Backcrossing ? Why ?

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GT21

GT21

I like soup
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I have read when one must back-cross 3 to 4 times to achieve a true strain ? need information about - to help understand Guess breeding is the next level
Its called bottle necking ... say you start with a bunch of different phenos.. in nature it could be a earthquake or flood that kills off the undesirables... or through human intervention you control the genetics to your liking. Usually by 3 you have a pretty tight cross. I have seen people bang plants a first time and get tight genetics though.
 
xavier7995

xavier7995

Backcrossing should result in the offspring having a higher frequency of the desired genes, each successive bx increasing that frequency. So you have your rad plant that is a super awesome pheno. That gets a normal cross to another plant, giving you a 50/50 split of genes in theory. From those offspring you find the one that has the traits closest to your original rad plant and then cross back to the original. Grow out those, select plants, cross back to parent and so on. Each generation of seeds should result in plants closer to the original.

Hope that helps.
 
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C

CBF

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Depending on the line your ideal plant was sourced from, you could see inbred depression fairly fast.

IMO a backcross is a tool used while doing filial generations, instill more of your selected plants traits as you continue to reach your homozygous population.

Nothing worse then a batch of retarded plants:)
 
T

ToTHC

Backcrossing should result in the offspring having a higher frequency of the desired genes, each successive bx increasing that frequency. So you have your rad plant that is a super awesome pheno. That gets a normal cross to another plant, giving you a 50/50 split of genes in theory. From those offspring you find the one that has the traits closest to your original rad plant and then cross back to the original. Grow out those, select plants, cross back to parent and so on. Each generation of seeds should result in plants closer to the original.

Hope that helps.
Really good description man. Obviously the selection aspect made sense but I never fully got what people meant by back crossing and always assumed when breeding the plants out you would select a male and female from the second generation that had the desired traits and then from the third generation and so on. This is obviously a much more practical way to get the exact traits you want.
 
masshole61

masshole61

Makes you appreciate the time that breeders put in to make stable genetics. Not shitting on the pollen chuckers of the world, but when you buy a pack of beans, and they all generally have similar growth patterns, someone put the work in. Much respect to all breeders.
 
Buzzer777

Buzzer777

Figured I would attach this to an old thread instead of making a new one.

This is my 1st try at making Feminized seeds using Colloidal Silver (never really tried to look at something like this before)..Am I dreaming, or is the Pollinated Bud making seeds in those sacs with the pistils dried out and not making new ones? (the other bud is on the same plant )

Cackleberry Feminized pollen x Cackleberry Clone (both from the same mom..S1s??)
TIA

IMG_1017.JPG
 
xavier7995

xavier7995

Really good description man. Obviously the selection aspect made sense but I never fully got what people meant by back crossing and always assumed when breeding the plants out you would select a male and female from the second generation that had the desired traits and then from the third generation and so on. This is obviously a much more practical way to get the exact traits you want.

Just to pick this back up for completions sake, what you are describing is called line breeding as far as i know. If you have the time and space, that is the way to go. It is how those stellar dutch varieties came to be, but you have to run thousands of plants. Maybe work like that will be done again someday now that going legal has started to spread. But given the world we live in, back crosses seem to be the way to go.
 
MisterSkunk

MisterSkunk

For me bx'n isnt what I want. The initial cross gives me many phenos to work with and I dont want more of 1 streign in the mix than the other. I know IBL'n multiple times is debatable but tends to give the better finished result. Especially when using very opposite streigns.
 
Skipper23

Skipper23

So if I have an original Trainwreck that seems to be getting tired, I could effectively rejuvenate her by grabbing pollen from any strain, pollinate Train, take pollen from male offspring, pollinate Train again, do this 2 more times, and I have a fresh Train again?
 
Skipper23

Skipper23

Thank you.
What ways can I reverse the train to get some pollen? There's always banana pre flowers but they're never fertile.
 
MisterSkunk

MisterSkunk

If u have bannas on the Wreck along with pistils, Im not sure I would keep it. That implies instability and will likely carry over in a cross of any type. Now if ur stressing it some way, just stop and ease back then see if naners come out and play.
Thank you.
What ways can I reverse the train to get some pollen? There's always banana pre flowers but they're never fertile.
 
malamus

malamus

when I backcrossed my GDP male it took 3 rounds to get all phenos stabilized and the fourth pushed all phenos to the GDP side. there was an round of inbreeding in between
 
H

hawkman

when I backcrossed my GDP male it took 3 rounds to get all phenos stabilized and the fourth pushed all phenos to the GDP side. there was an round of inbreeding in between
use breeded seeds (1) to female then breed seed(2) to female then breedseed (3) THEN FEMALE IS PURE ? (3 BACK CROSSES) DO i HAVE ANY IDEA
 
malamus

malamus

pretty much, depending on the first breeding parent line they might or might not be pure after the third bx, mine were not until two more steps but again it will depend on the parents' stability
 
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