Basic nomenclature of cannabis genetics

Dani Alchimia 2024-01-22
Hi Matt, At least here in Europe, there's a lot of misunderstanding with regard to the term "pollen" (many people call hashish "pollen"). We just wanted to make clear that we're talking about the same pollen produced by males, not what many people understand as "pollen" (that is, hashish). Thanks for your input! ;)

Dani Alchimia 2023-06-27
Hello, I'd say that what you have is Zambezi landrace x blue magoo bx2 (a second generation backcross to Zambezi, which we'll call "A") then crossed with Fruitcake, which we'll call "B". I guess the "F1" comes from the first filial generation of the A x B cross. Hope it helped!

Dani Alchimia 2022-12-12
Hi Caesar La G, Those seeds are carrying both genes, the ones from the Mac&Cheese and the ones from Venom OG. What traits will be shown mainly depends on the dominance of these traits, so I'm afraid we'll have to just wait and see the results of the cross. In other words, imagine that the Mac and Cheese was a male: the offspring would show a combination of dad's and mom's genes according to their dominance. Same here. Best!

Tim Alchimia 2022-10-17
Hi and thanks for your comment. I have to agree, it makes me cringe a little when I hear that too - it's not mathematics! I believe that you're right, in the world of animal breeding, the correct way to say "x" is "by". Personally I tend to say "crossed with" or "pollinated with" but that's just me trying to avoid saying "times". All the best and happt growing!

Tim Alchimia 2022-08-29
Hi, thanks for your comment and question. The accepted practice when writing the genetics of a hybrid is to put the seed-bearing plant (ie. the female) first, followed by the pollen donor, which can either be a male in regular seeds, or a reversed female in feminised seeds. Obviously, there will always be a few breeders or seed banks that don't follow this protocol, whether by error or ignorance, but in most cases, we can expect to see the name of the female written first, so in your case, the Blueberry would be the female and Haze the male or reversed female. I hope that helps. Best wishes and happy growing!

Tim Alchimia 2022-08-01
Hi and thanks for your comment and question. There's no reason why not to use an S1 as a mother plant to pollinate with a regular male. As long as the plant has all the characteristics you're looking for and has proven to be sexually stable (no hermaphrodite/intersex traits), it should be fine. The genetics you mention certainly sound like a great combination of high-quality varieties, so you'll just have to make some crosses and grow out the resulting seeds to see if your mother plant passes on the qualities that you want. Best of luck with your breeding project, happy growing!

Tim Alchimia 2022-06-24
Hi, thanks for your comment and question. If the clone-only strain you have is exactly the same clone used by the original breeder to make the S1 seeds, then the resulting seeds would indeed be a back cross. US seed bank Ethos Genetics do a lot of this kind of feminised inter-breeding and they would label these seeds as RBX which stands for Reversed Back Cross. I hope that clears things up. Best wishes and happy growing!

Tim Alchimia 2021-11-29
Hi, thanks for your comment and questions. With regards to your first question, it would all depend on the stability of the keeper mother plant that you're working with. There's no reason for feminised seeds to result in more hermaphroditic plants than regular seeds, as long as the parents used are themselves sexually stable. I'm a bit confused about the second part of your question though, if I understand it correctly, and to use your terminology, you have some Bxf3 seeds, which would be the 3rd filial generation of a backcross: ie. you made the backcross then bred the resulting male & female plants together for 3 generations, right? If so, by crossing a Bxf3 male back to the Bxf2 female that it came from, yes you would indeed be making an inbred backcross but it wouldn't be a Bx2f1. I hope that makes sense. Best wishes and happy growing!

