The feminization thread

[c-ray]

Time to talk about the creation of feminized seed lines, the implications of using feminized seed lines in a breeding program, observations on growing feminized lines and their overall contribution to the greater cannabis gene pool.

If anyone has the Country Mon STS protocol and/or a giberrellic acid protocol please cut and paste at will.

[Glass Man]

I think Country Mon did one about using Colliodal Silver too. If someone has that one it would be good to post as well.

I'm looking forward to the development of this thread/topic , it's something which I plant to begin working on soon.

Thanks C-ray for beginning this thread.

[LordOvertoke]

i've got a text file labled STS....not sure but i think it's a copy from the Country Mon thread that Gob and luci contributed much too also....anyway, here's what i've got....thanks to all for sharing the info. :)

LO

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1. mix 2.6 grams of sodium thiosulphate into 600ml of distilled water and mix thoroughly.

2. mix .7 grams of silver nitrate into 100ml of distilled water and mix thoroughly.

3. mix silver nitrate solution into sodium thiosulphate solution while stirring rapidly.

4. top off mixture with distilled water to fill a glass quart jar (canning jar type).

5. use this mix at a 3:1 ratio with distilled water and spray plants to point of run-off.

6. repeat process in 3 days, move target females in at 5 days.

use common safety precautions. rubber gloves, safety glasses, skin covered, respirator preferred.

3:1 ratio of distilled water to stock mix of STS can be played with some. some people use it as diluted as 9:1 and some run it as hot as 1:1.

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[saskafarian]

"If anyone has the Country Mon STS protocol and/or a giberrellic acid protocol please cut and paste at will."

I just can't resist an invitation to cut n' paste

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Country Mon
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How To Reverse Sex Using Silver Thiosulfate Solution

The following is a safe, inexpensive, and successful method for reversing the sex of female cannabis plants. Individual plant responses may vary based upon strain, but I can verify that this process is fully effective in stimulating profuse staminate flower production.

This process can be used to:

A: create new feminized seeds from solitary prize mothers that you currently have
B: create interesting feminized-seed hybrids from different prize strains that you currently have
C: create feminized seeds for optimum outdoor use
D: accelerate the "interview" phase of cultivation, in searching for interesting new clone-mothers
E: reduce total plant numbers- great for medical users with severe plant number restrictions
F: increase variety, by helping to create stable feminized seedlines to be used as an alternative to clones

At the bottom of this post are some specific details about the chemicals used, their safety, their cost, and where to get them.

It is important to educate yourself about cannabis breeding theory and technique prior to using a method like this one. Here is a link to Robert Clarke's "Marijuana Botany", which is a very good reference.

"Marijuana Botany" by Robert Connell Clarke
(unfortunately missing the appendices)
http://www.geocities.com/hempgenes/Botany.html

It is also important to use basic safety precautions when mixing and handling these chemicals, so read the safety data links provided. The risk is similar to mixing and handling chemical fertilizers, and similar handling procedures are sufficient.

Remember: nothing will ever replace good genetics, and some of your bounty should always go back towards the professional cannabis breeders out there... the ones who have worked for many generations to come up with their true-breeding F1 masterpieces. Support professional breeders by buying their seeds. Also, order from Heaven's Stairway. Not that they need a plug from me, but they are very professional and provide very fast service worldwide.




Old Post October 7th, 2003 02:51 AM Edit/Delete Message Reply w/Quote Report this post to a moderator

[saskafarian]

Country Mon
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Preparation of STS:

First, a stock solution is made. It consists of two parts (A and B) that are initially mixed separately, then blended together. Part A is ALWAYS mixed into part B while stirring rapidly. Use distilled water; tap water may cause precipitates to form.

Wear gloves while mixing and using these chemicals, and mix and use in a properly ventilated area. A mask will prevent the breathing of any dust, which is caustic. STS is colorless and odorless, and poses minimal health risks if used as described here. (See material safety data sheet links below). Note that silver nitrate and STS can cause brown stains upon drying, so spray over newspaper and avoid spilling.

Part A: .5 gram silver nitrate stirred into 500ml distilled water
Part B: 2.5 grams sodium thiosulfate (anhydrous) stirred into 500ml distilled water

The silver nitrate dissolves within 15 seconds. The sodium thiosulfate takes 30-45 seconds to dissolve.

The silver nitrate solution (A) is then mixed into the sodium thiosulfate solution (B) while stirring rapidly. The resulting blend is stock silver thiosulfate solution (STS).

