Filial Generations....

We hear the terms F1 and F2 thrown around a fair bit when referrring to cannabis breeding , but what does it really mean ??

Mendals legacy ...

Mendels genetics are frequently referred to as mendelian genetics , as gregor mendel discovered the principals of genetics in the mid 1800s , his most famous experiments were done with garden peas ..
mendel used peas that bred true for particular traits , ie green peas and yellow peas , he crossed a yellow pea plant with green , these two were referred to as the parental generation , abbreviated as the p generation , the fresulting offspring became the first filial generation of f1 genertatoin , these f1 plants were all yellow peas , mendel selfed the f1 plants ... 'selfing ' is when dthe pollen from a flower is used to fertalise the female part of t his same flower , by breeding the f1 generation with itself he produced a second filial generation of f2, mendel found that three quarters of his f2 generation were yellow peas and one quarter were green ..
These results lead mendel to propose theat each pea plant carried two genes for each trait and a parent could pass only one of its two genes for a given trait to its off spring , he surmised that since the f1 plants wer all yellow , this was a dominant trait and represented it with a capital Y,Green . which reappeared in the f2 generation , was recessive and therefore hidden in the f1 generation and he represented this with lower case y .
Each trait (eg colour) gets one letter asssigned to it ; this indicates that you have two forms (dominant and recessive )of the same trait and the alternative forms of the gene are called alleles (for example y or Y)
Mendel used interbreeding of filial generations to isolate and highlight the dominant and recessive action of the particular trait in the is case yellow and green pea seed, without outside genetic influence ..

SUMMERISING MENDEL.
The first filial generation are the offspring of a specific outcross mating: this is usually abbreviated to F1.
The second filial generation (F2) is the offspring of interbreeding the F1 generation , ie brother mated to sister .
Mate two f2 individuals and you get the third filial generation (F3) and so on .
Interbreeding the offspring from each succeeding generation brother to sister gives successive filial generations . This helps isolate the desired trait without outside genetic influence ..

[SupaDave]

Wow Wally, u making my head hurt, hehe.
I'll leave the brainiac stuff too you breeders, just make it so i can afford it.

SD

[JLP]

Nice post Wally

One note of interest:Mendel was working with a-sexual plants,meaning that each plant has both sexes(not a hermie)and pollenates it's self naturally,usually with the help of bees or man.So you only need one plant to create F2,however Cannanbis is Diocius(sp?) which means it has seperate male and female plants.With Cannabis you have to breed 2 siblings from a F1 gen to create an F2.
With Cannabis,"selfing" is an entirely different thing.Only recently have I seen the term "S1" to indicate a selfed cannabis plant ,but I suspect the term "S1" is made up and not an actual scientific term.


JLP

[bartender187]

Nice info, cleared up alot of misconceptions.

Mendel's Beans..... ahhh... its all coming back to me, freshman biology.

thanks
bartender187

i did wonder what the latest s thing meant jlp , was afraid to ask and look ingnorant .. lol .. still think id prefer a male and female combo , as it was intended so to speak .. lol ..

Good stuff. You guys are gonna get me edumacated in spite of my feeble mind.

[JLP]

I've been reading about "selfing" or feminized seeds for a couple years now.If you search Sam the Skunkman's posts over at OG you'll learn all you want to know about this process.

Basically you take a female plant and apply a chemical,usually Giberellic Acid or STS,to stress the plant into producing male flowers.The pollen created will contain no male chromasomes,therfore all the seeds created from that pollen should be female.
The one fly in the ointment is if that if you start with a female that has a hermaphroditic trait,you will most likely see it re-occur in the seeds.
This is not too much of a problem as long as you have seeds of the strain you want to femminize.You can grow them and introduce natural stress to the plant.Irregular light cycles are the easiest,but extreme high temps are worth a try as well.If the strain has a recessive hermie trait it will usually show under natural stress and you can select strains based on thier hermie resistance.
I'm not entirely sold yet on femmed seeds but I've got my first femmed seeds going now.I've got 2 DP Strawb Cough which are looking like fems so far.


JLP

hey guys, ive grown a selfed SC clone and selfed BB sativa and have selfed purp kush at 8 weeks veg.

ive only experienced a hermie in the SC which were S2s, they are not clones in seed form, you will see variation from the seed. and chances of pullin the elite clone from the seed is about as good as from regular seed. even had a full blown male in the SC. and have heard of a male in the PK from other growers. a product from called sensi soak was used in the SC and PK. the BB sativa was from reeferman and i dont know exactly what he used in the process.

the BB sativa was excellent and am currently growin another pheno that is quite a bit more BB and may end up bein the purple pheno i am lookin for in the seed. the first two were very sativa with airy braided bud. great smoke. old sativa tastin.

IMO selfed seed will be as good as the stock used from the start. and of course the breeder that made the selfed seed. I havent been dissappointed in any of the seed, and has produced some pretty good bud. for those that dont have connections for clones, or dont care to recieve um in the mail. selfed seed are another option in findin the special clones that float around.

that SC male was used to produce more SC beans.( done by a friend that I sent beans to to go over) I am still hopin to find that SB pheno in those beans.

CBF