Reversed Backcrossing:)

[Colina]

Mostly,it causes a mess.

The long way around can be taken, and still end up with the same damn mess.

Genotype testing via selfing can take out a whole lot of guess work. Think about the implications for a moment.

Gather all of your OG Kush's, your Chem's, your diesel's, self them all, observe the progeny and quickly determine which are likely the best candidates for more time consuming backcrossing programs. As well as which are likely the best candidates for outcrossing.

 

[GMT]

surely if you did that successfully in both lines, then you would have the same genetic makeup in both lines, and therefore crossing the 2 lines would be the same as crossing within a line. Either way, I wouldn't consider it to be an outcross.

 

[Colina]

It's a matter of degree guys. Breeding a dog of X breed from EU with a dog of the same breed from USA that are far removed in pedigree will bring more vigor than breeding full-sibs from down the street, but not as much vigor as the outcross. Selfing by the way removes parallel lines more quickly from each other than full sib mating.

 

[McSnappler]

http://www.scribd.com/doc/14571756/The-Biotechnology-of-Cannabis-Sativa
the bio technology of cannabis sativa

There's a great paragraph on page 14, perfect for this thread..

As stated by Albert Einstein, imagination can be more powerful than knowledge. However imagination is cultivated more easily through concepts of knowledge, making both imagination and knowledge necessary for maximum progress.

 

[englishrick]

It's a matter of degree guys. Breeding a dog of X breed from EU with a dog of the same breed from USA that are far removed in pedigree will bring more vigor than breeding full sibs from down the street, but not as much vigor as the outcross. Selfing by the way removes parallel lines more quickly from each other than full sib mating.

Hay GMT....when col says "Selfing removes parralell lines more quickly"...

i believe he is talking about how SELFING actualy creates IBL`s mutch faster than M/F breeding...he allso seems to support the understanding that 2 inderpendant f IBL`s can be created from f1 seeds all from the same stock too,,,

even identical IBL`s can geneticly differ over generations in a inderpendant localized population,,,,an "in time" crossing the 2 will creates hybrid vigor

so,,,, if i seperate the f1 seeds into 2 batches,,,, an i make 2 inderpendant IBL f lines from my f1 seeds,,, eventualy i could "outcross" the 2 f IBL to create vigor,,,,,,,,,

is this all correct?

 

[englishrick]

The long way around can be taken, and still end up with the same mess.

Genotype testing via selfing can take out a whole lot of guess work. Think about the implications for a moment.

Gather all of your OG Kush's, your Chem's, your diesel's, self them all, observe the progeny and quickly determine which are the best candidates for more time consuming backcrossing programs.

wft just happend

 

[GMT]

I disagree. If you were to merely inbreed them, or self them repeatedly, then that would be the case due to genetic drift, however if you are backcrossing both lines to the original P1 parent at each generation, then this drift will be countered. Colina is discussing theory rather than the practice that you are proposing to engage in. For instance, I recently sent a little package of seeds to someone in the usa, now if they inbreed them for multiple generations, while I do the same here, if in several years we then bred the offspring together, then we may get a boost to vigour, if we selfed them at each generation (and no negative effects came of that) and then bred them together then what Colina says is that we would see more of a boost to vigour. If we however outcrossed them to something like haze, then we would get the highest boost to vigour. Which is why he started it off by saying that we are talking about degrees.

 

[englishrick]

i believe,,,,as soon as you "self" an indervidual you are actualy makin a new line,,,

if you seperate the f seeds into 2 batches,,,,and then you self 1 indervidual from each batch,,,, the 2 lines are now comleetly inderpendant,,,and the 2 will evolve totaly differently,,,this is why you will see the vigor when they are crossed

 

[cork144]

i believe,,,,as soon as you "self" an indervidual you are actualy makin a new line,,,

if you seperate the f seeds into 2 batches,,,,and then you self 1 indervidual from each batch,,,, the 2 lines are now comleetly inderpendant,,,and the 2 will evolve totaly differently,,,this is why you will see the vigor when they are crossed

i would say thats true after afew generations, untill the 2 lines become very distinct through different selections.

 

[GMT]

what is it that you are looking to achieve? What is your end goal in all this?

 

[Colina]

Rick,

They are not completely independent, nor will they evolve totally differently. You will not see anywhere near the return of fitness that the outcross will bring.

 

[englishrick]

but it will increese some fitness,,,,,no?

this must mean they are different,,,,,no?

 

[englishrick]

removed might be a better word than different,,,,

similar topology but not identical topology.....no?

 

[cork144]

Rick,

They are not completely independent, nor will they evolve totally differently. You will not see anywhere near the return of fitness that the outcross will bring.

yea makes perfect sence to me, unless the female selection is absolutely spot on then i would imagine it could compare.

Basicly with what ive learnt from the great posts that have been on this thread, is outcrossing then going to f3 on the produced seeds, then bx, , allthough i am determined to outcross to 2 different strains and make 2 entirely different ibls, then cross the 2.

 

[Colina]

Yes Rick.

Shull did some experiments. Crossing full-sibs from within a selfed line showed little improvement over selfing, but the difference increased as the number of gens increased. Removed parallel lines from within the same family must surely show more improvement. But all this must surely pale in comparison to the fitness restored via outcrossing.

 

[englishrick]

what if we make loads of f IBL lines from the 1 indervidual ...then we keep crossing to "removed" parralell lines....its gona be ristoring vigor every time.....no?

 

[GMT]

My last post before bed, Rick you are aware that the road that youre about to go down is going to take you a number of years arent you not months.

 

[englishrick]

selfing is supposed to be the quickest route to IBL....no?

 

[Weedninja]

what is it that you are looking to achieve? What is your end goal in all this?

Exactly! Most of the responses to this project have been based on an eventual outcrossing.

 

[englishrick]

this was 1 of my first concepts for this project....

it incorperates a male to use as the main outcross,,,,,the way in witch i incorperate it makes no difference,,,,,im improving my ideas for this all the time

the main point is:,,,,,,,i cross 2 f IBL`s on the left side of the diagram,,,,and i also cross 2 f IBL`s on the right side of the diagram,,,,then i incorperate the male,,"i.e. the main outcross"

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