A question for breeding experts.

[HempKat]

I'll have one more stab at it too. Anybody who gives a simple answer to this question doesn't know what they are talking about.

There is no evidence that suggests any of the traits we are breeding for are sex-linked in cannabis. It used to bother me somewhat that I had observed vastly different ratios of intersex males:females in the same line but this could be explained away via various hormones affecting/modifying intersexed males differently from intersexed females.

So if we accept the above to be true -and I really believe we have to or start breeding by way of bizarro unfounded theories- we can cease all this BS that has come before on this topic. This is not a simple question, and the answer has never been simple either. So let's get past that before we can even begin.

What we are really talking about is which to use to increase the odds of success.

Immediately and unavoidably we need to start talking about things such as heterozygosity, homozygosity, phenotypic evaluation, genotypic evaluation, etc, etc, etc.

It is extremely difficult to place a phenotypic value on a male drug cannabis plant (as apposed to females), we are not breeding hemp. So we need to observe its progeny, to place a genotypic value on it, this is what matters. What might we do to increase the odds of success?

Here is just one single example:

Let's say I have an F1 cross in mind, a Mexico/Afghanistan and that quality of smoke is highest on the list of goals. They both are relatively true breeding (homozygous) for many traits. However, they differ in the percentages of high quality smoke within their respective populations. Let's say that the Mexico has historically/generationally held a much higher percentage of individuals per growout that were exceptional smoke. Ok, then we'd likely be correct in assuming that quality of smoke was more fixed (homozygous) in the line from Mexico. So to increase the odds of success, we're going to be testcrossing males from the Mexico population to phenotypically selected females from the Afghanistan population. Because we know we don't have to look as far through the Mexico population to find what we're looking for in comparison to the Afghanistan population.

Can't have the conversation without these types of considerations, once we get past this not being a simple question with no simple answers. -Tom

Okay to sum that up into a short sweet answer are you saying that the one that is closest in character to the goal you're seeking should be the male?

 

[HempKat]

I think that I have this figured out properly ... WRONG! (Far too long since HS biology ... )

A big thanks to TomHill for this link: http://www.changbioscience.com/genetics/punnett.html

AA = Homozygous Dominant
aa = Homozygous Recessive
Aa = aA = Heterozygous

AA x aa ==> 1 AA + 2 Aa + 1 aa
AA x Aa ==> 1 AA + 3 Aa
aa x Aa ==> 1 aa + 3 aA

Here's the real quandary: Does the characteristic that you are seeking in your breeding program express itself when that trait is dominant, or when it is recessive? That is for a single gene -- is there one or more additional co-dependent genes (B,b,C,c,D,d) involved in the expression of that desired characteristic? And what part do changes in environment play in aiding the plant's expression of that characteristic?

It would appear that any effort to cross and stabilize your plant for any one desirable characteristic without thousands (many thousands?) of samples to work with is, at best a crap shoot. And without the addition of luck and happy circumstance, it would take many generations of plants to achieve. Many|most|all seed houses deserve our respect and gratitude.

Without a doubt, if they are going thru the types of methods being described here then it becomes clear that the prices breeders charge are not as unreasonable as some think.

In asking the question I asked, I didn't really have anything specific in mind. I referenced a cross I had recently made with GodBud but only because it was in making that cross I began to wonder about how you choose which plant gets to be male and which gets to be female. With the GodBud I never got a chance to try it as out of the 10 seeds I was given only 3 germinated and all 3 ended up being male. I heard good things about GodBud but I have no clue what that pollen passed on other then maybe a tendency to grow a short broadleaf indica. There was no choice in that though. I'm wanting to know that if I have two strains that would make a good cross in my mind and I can choose which is the male side of the cross and which is the female, what is the criteria for choosing? I think I have that answer now but that's what I was getting at.

Also while I understand that to get a good, stable, sellable product you need to go thru the large numbers and the selections to stabilize things. That however is just never going to happen in my 5' x 8' x 8' grow room for something that only I and occasional friends might ever grow. So in light of that I had hoped to learn if the choosing of which strain in a cross is mother and which is father, I might increase my odds having the luck and happy circumstance of finding what I might hope to get from a cross.

