More Females out of Seed

a good trick is buying good quality feminized seeds...

^LOL. Yeah, I think 70% is the best you can hope for, without going to feminized seeds. I'm pretty sure there's already been thousands of hours of experimenting done, seeking the same answers that you are, with no consistent results getting a much higher 'female/male ratio' than what you're getting.

crack on son! we would all like that i think...

welshsmoker said:

crack on son! we would all like that i think...

Click to expand...

Clones here, nothing but clones....100% everytime

jesus of Cannabis said:

Clones here, nothing but clones....100% everytime

Click to expand...

agree with you on that, but when your stuck....

there is a lot of bs in books and forums about this. There is nothing you can do to affect sex. The sex is predetermined in the seed. If you want to grow more females from seed, buy feminized seeds.

HOW TO ALTER THE PERCENTAGE OF FEMALES

From literature it appears that the growth of a male or female plant from seed, except for the predisposition in the gender chromosomes, also depends on various environmental factors. For growers who are well experienced, percentage of female plants is 60% - 90% female, but less experienced growers can end up with 100% male plants. The environmental factors that, according to literature, influence gender are:

- a higher nitrogen concentration will give more females (at the three-pairs-of-leaves stage and continue for two or three weeks).

- a higher potassium concentration will give more males (at the three-pairs-of-leaves stage and continue for two or three weeks).

- a higher humidity will give more females (at the three-pairs-of-leaves stage and continue for two or three weeks).

- a lower temperature will give more females (at the three-pairs-of-leaves stage and continue for two or three weeks).

- more blue light will give more females (at the three-pairs-of-leaves stage and continue for two or three weeks).

- Fewer hours of light will give more females (at the three-pairs-of-leaves stage and continue for two or three weeks).

- In later stage, as you increase the light, the plants grow faster and show more females/less males.

Sixteen hours of light per day seems to be the best combination, beyond this makes little or no appreciable difference in the plant quality.

- Another idea is to interrupt the night cycle with about one hour of light, This gives you more females.

- Spray dilute Fish Emulsion ( 1 tablespoon per gallon ). When the plants have three sets of true leaves, plus the top sprout, give them a wetting spray of Fish Emulsion. Do it once a day for three of four days. Top and bottom of the leaves.

- To achieve 100% female plants is to expose young seedlings for several hours to an atmosphere of Carbon Monoxide. It doesn't hurt the plants, but it could kill you.

- Treatment of hempseed with ethylene gas will increase the resulting number of female plants by about 50%. Ethylene is produced by certain plants (i.e., bananas, cucumbers and melons), and these can be used to treat hempseed in a simple manner. About two weeks before you plan to sprout the seeds, place them in a paper bag or envelope and put that in a plastic bag with the peels of a ripening banana or cucumber.

Replace the peels after a couple of days, and change the bags to prevent mold.

- When hempseed is treated with the female hormone estrogen, percentage of females that are produced will increase by about 10%.

Dissolve a birth control pill in water and soak the seeds overnight in the solution. After the initial soaking, continue to treat the seeds by sprouting them on a paper towel soaked in the solution.

courtesy of cannabis-seed-banks.com[/COLOR][/I]

Great info Jesus! Birth control though, really? That is a new one most definitely. I am running near 80% humidity, about 60-65 degrees with a slight breeze, under a 200w CFL, with everything on heating mat. Right now I have 6 seedlings and 2 clones going and they are loving it, this will be my 2nd grow and I expect my results to be that of a 3rd time grower. I'll try and post updates as 3 of the seedlings are starting to get their 3rd set of leafs.

I have read ALL the Old Wives´ Tales about turning your plants female - all a load of baloney.

This is why we pay extra for feminized seeds.

TelecomJunkee said:

Great info Jesus! Birth control though, really? That is a new one most definitely.

Click to expand...

Did you know the word GULLIBLE isn´t in the dictionary??

