[Jose Hernandez]

Can someone tell me if I have this right? an f1 seed is an original cross between two diferent strains and an f2 is a cross of the same strain? Is there any degredation of quality from an f1 to an f2 if I am correct? I grew a nl #5 x dj short blueberry for a while and lost the strain to a nessesary clean out due to spider mites. Anyway I had a few beans the strain produced before I weeded out all the herms. This time around it just doesn't seem to have the potency the original clone had. It grows strong, it looks great, the resin glands just seem to be fewer and smaller. I don't have an original sample to compare it to so it could be all a misconception but I'm pretty sure it used to be danker.

I tried to add a pic but I am not sure how to do that yet, I guess I need to add it to the photogallery first. I'll post it in a min.

[Raoul]

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

[Jose Hernandez]

Thank you so much for the very helpful, well thought out answer! so, the original nl#5x blue cuttings I had from the original seeds where F1 hybrids and when it crossed with it's self the beans from that where two F1 s crossed making them F2 hybrids and since they are f2 s. And f2 beans produce less consistent plants so this time around it may very well not be as good as the original. thanks again man! would this also make the original cuts from the first mother is a P1 for me? I am going to try and post a pic of the f2 northernberry aka nl#5 x blueberry

it is my understanding that in the f2 generation more genetic diversity is there so you may get plants looking from as extreme as one parent to another and mixes inbetween.
basically you get more variance from the whole gene pool in the f2 cross from both sides of the family. but maybe i interpreted wrong in my readings, but in my experiments it seems to work like that also.
peace
pout

[ProGroWannabe]

That is right poutpup. I really like looking through f2's. Sometimes you can find some real gems in there.

[Jose Hernandez]

Hey, I'm not saying that the f2 northernberry isn't dank, it is pretty good. I just think this time around the one true mother I got just wasn't quite as fruity or frosty as the original mother and that genetic disposition to sway one way or the other just swayed the other way for me I guess. I am just happy I didn't lose the strain entirely. many thanks for the comments.