Our Process
Yggdrasil is constantly working to add variety to our program of genetics while also refining the cultivars that have gained traction with our customers to improve consistency from seed to seed and bring out favorable characteristics.
We routinely carry F1 stock, BX1, S1, and F2’s. To help with clarification on the terminology of plant genetics, here is a breakdown as to what all the labels mean:
F2
An F2 plant refers to the second filial generation that is produced when two F1 plants (from the first filial generation) are crossed, or when an F1 plant is self-pollinated. F2 plants are the result of a genetic recombination process, which leads to greater genetic variability compared to F1 plants.
Here are some key points about F2 plants:
Increased Genetic Variation
Unlike F1 plants, which tend to be more uniform, F2 plants can show a wide variety of phenotypes. This is because genetic traits from the P1 (parental) generation can recombine in different ways in the F2 generation, leading to plants with varying characteristics such as growth patterns, potency, flavor, and resistance.
Segregation of Traits
In the F2 generation, traits can "segregate," meaning that recessive traits that were not expressed in the F1 generation can appear in the F2 generation. This results in less predictability in terms of traits when compared to F1 hybrids.
Breeding Selection
F2 plants are often used by breeders to identify and select desirable traits. Breeders can choose individuals from the F2 population that express specific traits they want to stabilize in subsequent generations.
In cannabis breeding, the F2 generation is where more variation emerges, allowing breeders to further refine and stabilize strains by selecting plants with the most desirable characteristics. However, F2 seeds tend to produce more variable offspring than F1 seeds.
BX1
A BX1 plant refers to a plant created through a process called backcrossing. In backcrossing, a hybrid plant (usually an F1 or another cross) is crossed back with one of its original parent plants to reinforce or stabilize specific traits. BX1 stands for the first backcross generation.
BFor example, this is how a BX1 generation is created:X1
1) A breeder crosses two distinct parent plants (P1 and P2) to produce an F1 hybrid.
2) The F1 hybrid is then crossed back to one of its original parents (usually the parent with the desired traits), resulting in the BX1 generation.
Key characteristics of BX1 plants:
Trait Reinforcement
Unlike F1 plants, which tend to be more uniform, F2 plants can show a wide variety of phenotypes. This is because genetic traits from the P1 (parental) generation can recombine in different ways in the F2 generation, leading to plants with varying characteristics such as growth patterns, potency, flavor, and resistance.
Genetic Similarity
BX1 plants will typically carry more genetic material from the parent they were backcrossed to, so they are more genetically similar to that parent than the F1 plants. However, they still retain some genetic diversity from the other parent.
Further Backcrossing (BX2, BX3, etc.)
Backcrossing can be repeated over multiple generations (BX2, BX3, etc.) to continue stabilizing traits. Each successive backcross makes the plant more genetically similar to the original parent.
In cannabis breeding, BX1 plants are often used to stabilize traits like potency, flavor, or structure. However, repeated backcrossing can also reduce genetic diversity, which may increase the risk of inbreeding depression (loss of vigor, yield, or resistance to disease).
S1
An S1 plant refers to a plant that has been produced through self-pollination, typically within the same strain or genotype. In the context of cannabis breeding, S1 stands for the first filial generation derived from a self-pollinated plant.
Key Characteristics of S1 Plants:
Self-Pollination
S1 plants are created by forcing a female plant to produce pollen (usually through methods like stress or the use of a chemical agent such as colloidal silver or gibberellic acid) and then using that pollen to fertilize itself. This results in a seed stock that carries only the female plant's genetics.
Genetic Uniformity
Since S1 plants only receive genes from a single parent, they tend to show more genetic uniformity than regular hybrids, making them more predictable in terms of traits like potency, terpene profile, and growth patterns.
Trait Stability
S1 plants are often used to stabilize desirable traits. If the original female (mother) plant had particular qualities that the breeder wanted to preserve (such as high yield or a unique terpene profile), an S1 generation can help lock those traits into the gene pool.
Increased Homozygosity
Because the S1 generation comes from a single plant, there is an increase in homozygosity (similar gene pairs). This can enhance consistency in offspring but may also expose recessive traits, which could be undesirable in some cases (such as reduced vigor or increased susceptibility to diseases).
Feminized Seeds
Since only female plants are involved in the process, the seeds produced from self-pollination will often result in feminized seeds, meaning the offspring are highly likely to be female. This is particularly useful in cannabis cultivation, where female plants are valued for their buds.
S1 seeds are popular among breeders looking to preserve the characteristics of an exceptional "clone-only" strain and replicate those traits in seed form. However, selfing (self-pollination) can lead to some genetic bottlenecking, where the lack of diversity might result in less resilient plants over multiple generations.