 

[HempKat]

Also let me apologize in general to those of you who have been trying to help. I guess I didn't make my question clear enough in what I was getting at intially as nobody seemed to be answering in a way that really seemed to apply. Once I restated things though then the discussion started going more in the direction I was seeking, at least I think it did, I'm still waiting on confirmation of whether I understood what Tom was saying in his latest reply to my question or not.

 

[OsWiZzLe]

good info here

 

[Tom Hill]

Okay to sum that up into a short sweet answer are you saying that the one that is closest in character to the goal you're seeking should be the male?

No, if I understand you I'm not saying that, we can't simplify this like that.

You were earlier talking about not likely ever moving past the F1. (I'm assuming these parental lines breed true for a majority of traits. That they are not F1's or highly heterozygous hybrids themselves). Beyond that and looking deeper into the P1 and P2, into the genetic background of the populations, it is probably wiser to test as the male contribution the line with a deeper history in the trait we seek. This would be the line with the higher percentage of homozygous individuals - call this P1 for arguments sake. The percentage of advantage there would be some figure directly related to the percentage of homozygous individuals P1 held over P2.

If we are truly talking about a single cross hybrid (F1), then we may want to take some of that into consideration. If we're not, then the value of that wanes quickly. If we're just talking about crossing any old two plants then it's time to go back to BK's lecture on not bothering to seek homozygosity before the F2 etc, and just forget about any advantage at all of using this or that as the male.

 

[Unclepeter]

There is no evidence that suggests any of the traits we are breeding for are sex-linked in cannabis. It used to bother me somewhat that I had observed vastly different ratios of intersex males:females in the same line but this could be explained away via various hormones affecting/modifying intersexed males differently from intersexed females.

hmmm by this do you mean auxin and cytokinin effects or other things aswell? I have read of a sex linked mutant recessive on the x but I think from memory it was x ray linked and on work from late 30's..

as you know I look at silene alot... that seems to be moving away from the Y, to me its highly likely the Y is carrying lots of copy info..

anyway is it that its all sexual antagonism? and therefore all about fitness?

 

[Tom Hill]

Hi UnclePeter,

Yeah I was referring to any modifying factors be they autosomal or par, known or unknown, having the ability to affect sexual expression. This was really the only area where I was ever tempted to entertain the possibility of sex-linkage, but in the end I think that's probably not the case.

In layman terms looking at the Soprano family girls, and their mustaches, it's tempting to entertain sex-linkage. But really, it's just that factors influencing testosterone production are fixed at a high level in the family, and that has a different affect on the females than the males is all.

Hearkening back to DJ Shorts claims re the reverse hermies etc, many poke fun at it, but I do believe I am seeing the same thing over here. And yes, I also believe that it will be a case of suppression/antagonists that eventually sheds a bit more light. -T

 

[Baba Ku]

Tom, would you expand on the thing with DJ and the reverse hermies? Link?

 

[Tom Hill]

Hi BK I don't have a link but it is fairly common knowledge that DJ years ago placed some breeding value on mostly male plants with a few intersex (female) flowers -claiming that selecting them actually lessened the intersex tendency within a line. This caused an outburst in the community to put it mildly, and kneejerk reactions from those with some understanding of genetics were that a herm is a herm is a herm,,, and don't dare do it.

I'll assume that DJ was referring to the fairer sex in speaking of lessening intersex tendencies and expand in this way -> It is entirely possible and maybe even likely that the very same modifying factors giving rise to intersex expression in mostly male plants, antagonizes/suppresses the same tendencies in mostly female plants. And this would seem to quite handley help to explain vastly different percentages among intersex males and intersex females in the same line. -T

 

[highonmt]

Hi BK I don't have a link but it is fairly common knowledge that DJ years ago placed some breeding value on mostly male plants with a few intersex (female) flowers -claiming that selecting them actually lessened the intersex tendency within a line. This caused an outburst in the community to put it mildly, and kneejerk reactions from those with some understanding of genetics were that a herm is a herm is a herm,,, and don't dare do it.

