. These bits are seperated from the plant and placed under sterile conditions in an artificial medium. Given the right conditions the cells will continue to grow and divide. Cells in culture don't grow old, but can be kept in this condition indefinately, thus saving valuable space for the breeder. There are two types of tissue culture:
    1. Meristem culture. The meristem is the where the plant is actively growing, and the cells are dividing. The meristem is usually free of viruses and other pathogens, so meristem culture is used to obtain a disease free clone.
    2. Callus culture. The plant tissue is induced to form undifferentiated growth or a callus, then induced to differentiate into the various organs by finding the proper balance of hormones. In meristem culture organs are already differentiated, so epidermal cells give rise to more epidermal cells. In callus culture any cell could become an epidermal cell or any other organ. Auxin is used to promote roots, and cytokinin promotes shoots.





    Should I start my grow from clones or seeds?


    Contributed by: snoofer
    Submitted: 11-10-2003

    Introduction:
    Growers face the decision to start a grow from either seeds or rooted clones. The decision is not obvious, as both growing options have their respective advantages and disadvantages. Growers may have to weigh cost, growing space, crop risk and turn around time.


    [SIZE=+1]Clones[/SIZE]

    Advantages:

    Clones are female! No need to pre-sex or worry about males
    Clones are much faster to veg up and flower than starting from seed, resulting in a quick harvest and a much shorter turnaround time.
    Clones can be quickly grown into moms and re-cloned, for an (almost) instant vegetative and flowering crop
    Clones are genetically identical, but some differences will still be evident in the phenotype. In general, clones will exhibit even growth and growing characteristics.
    Rooted clones can be flowered immediately if space or time is a problem.
    Clones can quickly indicate a strain’s characteristics (smell, vigor, branching pattern, sativa/indica dominance, rooting quality, etc).

    Disadvantages:
    Clones can be difficult to find, as opposed to available seed banks. Clones from unknown sources are of suspect quality and genetics.
    Growers run a high risk of inheriting problems from the last grower: Root rot, spider mites, powdery mildew, etc. If these problems are not identified and treated, they can quickly spread to an entire crop.
    Unhealthy clones may die or remain in shock for an extended period
    Shipped clones may be in shock and take weeks of TLC to recover. There are many stories of medical clones shipped without any protection and arriving flat!
    Clones are more light-sensitive than seeds. Unrooted clones take time to become established, and are easily burned by light (and nutrients)
    As clones are almost always female, breeding options are limited. Hermies are possible with unstable clone crosses.


    [SIZE=+1]Seeds:[/SIZE]

    Advantages
    Seeds obtained from reputable seed banks are of known lineage and genetics. You should have a reasonable idea of what the strain will do in terms of yield, quality and flowering time.
    Breeding and crossing options are possible with male seeds. (Feminized seeds produce a higher % of female seeds, but 100% female is never guaranteed, and hermaphrodites are more possible).
    Hybrid vigor. Females grown from seed are often higher yielding than clones. Strains can lose their vigor over time; growers may want to 'rejuvinate' their grow with the same successful strain.
    Your seeds should produce healthy plants, free of disease and pests.

    Disadvantages:
    Seeds take a long time (and there is more labor, money and time involved) before a harvest can occur.
    Cost. Seeds can be expensive, not only per seed pack, but in the time they take to produce a flowered crop.
    Problems with shipping/customs seizing seed bank deliveries, switched seeds, etc.
    Unstable hybrid strains (See faqs on strain breeding )
    Not all seeds will be viable (germinate) and only 50% of the unfeminized seeds will be female (feminized seeds may produce up to 90% females). Only female seeds will produce female mothers, from which productive clones can be taken and flowered.
    It may take several seed packs to discover an excellent mother.


    The procedure to sex seeds enmasse:

    -germinated
    -grown into mothers
    -clones taken from each mother, labeled, then sexed to tell which mother is female or male
    -the best mothers are selected (males may be optionally discarded).

    -mothers are mass cloned
    -clones are vegetatively grown and then flowered






    Why are F2 seeds less expensive?

    Contributed by: Crazydevs

    Why does one strain cost less from one seed breeder than it does from another?

    Let’s start off by saying that in terms of seed prices, you normally pay for the strain genetics, but this is not always the case, some seed makers (breeders) will always try to charge more on a strain, simply because they seek a larger profit margin than some of their competitors. Also, some breeders have to pay premiums to the original, big name strain breeders, to be able to use the original copyrighted genetics strain name(s).