Tim Alchimia 2021-10-19
Hi, thanks for your comment. S1 seeds come from a process known as "Selfing". So, to make an S-generation seed, one would have to reverse a plant to itself. This means that to make S2 seeds, one would need to select a single plant from the S1 seeds (usually the one that most resembles the original clone that made the S1 seeds) and then "self it", reversing it to a clone of itself. Then, to make S3 seeds, select the best example from the S2 generation and reverse that to a clone of itself, and so on until the breeder feels that the resulting plants are as consistently close as possible to the original clone. Of course, you can do as you suggested and select 4 S1s, reverse one of them and pollinate the other three, but in this case, it wouldn't be an S2 because you wouldn't have "self-pollinated" a single plant. I believe that this filial generation of reversed seeds would be referred to as "R2". I hope that clears things up. Best wishes and happy growing!

Tim Alchimia 2021-09-16
Thanks for your comment and kind words. It's true that some seed banks like to keep any genetic information to themselves and, personally, I've always mistrusted those that do. Good quality seeds can come from many different sources and seed banks but I like to support those that are completely transparent about their breeding process. For a great example, you can check out ACE Seeds, who on their website publish in-depth breeding notes, detailed characteristics and growing tips, possibly the best in the business. It's reassuring to know a breeder has actually grown their own gear, unlike so many seed banks releasing untested crosses based simply on the fame of the clone-only parent plants. Of course, some growers want to have the newest and most exclusive seeds so I understand that there's a market for those untested seeds and they're popular nowadays. Regardless of that, a good breeder should at least be able to tell you the parents and whether the variety is an F1, F2, backcross, S1, open pollination, etc. I hope that helps. Best wishes and happy growing!

Tim Alchimia 2021-06-21
Hi Nick, thanks for the kind words, I'm happy we've been useful! I really like the sound of your project, I think it's a good idea and I think your reasoning behind crossing cousins is sound. Looking at it from my personal perspective, I would avoid selecting just one male from each of the varieties. With the females, it's a lot easier to see that a particular plant has the characteristics you're looking for, whereas with the males you'll need to make the seeds and grow them out before you can be sure that a particular male passes on the desired traits. For this reason, and also to avoid any genetic bottleneck, I always prefer to use multiple males, as many as possible, only rejecting those that have observable negative traits such as low resistance to pathogens or a lack of vigour, for example. This way, you'll be sure to get as wide a range of expression as possible within the selected gene pool to work with from that point onwards. I hope that helps, best of luck with your breeding!

Tim Alchimia 2020-06-25
Hi, thanks for your comment and question. First, it's vital to understand the process behind making feminised seeds. A reputable seed bank will go to great lengths to select sexually stable parent plants before embarking on any feminised seed making. This involves thoroughly stress testing the plants and rejecting any that show hermaphroditic tendencies. This selection ensures that the resulting feminised seeds do not carry any hermaphroditic traits and that the sex reversal used to produce the female pollen will be entirely due to the use of Ethylene-blockers and not due to genetic intersex characteristics. This is quite different from stress-hermied bag seeds, which entirely owe their existence to the parent's sexual instability and will most likely carry that trait forward in their offspring. Unfortunately, this is exactly how the first commercially available feminised seeds were made, and for that reason, they quickly and justifiably gained a bad reputation as being hermie-prone. Thankfully, things have come a long way since then but there are still plenty of opinions that need changing! So in short, yes, you absolutely can breed with plants from feminised seeds, as long as you first put in the proper stress-testing to ensure that they are sexually stable. Once you're sure they're stable then they can be treated just like any other female cannabis plant. I would strongly recommend that you stress-test the male you plan to use as well, just because a plant comes from regular seed is no guarantee it will not hermie, in fact, in my own personal experience I have had far more regular plants show intersex characteristics during stress testing than with feminised plants! Of course, if you want to preserve a particular pheno then the most reliable method is by vegetative propagation i.e. taking cuttings/clones. I hope that helps, best wishes and happy growing!

Tim Alchimia 2020-06-15
Hi, thanks for your comment and question. In theory, yes, that's exactly how you would create a stable IBL (Inbred line), but in practice, it depends a great deal on the selections the breeder makes at each generation, as well as whether the traits being selected for are dominant or recessive. From what I've read, an IBL can be created in as few as 5 generations, as long as the correct selections are made at each stage. On the other hand, if the wrong choices are made it would be quite easy to arrive at F7 without achieving uniformity while reducing vigour and viability through inbreeding depression. So yes, but careful selection of "keeper" plants, particularly at the F2 stage, is vital. I hope that helps, best wishes and happy breeding!

