What's new
  • As of today ICMag has his own Discord server. In this Discord server you can chat, talk with eachother, listen to music, share stories and pictures...and much more. Join now and let's grow together! Join ICMag Discord here! More details in this thread here: here.

Basic genetics explained

VerdantGreen

Genetics Facilitator
Boutique Breeder
Mentor
ICMag Donor
Veteran
i understand sam, breeding with limited space and numbers is less than ideal - but then thats all some of us have, and i dont know anyone who is going to be kind enough to try and back up my favorite genetics for me in seed form (clones are fine as long as you are in a position to keep them - but i may well not always be)

so i will go ahead and try to do the best i can with the resources that i have. I understand that some will resent that and think it is irresponsible - but as the probable alternative is that one day i may have no plants and no seeds of them as back-up, i'll continue to defy the advice from authority - just as i did when i decided to try smoking cannabis ;)

thanks for your time :tiphat:, we are truly blessed to have you contributing here, long may it continue
sincerely
VG
 

KiefSweat

Member
Veteran
Sam, whats your thought on males that pop up in self-fertilized lots? I've heard from a few people who have grown decent enough populations that this can happen and that they may even be useful in further breeding.
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
Sam, whats your thought on males that pop up in self-fertilized lots? I've heard from a few people who have grown decent enough populations that this can happen and that they may even be useful in further breeding.

Do you mean a male that pops up in all female seed?
A selfed means only one plant was involved, one a female and the other same clonet a female induced to be male.
When people are making all female seed they are masculating a female and then using the pollen to make the seeds normally on a different varieties female/clone. People do self clones but seldom, as it leads to a loss of vigor and all kinds of negative recessive traits expressing that you do not want.
If a male pops up in a all female population either there was a pollen error or one of the two plants used has intersex genes/traits.
I would not use it, except as an experiment.
-SamS
 

KiefSweat

Member
Veteran
from what I've seen they have been in "fem" lines. It seems to pop up in a some s1/s2s of bubba and a few other plants. I think the peyote purple had one generation that was almost 90% male. I don't know about hybrids using reversed pollen in that regards it seems to have been on inbred lines.

They say with feral hemp crops that they will revert back to normal sexual ratios after a few generations as well, mathematically it seems possible to do with intersexed plants if your breeding for that trait, unless i'm completely off base with that.
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
I've seen this stated several times regarding monoecious hemp as well (could be that everyone is simply citing the original publication on monoecious hemp breeding by von Sengbusch). Basically, monoecious hemp breeding is the same like dioecious breeding just that you do the opposite and select for female 'hermies' and cull the males. There's no biological possibility allowing such a variety to 're-convert' to the dioecious origin. It may be stray pollen (most likely IMO) or, because in hemp breeding one deals with thousands of individuals and not miss a single unwanted plant is nearly impossible, that by coincidence a very few male 'hermies' have been mistaken for monoecious females. Because males usually flower before the females, it's inevitable that they take over after a few generations.

How, apart from stray pollen, it could be possible to find true males in a clone only (pure female) variety I do not know. Maybe just a female gone 'full hermie' or the original female was indeed a 'full hermied' male (which would explain the >90% males in the offspring)?
 

VerdantGreen

Genetics Facilitator
Boutique Breeder
Mentor
ICMag Donor
Veteran
i think the peyote purple is an S2 of the Katsu bubba cut, and does indeed have 'ladyboy' type males quite commonly.

not sure what relation the katsu cut is to the pre-98 bubba cut (if any), but ive made and sold loads of pre-98 bubba S1s without a single report of any intersex traits in the progeny.

VG
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
I've seen this stated several times regarding monoecious hemp as well (could be that everyone is simply citing the original publication on monoecious hemp breeding by von Sengbusch). Basically, monoecious hemp breeding is the same like dioecious breeding just that you do the opposite and select for female 'hermies' and cull the males. There's no biological possibility allowing such a variety to 're-convert' to the dioecious origin. It may be stray pollen (most likely IMO) or, because in hemp breeding one deals with thousands of individuals and not miss a single unwanted plant is nearly impossible, that by coincidence a very few male 'hermies' have been mistaken for monoecious females. Because males usually flower before the females, it's inevitable that they take over after a few generations.

How, apart from stray pollen, it could be possible to find true males in a clone only (pure female) variety I do not know. Maybe just a female gone 'full hermie' or the original female was indeed a 'full hermied' male (which would explain the >90% males in the offspring)?