No offense, but the word optimistic must not be in your dictionary. I just found this piece of info which just so happens to be exactly what I have been doing accidentally from the start. "A Russian study showed that seedlings with at least 4 inches of soil to grow the tap root were more likely to go female. The source I'm quoting says This may be why some farmers get female/male ratios as great as 80/20.", I am batting about .750 currently. Here are some updated pics of the 4 week old kids. Low temps(62-70), High Humidity, reduced hours of daylight(15-9)

I'm not saying this to be mean, but I want to see some evidence of all these claims. Saying their was a study in russia on this doesnt mean much w/o some evidence from others backing it up, if its true then others should easily be able to replicate the results and prove or disprove it, if it cant stand up to that then it must not be true. So can anyone here back up the claims with controlled side by side experiments with more than one source? I would love to see them. Again, no offense to anyone meant.

darkdestruction420 said:

I'm not saying this to be mean, but I want to see some evidence of all these claims. Saying their was a study in russia on this doesnt mean much w/o some evidence from others backing it up, if its true then others should easily be able to replicate the results and prove or disprove it, if it cant stand up to that then it must not be true. So can anyone here back up the claims with controlled side by side experiments with more than one source? I would love to see them. Again, no offense to anyone meant.

Click to expand...

i hear you. i'm completely skeptical of any claims made about influencing sex. the main reason for this is NO ONE has ever presented to me a study of dna extracted from a cannabis plant (and believe me i've done plenty of searching on my own). therefore NO ONE can conclusively say at what point in the plant's development the gender becomes apparent. if you can't tell me that, then how on earth can you tell me how to "influence" this gender? no one has ever technically PROVEN that sex is determined in the seed. most of us accept this as truth, but the reality is that no one ever proved it. is the dna of a late-showing hermi the same as it was when the plant was a seedling? did something change in the plant or was it always there? the cannabis commumity basically speculates on this based on the life experience of stellar growers and breeders, but we have yet to prove jack shit on the subject as far as hard science is concerned.

Total Head said:

i hear you. i'm completely skeptical of any claims made about influencing sex. the main reason for this is NO ONE has ever presented to me a study of dna extracted from a cannabis plant (and believe me i've done plenty of searching on my own). therefore NO ONE can conclusively say at what point in the plant's development the gender becomes apparent. if you can't tell me that, then how on earth can you tell me how to "influence" this gender? no one has ever technically PROVEN that sex is determined in the seed. most of us accept this as truth, but the reality is that no one ever proved it. is the dna of a late-showing hermi the same as it was when the plant was a seedling? did something change in the plant or was it always there? the cannabis commumity basically speculates on this based on the life experience of stellar growers and breeders, but we have yet to prove jack shit on the subject as far as hard science is concerned.

Click to expand...

There is lots of proof that sex is predetermined in the seed. Besides, if sex wasn't predetermined there would be no way to make feminized seeds..

Kerovan said:

There is lots of proof that sex is predetermined in the seed. Besides, if sex wasn't predetermined there would be no way to make feminized seeds..

Click to expand...

ok but i'm really going to need you to point me at this proof because i've actively searched for it and came up with nothing. not calling you a liar, but i've really never seen any such evidence. and if anything the ability to influence sex tells me that it might NOT be predetermined, at least not in the way that i'm thinking. human gender is predetermined. you can't make a man into a woman without chemical and surgical intervention. cannabis works differently. i fully support the quest of the op, i just think he's flying blind because of the lack of scholarly published cannabis research, and interpreting his results might get dicey.

Total Head said:

ok but i'm really going to need you to point me at this proof because i've actively searched for it and came up with nothing.

Click to expand...

Sorry, but I cannot point you to the proof. It took a long long time of research and getting frustrated not finding stuff, and then more research. Didn't save any links. When I first heard of feminized seeds and thought about it, I didn't believe it could be done. So I started researching how it was done. Then started researching plant reproduction, so on and so forth. Most of the data didn't apply directly to mj, but to the class of plants it is in. These plants have both distinct male and female plants just like people. Reproduction happens when male pollen fertilizes the female flower and the seed is conceived. At that point the seed has the chromosomes that will either make it male or female depending on the combination. Nobody has to believe me since I don't have any links to proof. I am just stating what I found out.

Total Head said:

and if anything the ability to influence sex tells me that it might NOT be predetermined, at least not in the way that i'm thinking.

Click to expand...

This is proof. It is the way the sex is influenced. It is not by environment. There is a popular misconception that fem seeds come from hermaphrodites. They don't. Fem seeds come from a pure female plant that was forced in one way or another to produce a pollen pod similar to a male with pollen capable of reproduction. These are not 'true male' flowers though, it is 'pollen pod' with no male chromosomes, only female. This is why when that pollen inseminates a female flower the resulting seed is female. Only female chromosomes are present, so only a female can result.

