schrooomy420
01-07-2008, 12:39 AM
I found an old disk from before I ripped out my old hard drive and left the country for a year. I was chatting with Green Supreme over at www.fullmeltbubble.com and told him I would stick it up over here. There is a bunch of usefull info in there, but yes it is VERY long. But hey what do you want old Brothers Grim and Vic High info, good score I think. Peace
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 – The female cannabis plant, unlike the male, is grown to produce marijuana. Premium marijuana is produced in seedless form by eliminating all pollen sources from the growing environment. Seed production reduces the value of marijuana dramatically by lowering the yield and potency of the flowers. Hermaphrodites are plants expressing both male and female flowers. They may fool a grower who mistakes the "hermie" for a female - only to find his crop is ruined by the unexpected release of pollen. Knowledgeable marijuana breeders are very careful to avoid hermaphrodism in their seedlines.
The attributes of a valuable female are the following (in descending order of importance):
1. Resistance to hermaphrodism
2. Vigor/Yield
3. Potency
4. Flavor
5. Rate of flowering response
6. Resin production
7. Stature
8. Scent
9. Floral structure
10. Floral color
Male Cannabis – The male cannabis plant is essentially only useful for breeding. The male plant makes very poor marijuana, being mostly leaves without the dense resinous floral clusters of the female the yield is miserable. More importantly, the male of the species has virtually no potency in comparison to that of female cannabis. The males do carry genes that influence the expression of ALL the traits listed above, but not many of them are directly observable in the male itself due to the male phenotype being markedly different from the female phenotype. A male cannabis plant’s value is DEFINED by the quality of his daughters.
Naturally, when starting out with a large number of potential breeding individuals, one desires to “weed out” the undesirable individuals.
The female is easy to evaluate because all the traits favoring marijuana production are directly observable in the female. It's a simple matter of growing & flowering the females to grade their performance and smoking the resulting marijuana. The breeder then chooses only those females most closely matching the breeder's personal ideal to be used as seed parents.
The directly observable & important traits of male cannabis are as follows:
1. Resistance to hermaphrodism
2. Vigor
3. Stature
4. Maturation rate
All males expressing poor quality in any of these traits should be culled so as not to pass the weak trait on to the progeny.
Males are also be observed to have a certain scent and floral structure but the importance of these traits pale in comparison to those listed.
The potency of male plants, and especially the potency difference between individual males in a group, is generally too subtle to be measured by anything short of professional scientific laboratory equipment. Moreover, there is no conclusive proof that the most potent male in a group actually creates the most potent female progeny, although it seems intuitive that that should be the case. The difficulty of determining a male plant's potency is a major hurdle to proving this link.
Thankfully, logic dictates that the potency of a male plant ITSELF isn’t very important, as we aren’t interested in growing males for marijuana production. The value of a male lies entirely in the traits he consistently passes on to his daughters. Therefore it’s unnecessary to identify the one male amongst a group of potential pollen donors with the greatest potency. It’s far more logical to evaluate the female progeny of each male to define the potency of each male in the group.
Male cannabis individuals may be graded for quality by a controlled pollination of IDENTICAL female clones (one for each pollen donor). This isolates the influence of the male by holding CONSTANT the influence of the female on each cross. The seeds resulting from each clone are then grown and the progeny is graded to determine which of the crosses was the most successful. When the group with the most desirable female progeny is identified, the responsible male has been identified as the most valuable. Males can be kept in the vegetative state exactly like female “mother plants”, except that we should call them “dads” of course. Clones from the favored male can be flowered as needed along with the breeding female(s) when seeds are desired.
Due to the clandestine nature of marijuana growing, in most cases there will only be about 10 males to be evaluated after culling all those with directly observable defects. Breeding with larger populations is always preferable, as genetics is a statistical "game".
Commercial breeders would clearly benefit from the development of a reliable method of identifying males with the greatest potential for passing on high potency genes. Perhaps someone will do the necessary research someday, but by following the above method, growers can accurately pin-point the ONE male in their small group which is the most potent...in the only meaningful sense of “male potency”.
What are all female seeds and how are they created?
Added by: ~shabang~ Last edited by: ~shabang~ Viewed: 2178 times
Contributed by Mr.XX and TheSiliconMagician:
This is the strategy of Mr. XX, a Dutch breeder, for creating all female seedlines from slight hermaphroditic pollen. What he does is put the lights on 12/12 for 10 days. Then turns the lights on 24 hours, then 12/12 again for a few days, then back to 24 hours for a day, then 12/12 again for a few weeks.
If he does this and no hermaphrodites come up. He has found a 100% XX female that cannot go hermaprhoditic naturally. He says that your chances of finding a 100% XX female is vastly increased when using Indica genetics. He told me that the more Afghanni or Nepalese genetics the plant has, the better the chances of finding a natural XX female. His
exact words were "Where did mother nature give weed a home at originally?"
I tried to get him to narrow it down to a ratio, but he never specified just how many plants per are XX females his exact words are "plenty of XX girls for everybody" and that is all he will say on the subject. Only that it takes alot of time and alot of plants to find that one female.
He then uses Gibrellic acid. 30 centiliters of water with 0.02 grams of Gibrellic acid and 2 drops of Natruim Hydroxide to liquify the Gibrellic. Then applies as normal and creates the male flowers. He has gotten down to the 4th Generation with NO loss of vigor, NO genetic deficiencies and NO hermaphrodites. He claims that the plants are EXACT GENETIC CLONES of one another. Complete sisters. Basically it's clone from seed instead of from normal cloning methods.
How do I create a true breeding strain?
