The determinator of sex

[auto guerilla]

you cant have XXY because they only hold dominant and recessive genes. what i want to know is 'what is the key to fertility'? such as males and hermaphrodites that don't produce pollen. that's what I want to know.

 

[browntrout]

Lol You guys are some funny. I'll stick with my own opinions I guess, Kinda knew I wouldn't change them anyhow.

 

[xmobotx]

this isnt going to be an opinion thing

probably sooner rather than later we will understand this unless the gov goes totally fascist/likely there are already some learned people who do totally understand it

it would seem that in different instances; the herm trait passes and/or presents for different reasons ~maybe it has to do w/ epistasis ~and likely environ is a big factor albeit secondary to genetics

nonetheless as it proves out it will prove to be science and not opinion

 

[Infinitesimal]

you cant have XXY because they only hold dominant and recessive genes. what i want to know is 'what is the key to fertility'? such as males and hermaphrodites that don't produce pollen. that's what I want to know.

first,
dominant and recessive? we are talking about the sex of the plant not dominant and recessive traits.

to answer your question...
hermaphrodites that cannot self pollinate, are the evolutionary link between the wild monoecious cannabis and the dioecious two sex cannabis of today... a herm (remember monoecious so all plants were herms) that has active pollen and sterile female bracts can only pollinate a separate plant... if it found another herm with fertile female bracts and sterile pollen... then the first male x female cross was made... over the course of generations and selective pressures we end up with our two sex male and female cannabis plants... that is the key to fertility and why some herms and males don't produce pollen... also it could be a genetic or environmental problem... like men with a low sperm count or sterile men... it just happens sometimes... genetics is sort of a lotto... or it could be from an XXY syndrome that a male or herm has sterile pollen as the condition does effect sex hormones

secondly,
you are wrong about the XXY thing...

http://medical-dictionary.thefreedictionary.com/polyploid

polyploid
[pol′əploid]
Etymology: Gk, polys + plous, times
1 n, an individual, organism, strain, or cell that has more than twice the haploid number of chromosomes characteristic of the species. The multiple of the haploid number is denoted by the appropriate prefix, as in triploid, tetraploid, pentaploid, hexaploid, heptaploid, octaploid, and so on. Polyploidy is rare in animals, producing individuals that are abnormal in appearance and usually infertile. It is common in plants, however; such plants generally are larger, have larger cells, and are hardier than diploid plants. (just speculating here, but what if by people selecting for big vigorous males plants they are unknowingly selecting these polyploidic males that may be more likely to pass on hermaphroditic and inter sex traits???)
2 adj, also called polyploidic. Pertaining to such an individual, organism, strain, or cell. Compare aneuploid. polyploidy, n.
Mosby's Medical Dictionary, 8th edition. © 2009, Elsevier.



-because cannabis is the only dioecious annual plant in the kingdom, I didn't readily find any info related to the sex chromosomes in plants, but since polyploidy is more common in plants than animals... one can assume the same goes for cannabis' sex chromosomes



http://www.ncbi.nlm.nih.gov/pubmed/2630188

Analysis of the sex-chromosome constitution of digynic triploid mouse embryos.
Speirs S, Kaufman MH.
Source
Department of Anatomy, Medical School, Edinburgh, UK.
Abstract
LT/Sv strain mice regularly ovulate up to 50% of their eggs as primary oocytes, which are fertilisable and give rise to digynic triploid embryos. A similar number of eggs are ovulated as secondary oocytes and, following fertilisation, give rise to normal diploid embryos. Pregnant LT/Sv females were autopsied at about midday on day 10 of gestation, when normal diploid embryos would be expected to possess between 25 and 30 pairs of somites.

While a few of the triploid embryos either consisted of disorganised embryonic masses or were resorbing, most were at readily recognisable embryonic stages. Just over half of the embryos recovered were "unturned," while the remainder had "turned" and possessed between 15 and 25 pairs of somites.