This stock solution is then diluted at a ratio of 1:9 to make a working solution. For example, 100ml of stock STS is added to 900ml of distilled water. This is then sprayed on select female plants.

Both the stock STS and the working solution should be refrigerated after use, as well as the powdered chemicals, to avoid activity loss. Excess working solution can be safely poured down the drain after use (with ample running water) with negligible environmental impact. It's pretty cheap.

Each liter of stock STS will make ten 1-liter batches of working solution of STS. With the minimum amount of base chemicals ordered from Photographer's Formulary (see link below), this means that each 1-liter bottle of working solution STS costs less than 9 cents, and can treat 15-20 mid-sized plants. That's 200 1-liter batches of STS for $18. Note that the distilled water costs far more than the chemicals.




Old Post October 7th, 2003 02:53 AM Edit/Delete Message Reply w/Quote Report this post to a moderator

[saskafarian]

Country Mon
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Application:

The STS working solution is sprayed on select female plants until runoff. Do the spraying over newspaper in a separate area from the flower room. You probably won't smell anything, but ventilate anyway. You now have what I call a "F>M plant"; a female plant that will produce male flowers.

After the F>M plant dries move it into 12/12 immediately. This is usually done three to four weeks prior to the date that the target (to be pollinated) plants will be ready to pollinate. Response times may vary slightly depending upon the strain. More specific times can be determined by trial with your own individual strains. In my trials it took 26 days for the first pollen. 30-35 days seems optimum for planning purposes.

So, assuming that a target plant needs 3-4 weeks to produce fully mature seeds, a strain that takes 8 weeks to mature should be moved into flower at about the same time as the female>male plant. A target plant that finishes flowering in 6 weeks needs to be moved into flower later (10 days or so) so that it doesn't finish before the seeds can fully mature.

A seeded individual branch can be left to mature on a plant for a bit longer, while harvesting the other seedless buds if they finish first. Just leave enough leaves on for the plant for it to stay healthy.

Effects:

Within days I noticed a yellowing of the leaves on the F>M plants. This effect persisted for two weeks or so; after this they became green again, except for a few of the larger fans. The plants otherwise seemed healthy. No burning was observed. Growth stopped dead for the first ten days, and then resumed slowly. No stretch was ever seen. After two weeks the F>M plants were obviously forming male flower clusters. Not just a few clusters of balls, but complete male flower tops. One plant still formed some pistillate flowers, but overall it was predominantly male.

It is strange indeed to see an old girlfriend that you know like the back of your hand go through a sex change. I'll admit that things were awkward between us at first.

When the F>M plants look like they may soon open and release pollen, ( 3-1/2 to 4 weeks) move them from the main flower room into another unventilated room or closet with lighting on a 12/12 timer. Don't worry too much about watts per square foot; it will only be temporary.

When the pollen flies, move your target plants into the closet and pollinate.

A more controlled approach is to isolate the F>M plants in a third remote closet (no light is necessary in this one, as they are releasing pollen now and are nearly finished anyway). In this remote other closet the pollen is very carefully collected in a plastic produce bag or newspaper sleeve and then brought back to the lighted closet, where the target plants are now located. If this is done, be careful to not mix pollen types by letting the F>Ms dust each other. Avoid movement, or use yet another closet.

Take special care to not let pollen gather on the outside of this bag- a static charge is sometimes present. Drop small open clusters of blooms inside and then close the bag at the mouth and shake. Important: next, step outside and slowly release the excess air from the bag, collapsing it completely, so that pollen doesn't get released accidently. Point downwind; don't let it get on your hands or clothes.

This collapsed pollinated bag is now very carefully slipped over only one branch and is then tied off tightly at the mouth around the branch stem with a twist tie or tape, sealing the pollen inside. Let the bag inflate slightly with air again before sealing it off, so the branch can breathe. This technique keeps the entire plant from seeding. Agitate the bag a bit after tying it off to distribute the pollen. Don't forget to label the branch so you know which seeds are which. Other branches on this same plant can be hit with different pollen sources.

If no lighted closet is available, the plant can be moved back into the main room, but- be very careful: pollen is sneaky. After 4-5 days, the bag is gently removed and the plant completes it's flowering cycle.

Yet another method has worked well for me. I position the target plants in a non-ventilated lighted closet, and then I collect pollen on a piece of mirror or glass. This is then carefully applied to the pistils of one pre-labeled branch by using a very fine watercolor paintbrush. Care is taken to not agitate the branch or the pollen. No sneezing. The plant needs to be in place first; moving it after pollination can shake pollen free and blow this technique.

Regardless of technique, at completion you will have feminized seeds. Let them dry for 2-4 weeks.