    It’s also worth noting that just because you have grade A genetics, it does not always mean your going to get top grade plants. Growing conditions and experience can play a much bigger role in a plants end result than the strain genetics.

    So why do some seed makers charge so little in comparison to others? Is something wrong with their genetics?

    No, there is nothing wrong with the genetics. These seeds come from F2 stock, and are sometimes just fast knockoffs of the original strain(s).

    What is F2 stock?

    Ok, I’m not going to go into great depth here on just what an F2 stock of seeds is. Basically, you start of with homozygous strains. These are considered true breeding strains, and will show little variation in phenotype. When you start mixing true breeding strains you end up with heterozygous strains. The phenotypes in these will vary a little more than the homozygous parents. A heterozygous strain is considered to be a hybrid. An F1, F2, F3 etc are all hybrids!

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

    F2 hybrid - is the offspring of a cross between two F1 plants.

    You can also get F1, F2 crosses etc, but I wont go into that.

    Basically, all you need to know is that a seed bank will have a description of a strain and its characteristics. For F1 seed stock, most of the plants will remain true to that description, with little variance. F2 stock will vary more, your get maybe 3-4 plants out of 10 seeds that will be true to the seed bank description, the rest will be a little different.

    So what’s this phenotype about?

    A phenotype is a particular trait or characteristic of a plant. It could be high yield or berry like aroma, but a seed bank will often give you a description of a strain, normally listing the best phenotype. F2 stock phenotypes will vary more than F1 stock. And it gets worse as you progress to F3, F4 etc.

    So basically, when you order an F2 stock of seed, be prepared for lots of different looking plants. However no potency or yield is lost between F1 and F2 plants.

    When ordering F2 stock, the idea is to search out the better phenotypes, and clone them so in future you only work with the best genetics of the bunch. With F1 stock, you should have more uniform plants that all perform similar, and if the breeders done his job correctly, this should be as close to the original description that tempted you to buy the seeds in the first place as you can get!

    So that’s why some breeders charge less for their seeds than others. Remember breeders prices will vary anyway, it’s always worth shopping around for a strain price.






    How do I choose a strain?

    Contributed by: Avis

    Choosing a strain may seem overwhelming at first, but by answering a few simple questions, you will be able to narrow down the choices to strains that suit you best.

    1.) Do you plan on growing INDOORS or OUTDOORS?

    2.) Do you prefer the characteristics of an INDICA (i.e. short, compact, and high yielding)? Do you prefer the characteristics of a SATIVA (i.e. tall, high quality bud, and lower yielding)? Or would you prefer a mix between the two (i.e. 50/50 or 60/40 cross)?

    3.) What type of stone/ high are you looking for? There are two basic types: the first is a ‘body stone’ that knocks you down and holds you there, which is synonymous with INDICAS. A second type of stone is a trippy cerebral high, often associated with SATIVAS.

    How potent do you want it?
    Different strains have their own unique effects (i.e. mellow, happy, paranoid, stupefying, clear and thought provoking, etc, etc…)

    4.) What is your price range? How much are you willing to pay for seeds or clones?

    5.) Is yield important to you? There are low, medium and high yielding cannabis plants. Does yield take precedence over quality?

    6.) Is odor or smell a concern? Stealth growing requires low smelling strains. Some strains smell so strong they may be a security risk.

    Is taste important for you? (Some strains have a unique flavor such as grapefruit, blueberry, etc)

    7.) How long do you want to wait to harvest? Some are 6 week cash-croppers, some will take up to 14 weeks to flower. Many strains take 7-8 weeks.

    8.) The last thing you should do when you have a few strains narrowed down is ask other growers. Find out what growers have experienced with it, etc.








    How do I store seeds?

    For uninterrupted long term storage, freezing in a vacuum pack with a dessicant is best. Each time a batch of seeds goes through a freeze/thaw cycle, a few become unviable. For storage lengths of a few years or less, room temperature storage in an airtight container with a dessicant is satisfactory. Vacuum packing with dessicant and room temperature storage is best for access without the thaw and re-freezing that kills them. The problem with using the refrigerator for any period of time is the excessive amount of moisture constantly present. Each time the door is opened, moisture condenses on items inside, for which the dessicant is an inadequate deterrent for molds. A vacuum sealed container should not condense moisture on the inside. I have no knowledge of the effective lifespan of rice as a dessicant, but it could be replaced occasionally if suspected to be losing effectiveness. Using heat to remove any moisture present in rice or other "makeshift" dessicants will improve effectiveness and longevity. I have heard of vermiculite being used as a dessicant, but would recommend silica gel as a first choice. I heard of properly stored seeds over 10 years old still germinating at acceptable rates.