I'll assume that DJ was referring to the fairer sex in speaking of lessening intersex tendencies and expand in this way -> It is entirely possible and maybe even likely that the very same modifying factors giving rise to intersex expression in mostly male plants, antagonizes/suppresses the same tendencies in mostly female plants. And this would seem to quite handley help to explain vastly different percentages among intersex males and intersex females in the same line. -T

Tom, This is a very interesting window into cannabis genetics and it is acutually borne out to some point by recent scientific findings regarding the lack of a distinct male chromosome in cannabis. Male sexual expression in cannabis is instead attributed to male linked genetic markers. Prehaps it is some type of sub dominant expression of the male sex marker in weakly pistillate males that leads to progeny with a suppressed male sexual expression. The more I learn about this pant the more there is to know great thread.. Thanks for sharing your knowledge and experience Tom.
HM

 

[Baba Ku]

Hi BK I don't have a link but it is fairly common knowledge that DJ years ago placed some breeding value on mostly male plants with a few intersex (female) flowers -claiming that selecting them actually lessened the intersex tendency within a line.

... It is entirely possible and maybe even likely that the very same modifying factors giving rise to intersex expression in mostly male plants, antagonizes/suppresses the same tendencies in mostly female plants.

Yes, I remember seeing him say this about the male that expresses intersex. I have always had a hard time wrapping my brain around what he was trying to convey, and it has to be that there may well be some sort of suppression of the trait when such a male is used.

 

[Unclepeter]

Hearkening back to DJ Shorts claims re the reverse hermies etc, many poke fun at it, but I do believe I am seeing the same thing over here. And yes, I also believe that it will be a case of suppression/antagonists that eventually sheds a bit more light. -T

I'll assume that DJ was referring to the fairer sex in speaking of lessening intersex tendencies and expand in this way -> It is entirely possible and maybe even likely that the very same modifying factors giving rise to intersex expression in mostly male plants, antagonizes/suppresses the same tendencies in mostly female plants. And this would seem to quite handley help to explain vastly different percentages among intersex males and intersex females in the same line. -T

mostly male plants sums it for me, I don't class them as males (though maybe they are!, perhaps like some say the only way is thru the markers?)... I have seen an upswing in female and intersex plants were a male like this was used.. but perhaps theres other reasons for this... some have suggested its an equilibrium (however spelt) thing ie ratio of males to fems in population.

 

[HempKat]

No, if I understand you I'm not saying that, we can't simplify this like that.

You were earlier talking about not likely ever moving past the F1. (I'm assuming these parental lines breed true for a majority of traits. That they are not F1's or highly heterozygous hybrids themselves). Beyond that and looking deeper into the P1 and P2, into the genetic background of the populations, it is probably wiser to test as the male contribution the line with a deeper history in the trait we seek. This would be the line with the higher percentage of homozygous individuals - call this P1 for arguments sake. The percentage of advantage there would be some figure directly related to the percentage of homozygous individuals P1 held over P2.

If we are truly talking about a single cross hybrid (F1), then we may want to take some of that into consideration. If we're not, then the value of that wanes quickly. If we're just talking about crossing any old two plants then it's time to go back to BK's lecture on not bothering to seek homozygosity before the F2 etc, and just forget about any advantage at all of using this or that as the male.

Whatever I have said about what I plan to do with this information was meant to convey I'm not trying to get into breeding or make something I'm going to then try to stabilize and maket or distribute. I'm just a grower who from time to time might make a cross of two plants thinking they might produce something really nice. In thinking about this I began to wonder how breeders go about choosing which strain in a cross takes the P1 role and which takes the P2 role. That's all I wanted to get at. I appreciate for people truely into breeding are going to want to take it alot farther then that because there is alot that goes into making a good product. I just figure there has to be something though that makes the breeder choose one strain to be the female and one the male. I figure if I get that down then should I ever change my mind and try to stabilize some cross I made, the starting point I'll be at will be correct. From what I gathered from your example of the Mexican/Afghani cross was that if you have one strain more likely to produce something along the lines of what you are looking for it's better to make it the father. If that's the case then you should be able to see where I gathered my summation from.

