Regular Seeds - Sex Predetermined or Mostly Determined?

[pop22]

I believe genetics determine sex. Anecdotal evidence suggests that sex can shift by environmental factors, however I've seen no science supporting this supposition.

I saw a good post on a Facebook group this morning and it was actually brought up here on AFN (back in 2011!)

But the question was this:

Is sex pre-determined in regular (non-feminized) cannabis seeds? If you plant a seed, is it the genetic code in that seed that says "this is a male" or "this is a female," or does environment factor into the equation (environmental stressors and variables causes genetic expression, ie, epigenetics?)

I've seen comments that heat mats will produce more females, that environment and lights can cause more females, etc. Smoke & mirrors? Voodoo-hoodoo?

What do YOU think?

 

[pop22]

There is nothing to support the theory that sex can be determined by the appearance of the seeds, its a myth.

I don’t what’s true. But, I’ve seen someone pick the sex 15 out of 15 seeds. After watching a YouTube video about it , we decided to try and experiment. Could be coincidence it was a first time experiment. He will try again in the spring.

 

[pop22]

The plant is still female. It has delveloped male sex organs and a species survival mechanism, that is triggered by hormones, the same way hormones are used in sex change procedures used by humans.

So when we say that plant sex can be altered by environment (like hermied, or technically pointed out to me today that it's become monoecious,) is that really changing the sex of the plant?

Is a female plant that hermied now male? Or is it a hermied plant? What's Bruce Jenner's actual sex as a human being? And does that differ than someone born genetically with both sets of parts?

(gotta throw a Bruce Jenner line in there somewhere)

 

[Ganjaholickz]

What goes on in our country for years and what I experienced myself is more acidic soil = more males. Just my 2cents ...

 

[RocBudInc]

Considering they have tests to tell u sex of a seed I would lean towards predetermined. I don’t know how accurate they are @RocBudInc uses the test I believe. I’ve read that hot soils cause more males I think it was @FullDuplex who came across this in his breeding. I wonder if ten seeds that tested female were started in a hot soil of any would “turn” male?

ive tested around a hundred seeds witht hose test and they are amazing!!! the only problem is that they are SUPER EXPENSIVE!!! even just doing say 10 plants thats 150 usd

 

[pop22]

And that survival switch is purely a hormonal response, the genetics don't change. The seed produced is all female the same as when you STS or CS spray a plant you are suppressing certain hormones to influence the development of pollen sacks. Its the exact same response. Plants don't change their sex, they merely adapt to prevailing conditions. I rather doubt that seedlings or immature plants have that ability prior to the preflower stage as the hormones are likely not present yet.

Well, that's not exactly true either,... Here's a couple examples: Peyote Purple, never offered as a fem' because this line is known for producing mostly females, and a local friends Lambsbread (from the home country confirmed, but clearly a hybrid, not a true landrace equatorial Sativa or it'd never finish where I live!); this one I have sent to several mates, 2 breeders and both struggled to get a good male to use for repro's and crosses...
The "stressed" mother in your example above, does not impart any bias toward sex ratio's, at least not that I've ever heard... The stress occurring with her at the time may make her toss nanners (in-bud male flowers) or if early enough, trigger full-on hermie male flowers found at the node junctions. It's pretty rare to see complete male flowers in a female bud, the nanners are called that because of they malformed male parts, but the stamen's can still make pollen,...
Otherwise, the various "hints" listed above, for whatever reason (if any other than just a quirk of physiology), are mitigating factors for shifting ratio's... Immaturity means sex hasn't manifested yet, and as you see there's a window in time that seems to be a strong influencer on this. It seems the plant can overcome it's "technical" sex.
** (this makes me think of crocodilians and egg T during incubation affecting sex ratios; here's a vertebrate who egg's can range from all female to all male between a certain temp range, with a mix showing in between.. Is sex set yet even in their case? Clearly not, but it begs the question that at the time of laying, are the eggs chromosomally sex determined, but capable of shifting? Turns out it is... this brief article can explain further if folks are interested. )
---> It must be something similar to this in cannabis... think genotypic sex vs. phenotypic sex.... Now, think about what's happening in a sex reversal on part of a female plant (not the entire plant) to get pollen for making fem's! Here we have all XX chromosome pollen,....

Mate, part of your answer is above,...and while the supposition that it's theoretically not possible to get males from fem' seeds, it's 100% wrong because it happens, rarely, but it does! Something else is in play here obviously, more complex than we are delving into here... As a biologist I can tell you that time and time again,. Mother Nature has work-arounds to her "rules"! ... A "genetic survival instinct", a "safety switch", whatever you call it, it's in regular operation out there... That lizard parthenogenesis I referred to, comes from an isolated population of lizards with no males... this trick occurs in a several other animal groups as well...

 

[Karr]

I saw a good post on a Facebook group this morning and it was actually brought up here on AFN (back in 2011!)

But the question was this:

Is sex pre-determined in regular (non-feminized) cannabis seeds? If you plant a seed, is it the genetic code in that seed that says "this is a male" or "this is a female," or does environment factor into the equation (environmental stressors and variables causes genetic expression, ie, epigenetics?)

I've seen comments that heat mats will produce more females, that environment and lights can cause more females, etc. Smoke & mirrors? Voodoo-hoodoo?

What do YOU think?

Sex is predetermined. Alot of things factor in though. For me I had all feminized autos and one hermied. Due to a stressful environment or it was trying to revive itself one last time. The seeds from it are all female. Heat stress, water levels and ph, nutes, heat, humidity can all change the sex of a feminized plant into a male

 

[GeorgeCloney]

Sex is predetermined. Alot of things factor in though. For me I had all feminized autos and one hermied. Due to a stressful environment or it was trying to revive itself one last time. The seeds from it are all female. Heat stress, water levels and ph, nutes, heat, humidity can all change the sex of a feminized plant into a male

Wait, Wait Dude!....we're splitting hairs here on this thread. So do you mean your plant ACTUALLY, turned male...
Or, do you really mean.....
The plant went from female to a hermaphrodite?
cause if it suddenly grew a (male chicken that rymes with rock).
We want a picture to post in the Smithsonian

 

[The_Skunkist]

From my experience :
I used to have few regseeds pack 100% female with severals factors . Luck ? I don't think so .
Superior N level ( wormcast +coco can be enough depending on wormcast npk ), white light,light cycle, nice humidity level, right temp with cold tendecy ( more 21° than 26°) .

+ I have seen another phenomena on young autos . Undetermined sex organs . Not male, not female . Generally they finish dried .
A little round ball without pollen and without pistils .And if you throw them as hermies .. you are not doing the right move .

Dried air place and hot temps and hydric stress are the top conditions to get hermies from feminized seeds .
You can make wonderfull stuff heating the roots too ...
Last year was severe with confirmed heat records around my place .

 

[Anthropolis]

I'm with most on this: yeah, pretty sure the code in the seed is predetermined, but can be pressured to switch under extreme stressors. Just like with herms.

Specifically I think it's determined when the pollen fertilizes the flower successfully, the genes are combined, and it begins to make the seed. One cool science-ey thing that would be an epic advancement is if we had a method of knowing, at pollinaiton time, if that calyx was going to create a male or fem seed.