    The rest of the Overgrow.com FAQ is available Here http://www.growfaq.net
    PanterasSon likes this.
  8.  
    SCARHOLE

    SCARHOLE Well-Known Member

    If any one has any breeding info to add that I have missed please post it up...

    Found this on Ethylene gas an seeds.
    By exposing your seeds to rotting fruit peals the ethylene gas will dramatically increase the female to male ratio.
    An will help greatly promote germination rates, even in very old seeds.



    And ethylene is known to induce an promote germination.
  9.  
    SCARHOLE

    SCARHOLE Well-Known Member

    Have been watching a journal where a guy germed 9 out of 11 25+ year old columbian seeds with banana ethylene.

    His last batch had the same germ rates an 18 out of 20 were fems.

    I believe there is something to this an plan to use it on all reg seeds...
  10.  
    little butch

    little butch Active Member

    A question to the gods of the breeding thread. I am a medical stealth grower. I have the usual odor controls in place (carbon scrubber,ona gel, etc. I know I am only one of millions who worry about odor, and I have spent a significant sum (for me). My question to you breeders is from someone who has only done breeding accidently. So my first point is that, unless you are legal or stupid, you would be nuts not to worry about odor with your grow. Soooooo.......realizing that I am at your mercy, and have no knowledge of the subject of breeding, I beg you to correct my ignorance, because that's what it is. If most growers are concerned about odor, Would it not be a cool idea to breed traits, like the reasonably odor neutral blue mystic trait to the stinkiest (dankest) weed varietys.and thus save millions of people lots of cash on odor measures by reducing the odors from the plants to more managable levels. I know that, I for one would be humbled by your greatness and be on board to pay a few more bucks for my seeds if they weren't so stinky for my stealth grow. And now my greatest dream is that a breeding expert would be starting on my little project by sometime tomorrow.... Sooooooooo........who's volunteering ????????? I honestly think that whoever could be the first to conquer the odor problem with genetics instead of chemicals, would almost be the new savior of the cannabis community. Might even make a few bucks along the way to fame.... I honestly know that it would be a monumental project, and extremely long lasting and tedious. It could also turn a young smart guy in to someone who's name was somewhere in the minds of 2 billion ?? cannabis smokers. How about it??? Anyone out there who wants to be famous ???
  11.  
    SCARHOLE

    SCARHOLE Well-Known Member



    Faldikar likes this.
  12.  
    |B3RNY|

    |B3RNY| Active Member

    This should be kept up, especially if anyone is to set some standards for the entire industry (which would eliminate massive confusion.)
    Standards need to be set in almost all areas of the industry, in breeding, naming, definitions, etc. We need the industry to become "truebreeding for all traits", instead we have an industry that throws many variables. Lol.
  13.  
    trouble27

    trouble27 Active Member

    lol i need that book can u guys suggest good reading material besides the reffrance material u have listed for someone looking to experiment with breeding appreciate it thanks in advance.
  14.  
    greenstar420

    greenstar420 Member

    Great info here!
  15.  
    polyarcturus

    polyarcturus Well-Known Member

    amazing thread a wealth of good info +rep

    only thing i see missing is a few of the obscure facts ive learned from breeding,

    1) all female cannabis plant have the ability to be hermaphrodite.

    2) sex is genetically
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    determined, as mentioned some hermaphrodites have a tendency to produce only male flowers, all males should be grow as long as possible to see development o female flowers, thus confirming a female, also stress test you males, if you can force female flowers from a true male this means you have a rare mutation similar to what a tripoloidy is.(extra chromosome) ethylene ensures that a hermaphrodite that would have been a predominantly male plant, grows more feminine, there are other environmental variables that also play into this(light spectrum, nutrition, ect)

    3) pollen can be stored a couple months in the refrigerator, even longer in the freezer. but note, if stored in freezer, place in fridge first when thawing too quickly condensation will ruin viability.
  16.  
    crimsonfro911

    crimsonfro911 Active Member

    i prolly just clicked on about 100 of these. lol

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