Tim Alchimia 2020-05-20
Hi, thanks for your comment and question. In short, yes the seeds will be feminised, or at least 99.9% certain to produce female plants. You'll have produced an Amnesia S1 and God Bud x Amnesia. However, I would strongly advise against germinating them and growing them. This is because they are the product of a hermaphrodite pant and will, therefore, carry this hermaphroditic trait on to its offspring, meaning you'll be much more likely to have the same problem with future crops, resulting in your buds being seeded again, which I'm guessing is not what you're looking for! I understand that you'd like to salvage something from your seeded crop by planting the seeds, but you will most likely only be causing more problems for yourself in the future. The difference between feminised seeds and hermaphrodite seeds is that to properly make fem seeds, a breeder must first select plants that have minimal (or none at all) hermaphrodite characteristics, this is done by stress-testing the female plants and rejecting any that show male flowers. Then, one of these "sexually stable" plants is treated with a chemical that effectively works to suppress the female flowering hormone and leads it to make male flowers, which produce feminised pollen. Reputable breeders and seedbanks will go to great lengths to avoid using unstable parents in their hybrids, mainly because of the flood of complaints and returns that they would no doubt experience from customers unhappy about all their ruined crops! By all means, feel free to germinate and test these seeds and please let us know how you get on. However, I fear that you may end up regretting it when your next crop is also seeded, effectively negating any saving you may have made by using homemade seeds. Good reliable seeds from a reputable breeder are some of the most important investments a grower can make! Whatever you choose to do, best of luck and happy growing!

Tim Alchimia 2020-05-15
Hi Klean, thanks for your question. You're correct, it can definitely be a little confusing to work out the genetics in these cases. If a seed bank displays the lineage as simply A x B X C then there's really no way to know how the cross was made. The proper way of writing it is as so: (A x B) x C in which case the female is A x B and the male would be C. Alternatively, A x (B x C) would indicate that the female was A and the male was B x C. Without the brackets it's anyone's guess! Incidentally, the female (or seed-bearing plant in the case of feminised crosses) is always listed first, with the male last. Having said that I have seen breeders list things the wrong way round and state that it isn't important. Personally I wouldn't buy seeds from anyone who can't get something so basic correct! Hope that clears up any doubts. Best wishes and happy growing!

Tim Alchimia 2020-05-04
Hi Tobs, thanks for your comment and question. In this case, the S1 offspring won't be identical to the mother plant. Look at selfing like you're basically taking all the genetic information contained in that one plant and "rolling the dice" again, in other words, recombining the same genetics. The results will depend on the genetic stability of the mother, so a poly-hybrid (like most of the modern varieties out there these days) will produce a great deal of variation, a true F1 hybrid (made bt crossing 2 stable, inbred genetic lines) will give some variation while a well-made IBL (In-Bred Line) plant will reproduce fairly faithfully as an S1. If I was to set about trying to reproduce a plant in seed form, I'd probably make S1 seeds then grow out a good quantity of them to select the plants that most resemble the mother. Then I'd probably try either reversing and back-crossing one of these offspring to the mother again, or I'd take the two offspring that most resemble the mother and cross them together. I think that could be a good way to fix the traits you're looking for. I hope that's useful, best wishes and happy breeding!

Tim Alchimia 2020-04-11
Hi Pugun, as a general rule, the female seed-bearing plant goes first in the description of the cross, so if, for example, you pollinated an OG Kush female with Skunk #1 male pollen, the cross would read OG Kush x Skunk #1, and likewise if you were to pollinate the OG Kush female with pollen from say a reversed Forum Cookies female, then the cross for the feminised seeds produced as a result would be OG Kush x Forum Cookies. I hope that helps clear up any confusion. Best wishes and happy growing!