Old Post October 7th, 2003 02:56 AM Edit/Delete Message Reply w/Quote Report this post to a moderator

[saskafarian]

Country Mon
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About the chemicals:

Silver nitrate is a white crystalline light-sensitive chemical that is commonly used in photography. It is also used in babies' eyes at birth to prevent blindness. It can cause mild skin irritation, and it stains brown. Avoid breathing. I didn't notice any smell or fumes, but ventilation is recommended. Be sure to wash the spray bottle well before you use it elsewhere; better yet: devote a bottle to STS use. A half gram is a surprisingly small amount; it would fit inside a gel capsule.

Here are links to some safety data. A Google search will bring up more information if needed.

Silver Nitrate info:
http://www.cdc.gov/niosh/ipcsneng/neng1116.html
http://www.lions.odu.edu/~redwards/...%20solution.pdf

For a realistic hazard level comparison, here is a link for the safety and handling data for Ammonium Nitrate, or common fertilizer:
http://www.skcgulfcoast.com/nioshdb...ng/neng0216.htm

Sodium thiosulfate is also a white crystalline chemical commonly used in photography; it is used in photographic fixers. Same general cautions apply, minus the staining. This formula uses the anhydrous type. Non-hazardous.

Sodium Thiosulfate info:
http://ptcl.chem.ox.ac.uk/MSDS/SO/s...hiosulfate.html
http://www.med-chem.com/MSDS/Sodium_Thiosulf.htm

------------------

Where to get the chemicals:

http://www.photoformulary.com

silver nitrate: 10 grams: $10
http://www.photoformulary.com/Deskt...yID=27&langID=0

sodium thiosulfate (anhydrous): 100 grams: $3.95
http://www.photoformulary.com/Deskt...yID=28&langID=0

Postage runs around $4. Fast service. Can be shipped to Canada.




Old Post October 7th, 2003 02:58 AM Edit/Delete Message Reply w/Quote Report this post to a mo

[saskafarian]

The Country Mon
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Registered: Apr 2004
Location: Pacific Northwest
Posts: 223 Using STS For Sex Reversal: Conclusions
Hey, all...

I wanted to post some conclusions that I have come to regarding the successful reversal of plants using silver thiosulfate solution. It's been a year since I posted the other STS thread. I have done six batches myself, and have had full pollen release with all of them. Everyone else seems to be doing well, but there is very little feedback so who knows. A big thanks to those who contributed to the other thread... your input was a big help in refining the technique.

I was going to edit the original post, but I can't, as I am THE Country Mon now, not just Country Mon. Changed my email addy and got locked out.

There has been one key change that I want to pass along to everyone who didn't want to sift through the 25+ pages of the original thread.

I have discovered that using a stronger concentration of STS does not make a plant more likely to produce pollen. It just burns/stresses the plant. What DOES make a plant much more likely to complete it's mission and make pollen is a second spraying at the end of week 2.

My conclusion is that STS in any concentration is only effective at inhibiting ethylene for about 3 weeks; at that point the plant's natural female metabolism begins to take back control, and even a plant that is covered with male blooms can't finish the journey to manhood and produce pollen. A second spraying allows inhibition to last through week 6, which is more than enough time to release pollen.

Some of you have decided to use stronger concentrations of STS. This is fine as long as it doesn't burn your plants. Obviously there is a wide range of usable formulas that will work. But the second spraying is the key to follow-through. You can store the working solution you used for round one (in the spray bottle) in your refrigerator for two weeks; no need to mix a new batch from stock.

I don't see the point of going any stronger than the formula I originally came up with. It has proven itself many times over. The only change I might make is to adjust it slightly to Gobgoober's "molar-correct" mix ratio. This is not at all necessary, but does allow the most effective use of the chemicals together.

Here's a re-post of the formula mix instructions, with the adjusted recipe below that:

Preparation of STS:

First, a stock solution is made. It consists of two parts (A and B) that are initially mixed separately, then blended together. Part A is ALWAYS mixed into part B while stirring rapidly. Use distilled water; tap water may cause precipitates to form.

Wear gloves while mixing and using these chemicals, and mix and use in a properly ventilated area. A mask will prevent the breathing of any dust, which is caustic. STS is colorless and odorless, and poses minimal health risks if used as described here. (See material safety data sheet links below). Note that silver nitrate and STS can cause brown stains upon drying, so spray over newspaper and avoid spilling.