Mononecious reverts to dioecious quickly,
I have had this told to me by every hemp breeder I have talked to from Dr Bocsa to the Ukrainians and french breeders J.P. Mathieu, et al. and the Polish and others that maintain monoecious varieties. I know them all.
http://www.internationalhempassociation.org/jiha/iha01215.html

IBocsa: The natural state in which hemp appears was and is dioecious. Monoeciousness is artificial in hemp, it can only exist with the help of man, and without selection, the dioecious state will return in two or three generations. It is therefore very hard and demanding to keep 90 to 95 % monoeciousness during seed multiplications. Apart from that, however, monoecious hemp is appropriate only when the crop is grown for so-called double use, i.e. when both stem and seed are harvested. This is the case in France and in the former Soviet Union, where most crops are grown for double use. In a dioecious crop, the male plants will be strongly deteriorated when the crop is harvested at seed ripeness, so in this case one needs monoecious cultivars. In Hungary and its neighbouring countries, like formerly in Italy, this double use is unknown. Here fibre hemp is grown as a dense crop which is harvested at the time of male flowering ("green hemp"), while seed production takes place in crops grown at a low plant density and with completely different growing techniques. For this 'classic' use monoecious cultivars are of no use, so we never bred a monoecious cultivar.

Furthermore, monoeciousness has two large disadvantages. In the first place, all monoecious cultivars which I tested over the last 20 to 25 years yielded 10 to 20 % less than dioecious cultivars. This is caused by the possibility of self-pollination and the resulting inbreeding. With model experiments and with biometric determinations we have established that 20-25 % of self-pollination takes place in monoecious hemp, and this is the cause of the lower stem yield. In the second place, in monoecious hemp, the genetic progress for fibre content is slow, because the so-called Bredemann principle can not be used. The Bredemann principle consists of the rapid determination of fibre content in male plants before they flower, so that only the males with the highest fibre content are allowed to pollinate the female plants. In a breeding garden (nursery) of one hectare, I have 15,000 to 20,000 plants and I need only the very best 50 to 100 males for the pollination. (This can be compared to breeding of dairy cows, where a few hundred extremely good bulls inseminate all the cows of an entire country.) In monoecious hemp this approach can not be used, so the rate of genetic progress is only 50 % or less of that in dioecious hemp. In spite of these disadvantages, we use a monoecious hemp cultivar in breeding, but only as a parent for unisexual hemp.

About Monoecious:

Cultivars from France are bred and commercialized by the Fédération Nationale des Producteurs de Chanvre (FNPC), 20, rue Paul Ligneul, F-72000, Le Mans, France; Fax: +33 4377 0916. French cultivars are monoecious. In France they are grown for pulp. Their cultivation within the EU is eligible for the subsidy on fibre crops. Current breeding in France is mainly aimed at maintenance of the present cultivars (conservative breeding) and at further reduction of their THC content. Seed for sowing is readily available in two qualities. Crops grown from first quality seed (elite seed) consist almost exclusively of monoecious plants. Those from second quality seed (harvested from free-pollinated crops raised from elite seed) comprise, due to natural genetic drift, 15 to 30% males as well as a substantial amount of true-female plants.

What you can see is that quickly the monoecious is replaced by dioecious males and that just speeds the process. In one year free pollinating 15 to 30% males already. They also said to maintain their elite monoecious lines they only use monoecious individuals with the right ratio and placement of male to female flowers, as well as habit, males can have a female habit, or male habit. Females can have a male habit, that is they look more like a real loose stringy male in silhouette, or female habit with big thick flowers.

-SamS
 

KiefSweat

Member
Veteran
I've seen this stated several times regarding monoecious hemp as well (could be that everyone is simply citing the original publication on monoecious hemp breeding by von Sengbusch). Basically, monoecious hemp breeding is the same like dioecious breeding just that you do the opposite and select for female 'hermies' and cull the males. There's no biological possibility allowing such a variety to 're-convert' to the dioecious origin. It may be stray pollen (most likely IMO) or, because in hemp breeding one deals with thousands of individuals and not miss a single unwanted plant is nearly impossible, that by coincidence a very few male 'hermies' have been mistaken for monoecious females. Because males usually flower before the females, it's inevitable that they take over after a few generations.