Tim Alchimia 2019-11-22
Hi Thomas, thanks for your question. There's no negative aspect to making your own seeds, although selecting the parent plants which you will use to make the seeds is an important step in the process. Choose one, two or more females that have the characteristics you're looking for, and then pick a male or two that match them. Of course, you can make seeds with just one of each parent, but there's always the risk of creating a "genetic bottleneck" when working with a limited number of plants. This can lead to inbreeding depression, where detrimental recessive genes are allowed to proliferate. When working to reproduce a line such as Skunk, I would recommend using as many parent plants as possible, but being sure to reject any weak or mutated plants. I hope that helps, all the best and happy breeding!

Tim Alchimia 2019-09-17
Hi bettyloo, thanks for your comment, I'm happy to hear you're making your own cannabis and tomato crosses and that the article was useful. I'm a big fan of SSH myself, it was one of the first clones I grew around ten years ago. Definitely a good variety to work with, it's sure to improve most anything it touches! As for the labelling, if I understand it correctly, you have clones of 2 old varieties and you've crossed them both with SSH, and then crossed the offspring of each cross back to the clones? If you're working with non-feminised ie regular genetics, with males and females, and pollinating the original clone with each successive generation, then what you're doing is backcrossing, and once you made the initial outcross (with SSH) the generations would be Bx1, Bx2, Bx3 etc. S1, S2, S3 etc would be if these were feminised backcrosses, where the plant was reversed and the pollen used to pollinate another clone of the same plant. S2 would be a case of reversing a selection of the S1s to the original clone, or vice-versa. I hope that answers your doubts, if not, please let me know! I wish you all the best, and continued success with your hybrids, happy growing!

Tim Alchimia 2019-06-28
Hi Keith, thanks for leaving your comment and question. Yes, males will usually tend to be more tall and lanky than female plants, I'd imagine that this is a trait that evolved to allow them to stand over the females and spread their pollen further than if they were the same size as them. As for selecting a male, it's not an easy process. You can start choosing plants based on visual and olfactory traits such as structure, colour, leaf shape and aroma when rubbing the stem, selecting the individuals with traits that match the mother plant you want to stabilise. Unfortunately, though, there's no short cut when it comes to knowing what traits the male will pass on to the offspring. The only way to be sure is to make seeds and test the progeny, which is a long and potentially costly process. Another option would be to make a backcross of your mother plant. This involves making an initial outcross with a different male and then pollinating the mother with the males from this first outcross, creating the BX1 generation (backcross). Maes from this BX1 generation could then be used to pollinate the mother again, creating the BX2 generation, and so on, in a process known as "cubing". I hope that's answered your doubts, if not please let us know. All the best and happy breeding!

Tim Alchimia 2019-06-04
Hi Aaron, thanks for your question. Strictly speaking, a true F1 would be a cross between two unrelated, stabilised (inbred) lines, however, these days the cannabis world uses the term for any cross between two different plants. In this case, I'd probably label the cross F1 OP (for open pollination) just for clarity. Hope that helps, all the best and happy growing!

Tim Alchimia 2019-01-30
Hi MichiGreen, thanks for your comment. In short, yes you're correct. The vast majority of seeds available these days are poly-hybrids, or poly-hybrids of poly-hybrids! Cannabis trends/fashions and the speed they move mean that very few seed banks are willing to put in the work required to properly "stabilise" a strain before releasing it, preferring instead to simply cross one hype clone with another and release the results. For the most part it seems to matter little, as many growers these days are happy to "pheno-hunt" for a spectacular example, different to anything anyone else has, that they can clone for future crops, rather than expecting to sow 10 seeds and end up with ten almost identical, "stable" plants. However, with the advent of legalisation in different countries around the world, it's more likely that good, conscientious breeders will be able to make careful selections from large populations of plants to breed with. Hopefully we'll see some progress in that direction and get some stable seed lines. All the best, happy growing!