The triploids were usually readily recognised, owing to their small size and because they often displayed neural tube and cardiac defects. All of the embryos recovered were analysed cytogenetically by G-banding to establish their ploidy and sex-chromosome constitution. The XY:XX sex ratio of the 105 diploid embryos recovered, all of which had "turned," was 1.06:1, while the overall XXY:XXX sex ratio of the 120 triploids was 1:1. Analysis of only the developmentally most advanced triploid embryos (i.e., the 49 that had "turned") revealed that the XXY:XXX sex ratio in this group was 1.13:1, which was not significantly different from the expected ratio of 1:1. The crown-rump lengths of the XY and XX "turned" embryos were almost identical, as were those of the XXY and XXX "turned" embryos, although the triploids were significantly smaller than the diploids.

No obvious effect of sex-chromosome constitution on developmental potential was therefore observed in this study in relation to either the digynic triploid or the control diploid embryos.




several polyploidic syndromes in humans (for which it is more rare than in plants)

http://en.wikipedia.org/wiki/Klinefelter's_syndrome -- XXY Syndrome...

http://en.wikipedia.org/wiki/XYY_syndrome -- XYY Syndrome...

http://en.wikipedia.org/wiki/Triple_X_syndrome -- XXX Syndrome...

again these are human syndromes... but remember polyploidy is much much more rare in animals so there is no doubt this type of thing is happening with the genes that control sex in cannabis.

Lol You guys are some funny. I'll stick with my own opinions I guess, Kinda knew I wouldn't change them anyhow.

well that is very wise and open minded of you isn't it... Opinion, never mind evidence and fact, all of the most intelligent people in history have always intuitionally known what was right and what was wrong... right?

 

[Infinitesimal]

So are you saying the males from Charlies peyote purple are really girls?

I couldn't say... maybe when selecting offspring to reverse while breeding... he selected a "female" that was actually a XXY male?

which may explain the low penetrance of the males in the PP line... if a "sissy" XXY male, expressing female gender traits, was used... this is just speculation, though plausible I think.

 

[Infinitesimal]

its X/Y + autosomes
and wheter its also a thing in the PAR region of the X or Y is still debatable.

one could wery well think that the mecanisms that trigger the expression of the autosomal things may lay in the PAR region of the X and Y. there are reported some instances of crossovers between X and Y in these regions in the offspring.

if you are talking about herms...

it's more like Genetics + Epigenetics... environment can trigger chemical tags to activate, disrupt or silence gene expression/function.


http://www.sigmaaldrich.com/life-science/epigenetics.html

Epigenetics
Epigenetics describes changes that are stable, but potentially reversible alterations in gene expression, that occur without permanent changes in DNA sequence and can still be passed on from generation to generation. Epigenetically controlled genes are activated or repressed without any change in DNA. Sigma® has a wide portfolio of products to support Epigenetics research.



http://www.merriam-webster.com/dictionary/epigenetics
epigenetics



epi·ge·net·ics noun \ˌe-pə-jə-ˈne-tiks\

Definition of EPIGENETICS

: the study of heritable changes in gene function that do not involve changes in DNA sequence

First Known Use of EPIGENETICS

1942
epi·ge·net·ics noun plural but singular in construction \-iks\ (Medical Dictionary)

Medical Definition of EPIGENETICS

: the study of how genes produce their effect on the phenotype of the organism


epigenetics (Concise Encyclopedia)
The study of the chemical modification of specific genes or gene-associated proteins of an organism. Epigenetic modifications define how genetic information is read and used by cells. Epigenetic modifications can be inherited and are influenced by environmental factors, some of which can induce epigenetic signaling that may contribute to biological processes such as aging. Methylation is the principal epigenetic modification of deoxyribonucleic acid (DNA) and of proteins called histones that package DNA into chromatin inside a cell. Epigenetic modifications influence gene expression and enable the differentiation of pluripotent stem cells (cells with the potential to become any of many different kinds of cells) into distinct cell types early in embryological development. The ability to control and alter stem cell differentiation through the manipulation of epigenetic modifications has profound implications for the treatment of conditions such as neurodegenerative disease.

