How to alter the % of females

[HippyInEngland]

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

 

[snuggles]

- 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).


The above I have read before and even tried to follow those "rules" a couple of times, I have a difficult time getting males so I believe the temp and humidity part...honestly this past year I have had 4 males in total maybe five...LOL. And I tend to grow quite a bit. But who the hell knows for certain. It's one of those things that I have heard a million times and never had verified by anyone who knows for sure. The birth control seems a bit much considering, and so does the CO.

 

[Puffin Afatty]

another anecdotal suggestion I've seen is to keep air flow off the seedlings until sexing, as more males grew on the windward as opposed to the leeward side of the grow.

 

[Kupunakane]

Yo Ho Hippy,

I have read this with rapt attention, and I think it is seriously misleading at best. I am a breeder of exotic plants, and I assure you that the DNA program that determines the sex of a plant is in place shortly after fertilization. If you are trying to alter an existing male or female then this might help.

Galoch (1978) indicated that gibberellic acid (GA3) promoted stamen production while indoleacetic acid (IAA), ethrel, and kinetin promoted pistil production in prefloral dioecious Marijuana. Sex alteration has several useful applications. Most importantly, if only one parent expressing a desirable trait can be found, it is difficult to perform a cross unless it happens to be a hermaphrodite plant. Hormones might be used to change the sex of a cutting from the desirable plant, and this cutting used to mate with it. This is most easily accomplished by changing a pistillate cutting to a staminate (pollen) parent, using a spray of 100 ppm gibberellic acid in water each day for five consecutive days. Within two weeks staminate flowers may appear. Pollen can then be collected for selfing with the original pistillate parent. Offspring from the cross should also be mostly pistillate since the breeder is selfing for pistillate sexuality. Staminate parents reversed to pistillate floral production make inferior seed-parents since few pistillate flowers and seeds are formed.


If entire crops could be manipulated early in life to produce all pistillate or staminate plants, seed production and seedless drug Marijuana production would be greatly facilitated.


Sex reversal for breeding can also be accomplished by mutilation and by photoperiod alteration. A well-rooted, flourishing cutting from the parent plant is pruned back to 25% of its original size and stripped of all its remaining flowers. New growth will appear within a few days, and several flowers of reversed sexual type often appear. Flowers of the unwanted sex are removed until the cutting is needed for fertilization. Extremely short light cycles (6-8 hour photoperiod) can also cause sex reversal. How ever, this process takes longer and is much more difficult to perform in the field.


smoke in peace
KingKahuuna

 

[HippyInEngland]

Yo KK

Salutations

Ive read where you got your info from and yes its interesting, i find this quite fascinating, dna structure is changeable and who knows what one of us may stumble on 1 day.

 

[Kupunakane]

Hey there Hippy,
Yeppers, I couldn't agree more. It is rough trying to figuere out who knows what they are talking about, who is a wanna be scholar as far as MJ is concerned,
Some day one of us WILL stumble upon something great growing, and it will change everything.
By the way, thank you for the salutations. You received what I had to say in a very gentlemanly fashion, even if I am wrong it's fun to have someone that you can toss it all back and forth with. The persuit of learning is where it all boils down to. I can handle someone saying, "naw-naw, wait dude your wrong", or even "off in left field somewhere", BUT what I admire the most is when two or more heads, (fruedian slip,LOL), can get together even though they disagree, and they put their collective brains together in search of the right answer.
Oh , yes you are right about the DNA being able to be altered, BUT not after it has combined with another set of DNA from a pollination. You have to wait untill you can breed again to do that. Forcing a plant into a sex change (hermie) does NOT alter its DNA. I cannot begin to describe how badly I would love to do this genetic remodeling work.

Thanks for your being cool dude
smoke in peace
KingKahuuna

 

[mal_crane]

First, I'd just like to say that most of this information came from a falsely reported post taken from Dutch Passions to Overgrow, which was when I first started doing research on these issues. The report was originally done on feminised seeds.

Second, I'd also like to say that, I am partially responsible for a recent revival in those DP beliefs simply because I can cut and paste the information without having to write such a long answer like this because until finding this thread and a thread on another forum I belong to, I thought that everyone was in general agreement about this issue. Apparently I was severely mistaken.

