-==GROW FAQ SUBMISSIONS==-

[00420]

What are all female seeds and how are they created?

What are all female seeds and how are they created?

GrowFAQ : Breeding : Breeding strategies

What are all female seeds and how are they created?
Added by: administrator
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.

 

[00420]

How do I backcross my special female?

How do I backcross my special female?

GrowFAQ : Breeding : Breeding strategies

How do I backcross my special female?
Added by: administrator
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.

 

[Guest]

***Another Idea***

is there any way for admin or mods to type a "Keyword" that would trigger movement of a thread to an "archive area" ? (i know there is just not sure how so can't enlighten yas)

on another site i was on a while back when a member did a write up in a thread of it's own, and it was something that admin wanted to keep for posterity in the FAQ, they would come into the thread and type:

"ARCHIVE MATERIAL"

and it would send a copy of the thread to whichever area of the "FAQ-Closed Forum" was appropriate.

...a thought.

see: www.mycotopia.net 's "Vaults" for more info. on this idea.... their archive/vault is put together in this manner.

 

[00420]

How do I stabilize a clone hybrid?

How do I stabilize a clone hybrid?

GrowFAQ : Breeding : Breeding strategies

How do I stabilize a clone hybrid?
Added by: snoofer
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.

 

[00420]

What are all female seeds and how are they created?

What are all female seeds and how are they created?

GrowFAQ : Breeding : Breeding strategies

What are all female seeds and how are they created?
Added by: administrator
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.

 

[00420]

How do I create a true breeding strain?

How do I create a true breeding strain?

GrowFAQ : Breeding : Breeding strategies

How do I create a true breeding strain?
Added by: administrator
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

 

[00420]

Can I breed effectively indoors?

Can I breed effectively indoors?

GrowFAQ : Breeding

Can I breed effectively indoors?
Added by: MR_NATURAL420
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.

 

[Guest]

CHILLLLLLLLLLL! LOL!

how to stabaliZe a clone-hybrid LMAO

thats a bit advanced for the noobs lookin for info on how close to keep the flourescent bulb to their seedlings

fuckin awesome info tho, i'll be readin this thread over later on for my own friggin reference!!
LOL!

tons of great info dublO, just don't kill yourself with the intricate, more advanced teks, and try to stick with the basics (i know, it's tough) thanks so much dude, you are an asset to the community, a gentleman and a scholar, a pimp and a playa...

 

[00420]

Kryptonite's pollination method

Kryptonite's pollination method

GrowFAQ : Breeding : Pollination

Kryptonite's pollination method
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!!!!

 

[00420]

How long can I store pollen?

How long can I store pollen?

GrowFAQ : Breeding : Pollination

How long can I store pollen?
Added by: Team GrowFAQ
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.

 

[00420]

Lucas' pollination method

Lucas' pollination method

GrowFAQ : Breeding : Pollination

Lucas' pollination method
Added by: Bongaloid
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.

 

[00420]

How do I pollinate?

How do I pollinate?

GrowFAQ : Breeding : Pollination

How do I pollinate?
Added by: Team GrowFAQ Last edited by: Bongaloid
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.

 

[00420]

How do I select for combining ability?

How do I select for combining ability?

GrowFAQ : Breeding : Hybrid vigour

How do I select for combining ability?
Added by: MR_NATURAL420
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.

 

[00420]

What is selfing?

What is selfing?

GrowFAQ : Breeding : Breeding strategies

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.

 

[00420]

What are the different types of crosses?

What are the different types of crosses?

GrowFAQ : Breeding : Breeding strategies

What are the different types of crosses?
Added by: MR_NATURAL420
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.

 

[00420]

What are gametes and zygotes?

What are gametes and zygotes?

GrowFAQ : Breeding

What are gametes and zygotes?
Added by: MR_NATURAL420
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.

 

[00420]

Soul's Selecting breeding individuals for marijuana production

Soul's Selecting breeding individuals for marijuana production

GrowFAQ : Breeding : Breeding strategies

Soul's Selecting breeding individuals for marijuana production
Added by: Bongaloid
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”.

 

[00420]

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

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

GrowFAQ : Breeding


Added by: snoofer
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!

 

[00420]

What is the difference between an F1 and a hybrid?

What is the difference between an F1 and a hybrid?

GrowFAQ : Breeding

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

 

[00420]

What is an F1, F2, and IBL?

What is an F1, F2, and IBL?

GrowFAQ : Breeding

Added by: MisterIto
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.