How, apart from stray pollen, it could be possible to find true males in a clone only (pure female) variety I do not know. Maybe just a female gone 'full hermie' or the original female was indeed a 'full hermied' male (which would explain the >90% males in the offspring)?

Sengbusch did grow thousands of plants tho. Bosca may have expanded a bit on the theory in his book as well.

If a plant was a "true" xx female wouldn't it be sterile or not be able to produce male flowers? If the plant can self pollinate it self i would assume there is a y autosome somewhere in there and that changes the population genetics of the offspring
 

mofeta

Member
Veteran
People do self clones but seldom, as it leads to a loss of vigor and all kinds of negative recessive traits expressing that you do not want.
-SamS

There is an old IT saying, "That's not a bug, that's a feature!".

Deleterious recessive traits can only be culled if they are visible, only if they are expressed. The same population that produces individuals homozygous for deleterious traits will also produce individuals homozygous for desired traits. You just have to sort them out (to me the most challenging obstacle in breeding is the evaluation of individuals for selective purposes, must develop good machine testing).

When I have discussed this with Tom (he is a big proponent of this) I likened it to "breeding weed like it was tomatoes", in other words, treating it like an incrosser, and he agreed that that was his strategy. This requires proper numbers, of course, but I don't think that is a consideration with you?

There is a loss of vigor that is unavoidable with this technique, but is easily mitigated by running several parallel lines derived from the S1, or parallel selfed lines from 2 or more similar clones. Once you have a few parallel lines that are homozygous (for the most part) for the stuff you want, but kinda wimpy vigor-wise, you just cross the lines up. You end up with batches of seed that can be used for production, that produce crops with clone-like homogeneity expressing the desired traits.

Of course the vigor is not as impressive as that seen with wider crosses, but how much vigor do you need? I more concerned with having the exact specific effects I am looking for in a plant, and consistency, than I am with ease of growth.
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
There is an old IT saying, "That's not a bug, that's a feature!".

Deleterious recessive traits can only be culled if they are visible, only if they are expressed. The same population that produces individuals homozygous for deleterious traits will also produce individuals homozygous for desired traits. You just have to sort them out (to me the most challenging obstacle in breeding is the evaluation of individuals for selective purposes, must develop good machine testing).

When I have discussed this with Tom (he is a big proponent of this) I likened it to "breeding weed like it was tomatoes", in other words, treating it like an incrosser, and he agreed that that was his strategy. This requires proper numbers, of course, but I don't think that is a consideration with you?

There is a loss of vigor that is unavoidable with this technique, but is easily mitigated by running several parallel lines derived from the S1, or parallel selfed lines from 2 or more similar clones. Once you have a few parallel lines that are homozygous (for the most part) for the stuff you want, but kinda wimpy vigor-wise, you just cross the lines up. You end up with batches of seed that can be used for production, that produce crops with clone-like homogeneity expressing the desired traits.

Of course the vigor is not as impressive as that seen with wider crosses, but how much vigor do you need? I more concerned with having the exact specific effects I am looking for in a plant, and consistency, than I am with ease of growth.

That is what was done for the single Cannabinoid varieties, 4 lines as different as can be varieties selfed several generations and at the end two were combined from the four, and also the other two combined, and then the two combos were combined, it worked. I do prefer vigorous plants, and do not want un-vigorous plants.
-SamS
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
Mononecious reverts to dioecious quickly,
I have had this told to me by every hemp breeder I have talked to from Dr Bocsa to the Ukrainians and french breeders J.P. Mathieu, et al. and the Polish and others that maintain monoecious varieties. I know them all.
...
Those from second quality seed (harvested from free-pollinated crops raised from elite seed) comprise, due to natural genetic drift, 15 to 30% males as well as a substantial amount of true-female plants.
...
-SamS
Thank you for the clarification! I just wasn't sure if this is something like the spinach story where everyone for the last 50 years copied from the first (who mad a bad mistake).

Genetic drift? I don't think that simple genetic drift suffices to turn an X allosome into a Y. As said, if it's not stray pollen, I can't explain it... I you happen to have an idea, I'm all yours!

Sengbusch did grow thousands of plants tho. Bosca may have expanded a bit on the theory in his book as well.