 

[Tonygreen]

Too many pages without a pic. Determine sex please.

 

[GMT]

lol Tony, sex only really matters when breeding. If you were out on the pull, and saw someone with big tits and a beard, would you think, I hope that's female, or just keep walking?

 

[xmobotx]

clearly he has a problem distinguishing and wouldnt even notice

j/k tony ~too funny to pass up

 

[Infinitesimal]

The Determinators of Sex?​

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Three main factors that determine sex....
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[Infinitesimal]

Too many pages without a pic. Determine sex please.

[URL=https://www.icmag.com/ic/picture.php?albumid=42494&pictureid=1068531&thumb=5]View Image[/url]

 

[FoCo(No.Co)]

You must spread some Reputation around before giving it to Infinitesimal again.

guys do yourselves a favor and try this experiment. foliar feed all your regular seedlings with kelp extract, every 3 days, with a plain water spray in between. I bet 90%-100% of them will turn out female.

I bet not.

 

[auto guerilla]

thankyou infinitesimal for your reply. i have had many troubles with sterile males coming from regular seed stock. You have pointed me in the right direction of what i'm looking for. I hope i find the answer to bringing fertility to my favourite strain. I don't know if it's an environmental or genetic factor though. Further help appreciated.

 

[Jack Harer]

I'm still of the belief that environment and pheromones play an active roll in sexual expression.
I germed and vegged 50 plants from seed (changing up the room genetics) and got over 45 males from that batch. Certainly not the 50/50 ratio one would think. After examining all other factors and discarding them, I figured that it was due to the close proximity of a whole room full of females that caused the imbalance.
I repeated the experiment and germed 50 more. Same results, almost 95% males. I do not have the luxury of keeping a room full of males to check it that way, but I believe that if a seedling/young plant develops in a field of mostly females, it willl become a male, and vice versa.
We know that a female will throw pollen sacs at the end of her lirecycleto ensure the continuity, why can't this be so as well?
IMHO, sex isn't fully determined until about the third or fourth node. Just my 2 cents and observation.

 

[GMT]

Auto, lower your room humidity.
Jack, nope you're wrong sorry.

 

[BullDogUK]

Infini, I agree that cannabis sex is determined by an XX/XY over an XX/X- mechanism but I don't think anyone understands cannabis epigenetics enough to confidently say that silencing of the Y chromosome does not occur given certain environmental conditions.

Similarly are you privy to the locus of genes involved in the production of male-associated proteins? Frankly we don't even know if they are located on the Y-chromosome. It seems likely but equally, the 'male' chromosome may simply be one giant promoter region that manages the expression of genes resulting in a male sex.

Edit: As you say, Cannabis has evolved from a monoecious ancestor. I'm not convinced that this evolution of dioecy is exactly the same followed by 'animal' species so to assume that similar mechanisms are followed is a bit of a leap of faith for me.

 

[xmobotx]

well i would have culled what i thought was going to be the 3rd herm in the F1 progeny of my cross but decided {as i have 1 fem seeded @ this point by the other herm} 'why not have 2 lines of F2s to work w/"

last night i observed that there are no pistillate flowers emerging thus far

FTR; that is 3 out of 12 @ this point which werent female & this is a 'natural' herm pollen donor not a stressed plant for this project

we shall see i guess/there is zero possibility for confusion here

 

[Infinitesimal]

Too many pages without a pic. Determine sex please.

