When is a crossbred strain considered stable??

"A common technique to stabilize a cannabis strain is called "cubing", in which the breeder will seek specific traits in the hybrid offspring (e.g. greater resin production, tighter node spacing, etc.) and breed said offspring with a parent plant. The same traits are sought in the new inbred offspring, which are then again bred with the original parent plant. This process is called cubing because it usually repeated across three (or possibly more) generations before a strain can be considered at least somewhat stable." - Taken from Wikipedia.org


So how many times would you guys say you should cube a cross before its considered stable???

i belive any more than three is a waste from my pollen chucking ... plants get more finiky after that ....like you screwing your sis and her her doin the kid and so forth... but fully cubing somthing like as in cindy 99 you can lock down good traits if you search from large gene pools and know what your looking for ... dj short has alot of info on this.... he belives rudealis is from breeders in the 70's breeding for speed over and over eventually making auto flower... he called it a dark art crossing just for speed not other char..

that is intresting

So what is the exact process say I wanted to cloan a Ak48 with a wonder woman ? How would I do so to create a new x strain . woah how cool would it be to have your own strain.

Joedank said:

dj short has alot of info on this.... he belives rudealis is from breeders in the 70's breeding for speed over and over eventually making auto flower... he called it a dark art crossing just for speed not other char..

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According to High Times the first documented experiments in crossing drug strain varieties with their Ruderalis cousins were performed by Ernest Small of Agriculture Canada in Ontario during the 1970's, for the aiding in the
purposes of taxonomic classification. But if DJ Short is saying "he belives rudealis is from breeders in the 70's," as in that was when Ruderalis was first discovered, or was created, that would be wrong. The first known documentation of Ruderalis that I am aware of occurred in 1924 by a Russian student I have only known by the name of Janischevsky.

If DJ Short believes Ruderalis was first introduced into cannabis breeding by man in the 70's he might be correct. But then who knows what sort of undocumented breeding occurred prior to the discovery of Ruderalis in 1924 and also between 1924 and the 1970's?

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

So after three backcrosses the strain will be pretty stable. thanks guys.

I would say 4 back crosses to stabilize them.

Brick Top said:

If DJ Short believes Ruderalis was first introduced into cannabis breeding by man in the 70's he might be correct. But then who knows what sort of undocumented breeding occurred prior to the discovery of Ruderalis in 1924 and also between 1924 and the 1970's?

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From what I found, DJ Short does believe that the Ruderalis exists, while also believing that a day neutral photoperiod is obtainable through breeding.

I was really hoping to find an article claiming some sorta Russian Coverup to keep us from knowing the truth about some american marijuana breeding conspiracy.

Ruderalis: myth and misnomer

As indoor growers attempted to improve their genetic lines via breeding, another interesting phenomenon occurred: Ruderalis. Although there is a wild variety identified as Ruderalis in Russia ("Ruderalis" is supposedly Russian for "by the side of the road") that grows very short and matures very fast, I seriously doubt the rumor that someone actually went to Russia to collect seeds of this variety sometime in the past. Or, if someone actually did go all the way to Russia to find, collect and smuggle "rudy" seeds, I do feel sorry for their waste of time. They could have gotten the same worthless thing from Minnesota, Saskatchewan or Manitoba with much less hassle.

The North American Ruderalis probably originated as follows: After the Indica varieties arrived in the US and became incorporated into the gene pool, many breeders began to cross the earliest maturing individuals with each other in hopes of shortening the maturation cycle.

It would only take a few generations for the ugly Rudy phenotypes to begin expressing themselves. By ugly, I am referring to a strong lack of potency and/or desirability. I know, I was once guilty of the practice myself. It did not take me long to realize that this was a huge mistake in regard to the quality and potency of the future generations' finished product, and all subsequent breeding along this line was ceased.

Many of these manipulated rudies were released on the open market between 1981 and 1986. It was shortly after this period that the grow journals of the era (Sinsemilla Tips and High Times) ran articles about the possibility of a new wonder variety for indoor grows: fast blooming Ruderalis. Rumor had spread to myth and misnomer. Therefore, it may be more appropriate to say that the Ruderalis phenotype was coaxed from Indica genetics, via the indoor breeding environment.

The same applies to many of the Indica dominant varieties available today. Breeders selecting for early, fast flowering or fast growth often miss out on some of the finer and more subtle characteristics available from crossing certain genotypes. My advice to breeders is to wait until the finished product is suitably tested before coming to any conclusions regarding desirable candidates for future breeding consideration.

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In the experiment to breed Orange Skunk i crossed [Male Purple orange velvet pheno] Jillybean X Tangerine funk f1(male Orange smelling pheno TGA-Agent orange X Garlic citrus skunk female pheno Sensi-Shiva skunk) then took that gen of (JB X TF f1) female crossed it with the same orange velvet Jillybean male i have and i now got a stable sweet orange skunk that purples alot during flower when outdoors and slightly indoors, tinges of purple to black on the buds.. i have Citrus skunk, similar parentage instead of Jillybean male as the parent i used male Gage Green-Grape Stomper i got to snag off a friend. has a lemony orange and berry taste, serious citrus Terpenes odor is straight citrus salad.