If a plant was a "true" xx female wouldn't it be sterile or not be able to produce male flowers? If the plant can self pollinate it self i would assume there is a y autosome somewhere in there and that changes the population genetics of the offspring
Females are always XX... The X allosome does not 'produce' female flowers, nor does the Y 'produce' male ones; they just regulate genes on the heterosomes which in turn lead to female or male flower production, respectively. AFAIK it's like that with most species and one reason why 'phenotypical sex inversion' is possible.
 

mofeta

Member
Veteran
I do prefer vigorous plants, and do not want un-vigorous plants.
-SamS


Me too. But it is not at the top of my list, effect and consistency are. Ideally, I would maintain lines specifically for general vigor, pest resitance, cultural traits and so forth, with as little taste/smell and a bland high (but lots of resin) and then introgress the stuff I want from my homozygous incrossed lines for the best of both worlds.

That would require employees and such though, so I will have to wait until the legal climate here improves a bit more. I think within the next 5 years.
 

KiefSweat

Member
Veteran
how many generations do you need to go to start seeing vigor loss and depression?
I can see with hemp lines how in one generation you could see a loss of vigor but if your starting with a polyhybrid drug strain the outcomes might be different.
 

KiefSweat

Member
Veteran
Females are always XX... The X allosome does not 'produce' female flowers, nor does the Y 'produce' male ones; they just regulate genes on the heterosomes which in turn lead to female or male flower production, respectively. AFAIK it's like that with most species and one reason why 'phenotypical sex inversion' is possible.

I thought the Y chromosome was necessary for proper pollen development.
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
how many generations do you need to go to start seeing vigor loss and depression?
I can see with hemp lines how in one generation you could see a loss of vigor but if your starting with a polyhybrid drug strain the outcomes might be different.

If you self anything 3 or more you have serious problems with pollen being functionally sterile as well as many more problems.
The problem with selfing a polyhybrid is the selfed will not resemble the parent at al and it will lose vigor.
-SamS
 

Only Ornamental

Spiritually inspired agnostic mad scientist
Veteran
I thought the Y chromosome was necessary for proper pollen development.
How would you explain that STS reverts phenotypical sex and that one can breed with such pollen?
I'm not saying that the viability is the same (I don't know)...
I've seen males being 'halfway female' in that they produce male flowers with pistils and anthers; these were always sterile and did not react to STS (but I haven't done this experiment very properly). Unfortunately, I have no access to ethephon to play around.
 

KiefSweat

Member
Veteran
there are degrees of inter-sexed plants that are going to be effected by the environment.

The research that Sengsbusch and Bosca did concluded there are only 1-2% true females or males. I know there are a few clones that when reversed don't seem to drop pollen or set seed, but it seems like 95% on the other hand do. I would assume those are 1st degree herms that you only see with stress, and normally wouldn't see unless the plant was overripe.

Sam encountered herm lines that he worked out so its not far fretched that others released lines that still have that problem, if they looked like the sex they should be and where never stress tested you might never know until down the line, I also believe that the Indians used pull the males but leave intersex plants in the field with to make seeds with, the British wrote an account of it in the late 1800s if I recall
 

Sam_Skunkman

"RESIN BREEDER"
Moderator
Veteran
there are degrees of inter-sexed plants that are going to be effected by the environment.

The research that Sengsbusch and Bosca did concluded there are only 1-2% true females or males. I know there are a few clones that when reversed don't seem to drop pollen or set seed, but it seems like 95% on the other hand do. I would assume those are 1st degree herms that you only see with stress, and normally wouldn't see unless the plant was overripe.

Sam encountered herm lines that he worked out so its not far fretched that others released lines that still have that problem, if they looked like the sex they should be and where never stress tested you might never know until down the line, I also believe that the Indians used pull the males but leave intersex plants in the field with to make seeds with, the British wrote an account of it in the late 1800s if I recall

In india the sinsi Ganja farmers had Poddars (Ganja Doctors) that walked through the fields at the very beginning of flowering and removed all males and all intersex, they were the first to understand what was really going on with sinsi.
If you read the Indian Hemp Commission Report of 1894, 8 Vols over 3500 pages long with testimony from almost 1,200 "doctors, coolies, yogis, fakirs, heads of lunatic asylums, bhang peasants, tax gatherers, smugglers, army officers, hemp dealers, ganja palace operators and the clergy. You get an idea how well some understood Cannabis.
http://digital.nls.uk/indiapapers/browse/pageturner.cfm?id=74908458
I have read it all, I have original copies of several vols, reprints of them all.

-SamS
 

Latest posts

Latest posts

Top