Added by: ~shabang~ Viewed: 1869 times
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
How do I backcross my special female?
Added by: ~shabang~ Last edited by: ~shabang~ Viewed: 1637 times
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).
.
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 – The female cannabis plant, unlike the male, is grown to produce marijuana. Premium marijuana is produced in seedless form by eliminating all pollen sources from the growing environment. Seed production reduces the value of marijuana dramatically by lowering the yield and potency of the flowers. Hermaphrodites are plants expressing both male and female flowers. They may fool a grower who mistakes the "hermie" for a female - only to find his crop is ruined by the unexpected release of pollen. Knowledgeable marijuana breeders are very careful to avoid hermaphrodism in their seedlines.
The attributes of a valuable female are the following (in descending order of importance):
1. Resistance to hermaphrodism
2. Vigor/Yield
3. Potency
4. Flavor
5. Rate of flowering response
6. Resin production
7. Stature
8. Scent
9. Floral structure
10. Floral color
Male Cannabis – The male cannabis plant is essentially only useful for breeding. The male plant makes very poor marijuana, being mostly leaves without the dense resinous floral clusters of the female the yield is miserable. More importantly, the male of the species has virtually no potency in comparison to that of female cannabis. The males do carry genes that influence the expression of ALL the traits listed above, but not many of them are directly observable in the male itself due to the male phenotype being markedly different from the female phenotype. A male cannabis plant’s value is DEFINED by the quality of his daughters.
Naturally, when starting out with a large number of potential breeding individuals, one desires to “weed out” the undesirable individuals.
The female is easy to evaluate because all the traits favoring marijuana production are directly observable in the female. It's a simple matter of growing & flowering the females to grade their performance and smoking the resulting marijuana. The breeder then chooses only those females most closely matching the breeder's personal ideal to be used as seed parents.
The directly observable & important traits of male cannabis are as follows:
1. Resistance to hermaphrodism
2. Vigor
3. Stature
4. Maturation rate
All males expressing poor quality in any of these traits should be culled so as not to pass the weak trait on to the progeny.
Males are also be observed to have a certain scent and floral structure but the importance of these traits pale in comparison to those listed.
The potency of male plants, and especially the potency difference between individual males in a group, is generally too subtle to be measured by anything short of professional scientific laboratory equipment. Moreover, there is no conclusive proof that the most potent male in a group actually creates the most potent female progeny, although it seems intuitive that that should be the case. The difficulty of determining a male plant's potency is a major hurdle to proving this link.
Thankfully, logic dictates that the potency of a male plant ITSELF isn’t very important, as we aren’t interested in growing males for marijuana production. The value of a male lies entirely in the traits he consistently passes on to his daughters. Therefore it’s unnecessary to identify the one male amongst a group of potential pollen donors with the greatest potency. It’s far more logical to evaluate the female progeny of each male to define the potency of each male in the group.
Male cannabis individuals may be graded for quality by a controlled pollination of IDENTICAL female clones (one for each pollen donor). This isolates the influence of the male by holding CONSTANT the influence of the female on each cross. The seeds resulting from each clone are then grown and the progeny is graded to determine which of the crosses was the most successful. When the group with the most desirable female progeny is identified, the responsible male has been identified as the most valuable. Males can be kept in the vegetative state exactly like female “mother plants”, except that we should call them “dads” of course. Clones from the favored male can be flowered as needed along with the breeding female(s) when seeds are desired.
Due to the clandestine nature of marijuana growing, in most cases there will only be about 10 males to be evaluated after culling all those with directly observable defects. Breeding with larger populations is always preferable, as genetics is a statistical "game".
Commercial breeders would clearly benefit from the development of a reliable method of identifying males with the greatest potential for passing on high potency genes. Perhaps someone will do the necessary research someday, but by following the above method, growers can accurately pin-point the ONE male in their small group which is the most potent...in the only meaningful sense of “male potency”.
What are all female seeds and how are they created?
Added by: ~shabang~ Last edited by: ~shabang~ Viewed: 2178 times
Contributed by Mr.XX and TheSiliconMagician:
This is the strategy of Mr. XX, a Dutch breeder, for creating all female seedlines from slight hermaphroditic pollen. What he does is put the lights on 12/12 for 10 days. Then turns the lights on 24 hours, then 12/12 again for a few days, then back to 24 hours for a day, then 12/12 again for a few weeks.
If he does this and no hermaphrodites come up. He has found a 100% XX female that cannot go hermaprhoditic naturally. He says that your chances of finding a 100% XX female is vastly increased when using Indica genetics. He told me that the more Afghanni or Nepalese genetics the plant has, the better the chances of finding a natural XX female. His
exact words were "Where did mother nature give weed a home at originally?"
I tried to get him to narrow it down to a ratio, but he never specified just how many plants per are XX females his exact words are "plenty of XX girls for everybody" and that is all he will say on the subject. Only that it takes alot of time and alot of plants to find that one female.
He then uses Gibrellic acid. 30 centiliters of water with 0.02 grams of Gibrellic acid and 2 drops of Natruim Hydroxide to liquify the Gibrellic. Then applies as normal and creates the male flowers. He has gotten down to the 4th Generation with NO loss of vigor, NO genetic deficiencies and NO hermaphrodites. He claims that the plants are EXACT GENETIC CLONES of one another. Complete sisters. Basically it's clone from seed instead of from normal cloning methods.
How do I create a true breeding strain?
Added by: ~shabang~ Viewed: 1869 times
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
How do I backcross my special female?
Added by: ~shabang~ Last edited by: ~shabang~ Viewed: 1637 times
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).
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