Part A: .5 gram silver nitrate stirred into 500ml distilled water
Part B: 2.5 grams sodium thiosulfate (anhydrous) stirred into 500ml distilled water

The silver nitrate dissolves within 15 seconds. The sodium thiosulfate takes 30-45 seconds to dissolve.

The silver nitrate solution (A) is then mixed into the sodium thiosulfate solution (B) while stirring rapidly. The resulting blend is stock silver thiosulfate solution (STS).

This stock solution is then diluted at a ratio of 1:9 to make a working solution. For example, 100ml of stock STS is added to 900ml of distilled water. This is then sprayed on select female plants.

Both the stock STS and the working solution should be refrigerated after use, as well as the powdered chemicals, to avoid activity loss.

The adjusted formula is as follows:

Part A: .7 gram silver nitrate stirred into 40ml distilled water
Part B: 2.6 grams sodium thiosulfate (anhydrous) stirred into 160 ml distilled water

Next, slowly add the silver nitrate solution to the sodium thiosulfate solution while stirring. This combination is then added to 800 ml of distilled water to equal 1 liter. This is your final stock solution. It is diluted 1:9 with more distilled water to make your final working solution, which then gets sprayed on your target plant.

Either formula will work great, so don't sweat it too much. But do that second spraying at the end of week 2... seems to be the key for getting pollen from the more difficult strains.

Please post your comments and experiences with STS.

CM


Last edited by The Country Mon on October 30th, 2004 at 11:08 PM

[saskafarian]

Posted by Telepod on May 6th, 2003 09:59 PM:


For what it's worth, here is some information I found about sex-reversal in cannabis. This was printed in the memoirs of H.Y. Mohan Ram, found as a .pdf file which I discovered by searching google for "Mohan Ram and Sett" as cited by Vic High on this board.
Here is a link to the .pdf file: http://www.ias.ac.in/jbiosci/dec2002/651.pdf -- I enjoyed reading this man's words, he seems like a wonderful and wise human being.

He states that fertile male flowers can be induced in female cannabis plants using:
gibberellins (GAs) and anti-ethylene agents such as:
silver nitrate (AgNO3)
silver thiosulphate anionic complex (STS)
aminoethoxyvinyl glycene (AVG)
and cobalt chloride (CoCl2).

As this was an aside mentioned in the larger context of Dr. Ram's life work, he does not go into detail regarding the methods of application of these chemicals to achieve the sex reversal. I'm sure the papers Vic mentioned will give the specifics, here they are again (thanks Vic):

Mohan Ram H Y and Juiswal VS. 1972. Induction of male flowers on female plants of Cannabis sativa by gibberellins and its inhibition by abscisic acid. Plants, 105:263-266.

Mohan Ram H Y and Sett R. 1981. Modification of growth and sex expression in Cannabis sativa by aminoethoxyvinylglycine and ethephon. Z. Pflanzenphysiol., 105:165-172.

Mohan Ram H Y and Sett R. 1982. Induction of fertile male flowers in genetically female Cannabis sativa plants by silver nitrate and silver thiosulphate anionic complex. Theor. Appl. Genet., 62:369-375
--------

[saskafarian]

C & P is my life!!!!!


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Polyploidy

Cannabis usually is a simple diploid plant, but polyploids having several sets of chromosomes can be produced by mutation. Polyploid cannabis usually is larger, produces more resin, and reproduces better than diploids. It is distinguishable by its darker, thicker foliage, and by microscopic analysis. Tetraploid monoecious hemp plants are selected by examination of the number and size of stomata, the number of epidermis and stoma cells, the size of pollen grains, and their number of pores. (19)

Polyploids are valuable for their genetic diversity, but they are unpredictable and usually are unstable in the first generation. They also tend to be sterile and must be propagated by clonal cuttings to be useful for subsequent breeding.

Studies by Warmke and Zhatov revealed that the normal sex ratio for diploids (2n) is nearly 1:1, but tetraploids (4n) form a new class (XXXY) and develop about 7.5 females:1 male, plus female-hermaphrodites. The XXXX is female; XXXY is female-hermaphroditic; XYYY is male-hermaphroditic, and YYYY is male. The XY determination of sex does not account, however, for the development of some monoecious strains. Seemingly, the sexual expression of hemp can be controlled by some other gene set(s) influencing different aspects of flowering. Environmental conditions also can overpower the genetic expression of Cannabis' gender, especially in the final stages of flower production. (20-23)

A. Zhatov (1979) reported these results of his research into hemp genetics:

"Change of ploidy... induced changes on some economically valuable characteristics and biological features. Tetraploid plants of dioecious hemp are characterized with sharply pronounced dioecism: plants with sexual deviations appear in the population of tetraploid hemp. Sex chromosomes of hemp on the tetraploid level play a paramount part in sex determination, but the process of determination is affected by autosomic genes...