Kerovan said:

Sorry, but I cannot point you to the proof. It took a long long time of research and getting frustrated not finding stuff, and then more research. Didn't save any links. When I first heard of feminized seeds and thought about it, I didn't believe it could be done. So I started researching how it was done. Then started researching plant reproduction, so on and so forth. Most of the data didn't apply directly to mj, but to the class of plants it is in. These plants have both distinct male and female plants just like people. Reproduction happens when male pollen fertilizes the female flower and the seed is conceived. At that point the seed has the chromosomes that will either make it male or female depending on the combination. Nobody has to believe me since I don't have any links to proof. I am just stating what I found out.



This is proof. It is the way the sex is influenced. It is not by environment. There is a popular misconception that fem seeds come from hermaphrodites. They don't. Fem seeds come from a pure female plant that was forced in one way or another to produce a pollen pod similar to a male with pollen capable of reproduction. These are not 'true male' flowers though, it is 'pollen pod' with no male chromosomes, only female. This is why when that pollen inseminates a female flower the resulting seed is female. Only female chromosomes are present, so only a female can result.

Click to expand...

i'm with you. the part that i get lost on is "forced one way or another to produce a pollen pod" (i do understand what it means and how it's done). that leads me to believe that the ability to produce that pollen pod was always there within the seed. that ability (just to me, maybe not in a scientific sense) prevents us from labling that plant a true female, regardless of what triggered the pollen sac or what chromosomes that pollen contains (and from what i can tell these triggers are still fairly mysterious and debatable). i understand it's different from a true hermi, but the fact remains that from a scientific standpoint we don't yet have the whole story as far as this paticular plant is concerned. i take issue with using research done on "similar" plants. the most similar plant i know of is hops and hops research has its limitations in the cannabis world. i have done much research about general plant sexuality but i hit a wall when determining how to accurately apply it to cannabis. i will admit if i had a stronger scientific background i may be able to make more sense of it, but all this "androecious" and "gynoecious" junk makes my head spin. i have to do 2 weeks of research just to interpret one article that may or may not pertain to what i need. that stuff is fine for a scientist, but i'm just a hobbiest. there's only so much searching i'm really qualified to do, and if someone can't make a concise "cannabis science for dummies" book for me i have to conclude it's because there's just not enough science info to do so. anything (and i mean anything) you want to know about cilantro can be found in 5 seconds on google. not so with cannabis. it's just pages upon pages of people talking about thier grows on forums like this and random medical studies and pure speculation. i want to see the microscope slide complete with lab and strain info, side by side scholarly studies, crap like that, presented a way that an intellegent layman can understand. hell it can even be all "sciencey" if it contains the info we need. i guess it sounds whiney, i'm just dissatisfied with the progress so far. it's 2010, ya know?

Sex determination occurring in the seed has been very well proven for a very long time. The MM Grow Bible is also pretty crappy IMO - it has a ton of bad and incorrect info in it. There are a ton of studies out there on the topic, here are a few:

http://www.nature.com/hdy/journal/v88/n2/abs/6800016a.html

https://www.thieme-connect.com/ejournals/abstract/plantbiology/doi/10.1055/s-2001-17735

Any intro biology book will confirm this as well. Sex is determined by the chromosomes (ie genetics) in all species. It is physically impossible for environment to directly influence genetics except in very extreme conditions. There is no scientific evidence that ANY living organism has it's DNA directly influenced by environment. Even the claim that you cited a lot that sex in reptiles is determined by temperatures has been thoroughly debunked. Claiming that something like humidity and temperatures will influence sex is basically saying that every single scientist the days of Mendell who has ever studied biology, and that every study done on genetics in the last century was completely, 100% wrong about genetics and how they work. If find it unlikely that that many scientists were that wrong for that long about one of the most fundamental principals of biology.

edit: I think what tends to confuse people a bit on this is the fact that cannabis is collectively an intersex (hermaphrodite) species. Because of this you can have a plant that is genetically a male but appears female or a plant that is genetically female that appears male since the sex expression is a bit plastic. When you are dealing with a hermi plant then environment can influence sexual expression, but it does not change the genetics - the sex of the plant remains the same.

Also there have been some studies done that have found that environmental conditions when the seed first form may influence sex ratios. This may explain why some seeds seem to have much higher rations of females to males, but this is still due to genetics, not the environment that the seedling is grown in.