I agree with chimera on this guys
And thanks closetsafe for looking up the real quote I often wonder if peeps take it seriously that I know this shit without quotes... But here's one to back me up posted by another here not long ago
Originally Posted by shepj
All right guys, obviously I didn't write this, but I think it's something interesting and definitely helpful for breeding.

Cubing.......a myth.

Here's breeder chimera's take on the subject:

"you’ve just discovered the biggest myth (IMNSHO) of marijuana breeding- it is a mistake that almost EVERYONE makes (including many of the most respected breeders!).

Backcrossing will not stabilize a strain at all- it is a technique that SHOULD be used to reinforce or stabilize a particular trait, but not all of them.

For e.g.- G13 is a clone, which I would bet my life on is not true breeding for every, or even most traits- this means that it is heterozygous for these traits- it has two alleles (different versions of a gene). No matter how many times you backcross to it, it will always donate either of the two alleles to the offspring. This problem can be compounded by the fact that the original male used in the cross (in this case hashplant) may have donated a third allele to the pool- kinda makes things even more difficult!

So what does backcrossing do?
It creates a population that has a great deal of the same genes as the mother clone. From this population, if enough plants are grown, individuals can be chosen that have all the same traits as the mother, for use in creating offspring that are similar (the same maybe) as the original clone.
Another problem that can arise is this- there are three possibilities for the expression of a monogenic (controlled by one gene pair) trait.

We have dominant, recessive, and co-dominant conditions.

In the dominant condition, genotypically AA or Aa, the plants of these genotypes will look the same (will have the same phenotype, for that trait).

Recessive- aa will have a phenotype

Co-dominant- Aa- these plants will look different from the AA and the aa.

A perfect example of this is the AB blood types in humans:

Type A blood is either AA or AO
Type B blood is either BB or BO
Type AB blood is ONLY AB
Type O blood is OO.

In this case there are three alleles (notated A, B, and O respectively).

If the clone has a trait controlled by a co-dominant relationship- i.e. the clone is Aa (AB in the blood example) we will never have ALL plants showing the trait- here is why:

Suppose the clone mother is Aa- the simplest possibility is that the dad used contributes one of his alleles,
let us say A. That mean the boy being use for the first backcross is either AA or Aa. We therefore have two possibilities:

1) If he is AA- we have AA X Aa- 50% of the offspring are AA, 50% are Aa. (you can do the punnett square to prove this to yourself).

In this case only 50% of the offspring show the desired phenotype (Aa genotype)!

2) If the boy being used is Aa- we have Aa X Aa (again do the punnett square) this gives a typical F2 type segregation- 25% AA, 50% Aa, and 25% aa.
This shows that a co-dominant trait can ONLY have 50% of the offspring showing the desired trait (Aa genotype) in a backcross.

If the phenotype is controlled by a dominant condition- see example #1- all 100% show the desired phenotype, but only 50% will breed true for it.

If the phenotype is controlled by a recessive condition- see example #2- only 25% will show the desired phenotype, however if used for breeding these will all breed true if mated to another aa individual.

Now- if the original dad (hashplant) donates an 'a' allele, we only have the possibilities that the offspring, from which the backcross boy will be chosen, will be either Aa or aa.
For the Aa boy, see #2.
For the aa boy (an example of a test cross, aa X Aa) we will have:
50% aa offspring (desired phenotype), and 50% Aa offspring.

Do you see what is happening here? Using this method of crossing to an Aa clone mother, we can NEVER have ALL the offspring showing the desired phenotype! Never! Never ever ever! Never!! LOL

The ONLY WAY to have all the offspring show a Aa phenotype is to cross an AA individual with an aa individual- all of the offspring from this union will be the desired phenotype, with an Aa genotype.

Now, all of that was for a Aa genotype for the desired phenotype. It isn't this complicated if the trait is AA or aa. I hope this causes every one to re-evaluate the importance of multiple backcrosses- it just doesn't work to stabilize the trait!

Also- that was all for a monogenic trait! What if the trait is controlled by a polygenic interaction or an epistatic interaction- it gets EVEN MORE complicated? AARRGH!!!!

Really, there is no need to do more than 1 backcross. From this one single backcross, as long as we know what we are doing, and grow out enough plants to find the right genotypes, we can succeed at the goal of eventually stabilizing most, if not all of the desired traits.

The confusion arises because we don't think about the underlying biological causes of these situations- to really understand this; we all need to understand meiosis.

We think of math-e.g. 50% G13, 50% hashplant

Next generation 50% G13 x 50% g13hp or (25% G13, 25%HP)

We interpret this as an additive property:
50% G13 + 25% G13 +25% HP = 75% G13 and 25% hashplant

This is unfortunately completely false- the same theory will apply for the so called 87.%% G13 12.5% HP next generation, and the following 93.25% G13, 6.25% HP generation; we'd like it to be true as it would make stabilizing traits fairly simple, but it JUST DOESN'T work that way. The above is based on a mathematical model, which seems to make sense- but it doesn't- we ignore the biological foundation that is really at play.

I hope this was clear, I know it can get confusing, and I may not have explained it well enough- sorry if that is the case, I'll try to clear up any questions or mistakes I may have made.

Have fun everyone while making your truebreeding varieties, but just remember that cubing (successive backcrosses) is not the way to do it!

-Chimera"