[URL=https://www.icmag.com/ic/picture.php?albumid=42494&pictureid=1068531&thumb=5]View Image[/url]

that plant is most likely a genetic herm... mosaic genetics... two differing cell lines in one individual... both XX and XY (karyotype XX/XY) are in different cells within the organism. so the plant ends up with both male parts and female parts scattered about ( it is possible that if one cell line out competes the other and the organism is a vast majority of one sex or the other... the sex that makes up the minority may be hormonally retarded and not express its self correctly/or at all)

Infini, I agree that cannabis sex is determined by an XX/XY over an XX/X- mechanism but I don't think anyone understands cannabis epigenetics enough to confidently say that silencing of the Y chromosome does not occur given certain environmental conditions.

Similarly are you privy to the locus of genes involved in the production of male-associated proteins? Frankly we don't even know if they are located on the Y-chromosome. It seems likely but equally, the 'male' chromosome may simply be one giant promoter region that manages the expression of genes resulting in a male sex.

Edit: As you say, Cannabis has evolved from a monoecious ancestor. I'm not convinced that this evolution of dioecy is exactly the same followed by 'animal' species so to assume that similar mechanisms are followed is a bit of a leap of faith for me.

good post bulldogUK.... I'll try an see if I can get Chimera in here... he has been lab testing and doing genetic analysis on cannabis for a little while now... I don't know if they have mapped karyotypes yet ,though I would imagine so... in which case he should be able to clear this up pretty easily.

my feelings on the evolution of dioecy are that...
1 it is primarily an animal function... so that it is in plants at all says something... never the less a plant so tied to intimately to humans

2. humans were integral in the evolution of cannabis (read/watch botany of desire) and since we have such a long intimate relationship with the plant I can imagine why the plant has evolved such similarity and shared such synergy with the human race (plenty of bugs, crabs and such... that have evolved patterns that resemble human faces... because people wouldnt kill/eat ones that looked like they had faces on them... so the ones with faces bred with ones with faces and now the species have faces on them... we humans like to shape things in our own image)... is it any wonder that a plant species can go from one that is a wild, non psychoactive, monoecious, fiber/seed producing plant... with 5k+ years of shared environment resources and life with humans... ends up sharing so many "human" (THC, recombinant genetics etc etc) characteristics

 

[CFP65]

it would be wery nice if the anti-autosome contingent would come up with some coherent thing in favour for thier statements

 

[DemonPigeon]

I'm still of the belief that environment and pheromones play an active roll in sexual expression.
I germed and vegged 50 plants from seed (changing up the room genetics) and got over 45 males from that batch. Certainly not the 50/50 ratio one would think. After examining all other factors and discarding them, I figured that it was due to the close proximity of a whole room full of females that caused the imbalance.
I repeated the experiment and germed 50 more. Same results, almost 95% males. I do not have the luxury of keeping a room full of males to check it that way, but I believe that if a seedling/young plant develops in a field of mostly females, it willl become a male, and vice versa.
We know that a female will throw pollen sacs at the end of her lirecycleto ensure the continuity, why can't this be so as well?
IMHO, sex isn't fully determined until about the third or fourth node. Just my 2 cents and observation.

"Females" which throw pollen late stage are doing this because it's a strategy which works, in grow rooms all accross the world males are culled but often a small amount of staminate flowers won't be noticed until they hit the females in the well lit, well ventilated room. It produces seeds, those seeds are planted and each may carry the chance of reproducing exactly the same way.

the female itsn't throwing pollen due to some communication with the other plants and an awareness of the scarcity of males, though it has been stated (Marijuana Botany) that the odds are lower if the plant has aready been seeded.
The way that those plants "detect" the absence of males is simply a failure to be pollinated triggering a gene that functions to "rectify" that situation. other strains just do it regardless because it works.

I will say the genetics for male expression must be carried in each female or how would Silver treatments work?

But the idea that plants designate gender based on pheremones doesn't really make sence.

Also 45/50 plants twice doesn't seem too ridiculous a figure to be explained by mere probability, if a morrocan hash farmer got that breakdown over 5 acres of crop in consecutive years I'd have to reconsider my position but really maths could fit your experience into the norm.
Or it could be something with the seeds themselves, maybe you accidentally ordered "masculinised seeds"