Third, I want you all to know I'm not trying to start an argument, nor am I declaring what I say is fact because it isn't, only opinions based on my own personal grows and research. Over the course of the last 10 or 15 grows that I experimented these 'myths' on, I have discovered on my own semi-controlled grows that certain environmental factors do have an affect on the gender of the plant. I say semi-controlled because I have never had ph problems with my plants, therefore I use no ph meter. I am not disclosing scientific research, so please don't send an attack my way as if I am. Unless I am just a lucky guy and manage to get only 5-10% predetermined male seeds, then these are environmental factors I have noticed that seemed to have some sort of affect on the gender of my plants and only have an affect up until about 1 month of growth:

• 24/0 lighting seems to give me more males, which is why I no longer use it.

• 18/6 lighting seems to give me more females.

• Using 12/12 from sprout doesn't seem to give any higher of a concentration of females than 18/6.

• Constant temps between 65-75f seems to produce more females, while any constant above 80 gives me a higher concentration of males.

• A humidity above 40% seems to produce more females, while a humidity below 25% somehow has shown more males to develop.

I regret to inform all of you that I can't produce any information about different nutrient levels affecting the sex of the plant. And please remember, I am not submitting any of this as fact, only factors that have changed my grows. I'd also like to say that a Jorge Cervantes book was where DP got there information. Can anybody guess which one? I'll give +rep for that answer! :smoke1:

 

[Mutt]

http://www.natureinstitute.org/txt/ch/details/GENETICS.pdf

 

[mal_crane]

Interesting, I only got to flip through the pages, but I definately want to take the time to read this later on.

 

[Mutt]

Oh , yes you are right about the DNA being able to be altered, BUT not after it has combined with another set of DNA from a pollination. You have to wait untill you can breed again to do that. Forcing a plant into a sex change (hermie) does NOT alter its DNA. I cannot begin to describe how badly I would love to do this genetic remodeling work.

Something isn't adding up for me in this post.
Reversing the plant then self pollentaing is changing the genetic traits for that offspring. Otherwise feminization would not occur.
Environmental factors such as lighting and medium will have an effect on offspring.

 

[snuggles]

First, I'd just like to say that most of this information came from a falsely reported post taken from Dutch Passions to Overgrow, which was when I first started doing research on these issues. The report was originally done on feminised seeds.

Second, I'd also like to say that, I am partially responsible for a recent revival in those DP beliefs simply because I can cut and paste the information without having to write such a long answer like this because until finding this thread and a thread on another forum I belong to, I thought that everyone was in general agreement about this issue. Apparently I was severely mistaken.

Third, I want you all to know I'm not trying to start an argument, nor am I declaring what I say is fact because it isn't, only opinions based on my own personal grows and research. Over the course of the last 10 or 15 grows that I experimented these 'myths' on, I have discovered on my own semi-controlled grows that certain environmental factors do have an affect on the gender of the plant. I say semi-controlled because I have never had ph problems with my plants, therefore I use no ph meter. I am not disclosing scientific research, so please don't send an attack my way as if I am. Unless I am just a lucky guy and manage to get only 5-10% predetermined male seeds, then these are environmental factors I have noticed that seemed to have some sort of affect on the gender of my plants and only have an affect up until about 1 month of growth:

• 24/0 lighting seems to give me more males, which is why I no longer use it.

• 18/6 lighting seems to give me more females.

• Using 12/12 from sprout doesn't seem to give any higher of a concentration of females than 18/6.

• Constant temps between 65-75f seems to produce more females, while any constant above 80 gives me a higher concentration of males.

• A humidity above 40% seems to produce more females, while a humidity below 25% somehow has shown more males to develop.

I regret to inform all of you that I can't produce any information about different nutrient levels affecting the sex of the plant. And please remember, I am not submitting any of this as fact, only factors that have changed my grows. I'd also like to say that a Jorge Cervantes book was where DP got there information. Can anybody guess which one? I'll give +rep for that answer! :smoke1:

I only have one of his books, the "how to grow MJ". I also have it in a book that he didn't write......

This is an interesting thread though, I would like to see if anyone could verify this one way or another...like I said I see this pop up on numerous forums at least weekly, but no one has ever said "it works". Some of the factors might very well be true but some aren't for sure. Like CO, a plant needs O2 and CO2, I would think carbon monoxide would also be harmful to a plant, as it is to any organism that needs O2 to survive. And the birth control pills are hormonal (I might be wrong just a guess) somehow how I don't think this would work either.