Tim Alchimia 2018-08-08
Hi again Sam, and thanks for the comment. OK, so if I understand this correctly, we should be talking about uniformity in cannabis plants rather than using the term "homogeneity"? I get that in genetic terms there's a difference, and that cannabis isn't homozygous, it's heterozygous, but can we not describe plants as homogeneous in appearance and behaviour? Personally, I'd argue that homozygous and homogeneous aren't the same, they mean two different things, with homozygous referring to a gene having two matching alleles, while homogeneous, which as far as I know is not a term with a genetic basis, refers to uniformity. I think it's probably fair to describe as homogeneous a seed variety that consistently produces plants with an almost identical appearance, behaviour, terpene profile and effect, even if it isn't homozygous, genetically speaking. Is this wrong? All the best and thanks again for your contribution.

Tim Alchimia 2018-08-08
Hi Sam, thanks very much for your input, it's really very much appreciated. I'm going to edit the post to replace the term "strain", that's a good point, thanks for pointing it out. This article was originally written in Spanish and later translated to English, so that may explain it to a certain extent. Believe it or not, we're fully aware of the terms proposed by Karl Hillig, (just to confirm, should it be BLD Broad Leaf drug or WLD Wide Leaf Drug? I've seen both used) and while we do sometimes use these terms where appropriate (and we'd like to use them more), we're not writing scientific studies here, we're just trying to inform and help out your average home-grower. I agree, it's important to be educated in order to educate others, but I also think a balance needs to be struck between strict scientific accuracy on one hand, and accessibility of information on the other, we need to present things in way that can be easily understood, without requiring too much additional explanation: everyone knows what we're talking about when we say "Sativa, Indica or Ruderalis", and as I'm sure you're aware, most growers couldn't give two hoots about using the proper botanical terms, indeed some are proud of not using them! It's an interesting subject, and one that we'll probably address in another post fairly soon. I'm all for teaching our readers the correct terms to use when talking about cannabis, but whether they actually use it or not is another matter. Like they say, you can lead a horse to water... Thanks again for taking the time to comment, all the best!

Dani Alchimia 2018-06-25
Hi Nicolas, Tim is on holidays, so I'll reply your comment. Well, since "F1" theoretically means "first filial generation", I often call my crosses "F1" no matter if they come from a single landrace, from two different landraces or from hybrids. Some people will tell you that it only stands for a cross between two different landraces, although most breeders call the first filial generation "F1" regardless the genetics/parents used to develop it. Hope it helped!

Tim Alchimia 2018-03-29
Hi Ripper, thanks for your comment. That's pretty much what I was saying, a true F1 is a cross between two genetically distinct but true-breeding pure lines. My point is that you can't cross two modern poly-hybrid strains together and call the progeny a true F1. All the best.

Tim Alchimia 2017-12-15
Hi Dennis, thans for your question, you're right, it's not common to see that kind of information on cannabis seed packs or catalogues. This is probably because most cannabis breeding isn't carried out by qualified geneticists specialising in botany, but by enthusiasts and veteran growers, meaning that much of the terminology employed by professional geneticists is either misused or not understood in the cannabis seed indusrty. A true F1 hybrid should be a cross using two different, pure varieties, however much of what cannabis breeders refer to as "F1" are crosses between hybrids or polyhybrids and so are not strictly "true F1" hybrids. If you're looking for good F1 hybrids from reliable and trustworthy breeders, from my own personal experience I can recommend three Spanish seed banks: ACE Seeds, Cannabiogen and Tropical Seeds, and also a great French seed bank Underground Seed Collective, all of whom do some great work with pure landrace genetics, producing some spectacular F1 hybrid seeds. I hope that helps, all the best!

Tim Alchimia 2017-12-15
Hi Daniel, thanks for your question, sorry for taking so long to answer, I'm afraid it must have slipped through the net! In answer to your doubts, yes! Many people worldwide have experienced huge success using cannabis as an alternative to pharmaceutical treatments. There is an ever-expanding library of online articles and studies into this subject and as the legal situation improves in the USA we can expect to see even more scientific evidence as to its efficacy. Have a look at the section of our blog that deals with Medical Cannabis and if you have any more questions then leave a comment for us on the appropriate post. All the best!