 

[Chronic Don]

so if you are not into the stabilizing of them why bother make some both ways. and if it as in the parents are not from a stabilized cross/breed then the outcome will be totally random. how-ever if IF one of them is a stabilized breed then use its male. then you can theorize it will pass that types pheno traits on, the female should/would pass on her own pheno traits mostly before passing on other traits. with the male how can you say it will pass on the traits in females you want since you cannot see those traits and what makes a "good" male is/can be way dif then what makes a "good" female.

so in other words to answer your original question there is no way to know for sure and by trial and error only will you find what you want in a seed

 

[Tom Hill]

UnclePeter once we deny the theory of 'true' females, all that leaves us with is mostly (or strongly if you prefer) males and females of varying strengths.

 

[Unclepeter]

UnclePeter once we deny the theory of 'true' females, all that leaves us with is mostly (or strongly if you prefer) males and females.

I think thats were i'm at with them then.... I think gerrit has seen sim things to you with regards to more fems... just leaves me scratching my head!!

https://www.icmag.com/ic/showthread.php?t=192711&page=2

 

[HempKat]

so if you are not into the stabilizing of them why bother make some both ways. and if it as in the parents are not from a stabilized cross/breed then the outcome will be totally random. how-ever if IF one of them is a stabilized breed then use its male. then you can theorize it will pass that types pheno traits on, the female should/would pass on her own pheno traits mostly before passing on other traits. with the male how can you say it will pass on the traits in females you want since you cannot see those traits and what makes a "good" male is/can be way dif then what makes a "good" female.

so in other words to answer your original question there is no way to know for sure and by trial and error only will you find what you want in a seed

Well for one thing to make them both ways and be sure what is what and that no contaminating pollen gets in I'd have to do them as two seperate runs given the space I have to work with. This would negatively impact the main reason I grow which is to supply myself, as seed bearing plants typically yield much less smokeable material then most sensimilla grown plants.

I also disagree that the answer to my question is there is no way to know for sure because at the point you have decided to make a cross you typically know what strains are going to be used, you already know what traits you hope to pass on so you'll pick parents that best express the things you want. My question never was how do you know what traits get passed on or how do you get to the end result of a stable new cross but rather when in the beginning of making a cross how do you pick which strain is going to be which side of the cross. I did think at first that maybe certain things were passed on based on sex but quickly that seemed to become clearly not the case. Still there has to be some process in how a breeder chooses which strains to cross and which gets to be the male and which the female. If as much work goes into it as has been stated it would seem kind of absurd for a breeder to not give some thought to it.

While relevent to the overall process all this talk of picking traits from F2's and such is really not as relevent to my question, except in what I think Tom was saying with regards to the Mexican/Afghani cross. It sounded like he was saying that since one strain had a higher instance of producing something along the lines of what his goal was (would produce more plants showing the favorable trait) that it was better to make it the Father. It sounded like he was saying by doing that it would increase the frequency of finding the desired combination from both strains in the F-2 stage. Or maybe frequency isn't the right word but it would make it easier to spot the desired combination of traits in the F-2 stage. If that's a correct understanding of what Tom was saying then it sounds to me like somebody in my situation would be well served by making things easier to spot and that while it might not matter in the way I first thought, it still matters which is male and which is female.

 

[softyellowlight]

It's mostly common sense. You pick a parent that passes on desirable dominant genes, or you pick a parent that passes on desirable recessive genes and backcross repeatedly until you get lucky with a stable line.

 

[HempKat]

It's mostly common sense. You pick a parent that passes on desirable dominant genes, or you pick a parent that passes on desirable recessive genes and backcross repeatedly until you get lucky with a stable line.

Well obviously you pick a parent with desirable traits either dominent or recessive. I mean is anyone going to pick a parent without desirable traits? What would motivate someone to try to cross plants that didn't have any desirable traits? Again I'm not asking how to pick strains to use or how to get to a finished marketable product. I'm asking once you have identified the strains you want to cross and found good candidates for passing on the qualities you wanted how do you decide which one gets to be mommy and which gets to be daddy or do you feel it doesn't matter?

 

[inquest]

I think the point Tom was trying to get across is that picking a male is more risky than picking a female. Therefore, you can minimize this risk by picking a male from a line that produces a higher percentage of high quality specimens, eg: an IBL. A hybrid line or a line that you are unfamiliar with should be the female.

Kinda like splitting 8's in BlackJack: Look around the table, if you see a bunch of high cards - split 'em, if not - let it ride!