 

[Mutt]

I only have one of his books, the "how to grow MJ". I also have it in a book that he didn't write......

This is an interesting thread though, I would like to see if anyone could verify this one way or another...like I said I see this pop up on numerous forums at least weekly, but no one has ever said "it works". Some of the factors might very well be true but some aren't for sure. Like CO, a plant needs O2 and CO2, I would think carbon monoxide would also be harmful to a plant, as it is to any organism that needs O2 to survive. And the birth control pills are hormonal (I might be wrong just a guess) somehow how I don't think this would work either.

I will contest that my ratios have gone up as well by following the method. The entire article is posted up in the advanced section as a sticky. Spectrum seemed to be the most beneficial aspect of what was printed. I watched my ratios drop when vegging under HPS but get up to 90% using mixed flos. Just what I "experienced" for myself.

 

[snuggles]

OK twice I tried the lower temps. and higher humidity, N strong foods, and blue light. First time was 8/9 female the second time I was 8/8 female. These numbers are too small for me to come to a conclusion, and I'm no plant scientist so who knows.

 

[Kupunakane]

Hey there Mutt,
Like I was saying to Hippy, I think the idea here is to learn one way or the other, with no attacks. To me that is cool. You should also know that I am a breeder of exotic plants, not MJ, (yet). I can certainly be wrong, and if so will humbly admit my error. Heck I'm not too proud to admit my goofs.
Based on what I was reading from the posts in here, it sounded as if some folks were under the impression that you can take a seed, germ it, then once you have growth established you can subject the plant to different things, and increase the odds that you will have a female develope. All I stated was that when the seed is still in your hand, the sex at that point has already been determined.
I agree that you can dink with the plant after growth has been established, and bring about a change, ie. a hermie, or you can chemically cause a change.
I am still studying this in great depth, because obviously if something could alter that seeds sex then I would like to know as would all the rest of us to be sure.
Carefull breeding has developed the feminized seed, but that is different, that's breeding, not what is being said here. this is just my $0.02

smoke in peace
KingKahuuna

 

[Mutt]

Oh not at all attacking KK. Just saying I didn't see that one. Still a very interesting subject. All of it is debatable when it comes to breeding, traits environment, I love discussing it. There is so many ways to look at this herb.

(but I got my outlook on femd seeds...Never will agree with it)

 

[papabeach1]

uhhh.. I do like these methods.. what do you think of pez's boot camp light methods 12/12 for 10 days, 24 then 12/12 for 5 days then 24, then 12/12 for couple of week? along with high N, and estrogen, also go for that b.c. to dilute with water for the watering... all that to promote more females?

 

[st00ner]

If I am growing Feminized seeds, should I worry about running my lights 24/7?

My seeds are about a week into life, is it to late to change the lighting cycle?

 

[papabeach1]

If I am growing Feminized seeds, should I worry about running my lights 24/7?

My seeds are about a week into life, is it to late to change the lighting cycle?

IMO...seed banks whoever says you can get little chance to have males...
that where I'm little concern about that.. if they say I'm gonna have 50/50 chance with female, I ll just hang up...

the more we learn to get more ratio of females, and we all will be fine..

 

[THCPezDispenser]

I will contest that my ratios have gone up as well by following the method. The entire article is posted up in the advanced section as a sticky. Spectrum seemed to be the most beneficial aspect of what was printed. I watched my ratios drop when vegging under HPS but get up to 90% using mixed flos. Just what I "experienced" for myself.

I think if someone is willing to use a pack of feminized seeds and do a converse experiment, the results can add a lot of value to this question. The feminized seeds are "XX" due to how they are made. They are not super females, just guarateed to have been passed the "XX" chromosomes. The test seeds must be from a reputable feminizer who uses GA3 and not hermies. If, by using all the "wrong" environmental factors you can get a significant amount of males out of this pack of seeds, this should prove the point that environment can change sex. Anyone have the space and the wherewithal to take this on ?

 

[papabeach1]

hey mutt? did you do these with bagseeds?


we would like to know please... sound like pez saying you did it with femmine seeds..