"The viability of microspores of polyploid hemp is lower as compared with microspores of diploid hemp. During the storage, polyploid pollen loses the ability to produce pollen tubes of normal length. Selection of plants with the best regulated meiosis may raise the viability of polyploid microspores." (24, 25)

A. Zhatov, N. Migal, and other researchers have used gamma-irradiation of hempseed to mutate the subsequent plant. Presowing irradiation causes a drastic decrease in the survival rate of dioecious male plants and monoecious heterozygotic plants. Male sterility is manifested by empty pollen grains. The proportion of male plants in M1 is reduced to about 14%, and the height of plants is reduced by almost 75%. The number of branches and seed yields are increased, and the fiber content is increased by 30%. (26)

W. Hoffman and E. Knapp treated hemp seeds with x-rays, with these results:

"With increased dosage, the damage to the plants increased, the number of survivors decreased, and the sex ratio changed in favor of the females... With increased dosage, an increasing number of divergent types arose, especially of monoecious plants, and of male-like females. With increased dosage of x-rays, an increased percentage of tendrilled plants was also found... It is possible by means of x-ray treatment to change the sexuality of hemp and to get the normal dioecious hemp to a constant monoecious strain."

When hemp pollen is treated with ultraviolet light for one hour, the seed obtained from the resulting plants produces twice as many females as males.

Colchicine--- Tetraploidy can be induced by the mutagenic alkaloid colchicine, which is found in the autumn crocus, (colchicum autumnale). Colchicine allows a cell to double its chromosomes, but prevents meiosis (the splitting of cells), thus forcing the cells to become polyploid. When applied to cannabis, colchicine produces tetraploid plants which tend to be taller, with greater stem diameter, seed and pollen size. The THC content can increase up to 250%.(27)

A. Zhatov, et al., reported these findings from their research:

"The greatest % of polyploid plants is obtained when hemp plants are treated with 0.5% colchicine solution for 2 hours in the phase of cotyledon leaves. The treatment with colchicine solution inhibits growth. This inhibition continues for 2.5-3 weeks, after which the surviving plants resume normal growth and development. The guard cells in the leaves and the pollen grains of tetraploid plants are larger and the number of pores on the pollen grains are greater. Tetraploid plants are taller and the diameter of their stems, seed size and weight of 1000 seeds are greater. The anatomical structure of the stems differs from the diploid plants in a greater amount of primary and secondary fiber. The pollen viability of the tetraploid plants is lower than that of diploid plants. Vegetation period in tetraploids continues 8-15 days longer than in control plants." (28)

Colchicine also can sprayed on the seeds while they are developing on the mother plant. The flowers of plants treated in this manner should not be smoked because the concentration of colchicine may be dangerously high. A third method is to soak seeds in the solution for 2 to 4 hours. Colchicine stimulates the development of the taproot at first, but this effect ceases within a week; then the seedlings go into shock. About 30% of the survivors will be polyploid.

Colchicine can be bought, or prepared by grinding 100 grams of colchicum seeds to powder and percolating with 2 volumes of ethanol and 1 volume of water. The solution contains approximately 4 milligrams of colchicine. Label the bottle and store it safely: colchicine is toxic. Always wear rubber gloves when handling colchicine.

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I think this part is kinda interesting: "When hemp pollen is treated with ultraviolet light for one hour, the seed obtained from the resulting plants produces twice as many females as males"

[saskafarian]

Photoperiodism ---- Photoperiodic control can be very useful to the cannabis breeder. If yield is not important (as is often the case in the early stages of a breeding program), the time required for the life cycle can be greatly reduced by using short photoperiods. Thus, several generations of plants can be produced each year. Under such conditions, cannabis will flower when it is only a few inches tall. (62)

Photoperiodic control makes it possible to synchronize the flowering dates of male and female plants, thus making possible their cross-breeding. Most importantly, photoperiodic control enables breeders to stimulate the production of male flowers on female plants. Self-pollination can be accomplished only by means of such flowers. Male flowers on female hemp do not contain the Y (male) chromosome; they produce only female pollen. When this is used to fertilize female flowers on female plants, they will produce purely female seeds. The pollen from male flowers is of two kinds, and usually produces a ratio of males 1:1 females. A few viable seeds can be obtained from female flowers produced on male plants and self-pollinated, but such seeds are only weakly fertile and produce mostly female plants.

The following procedure will produce seeds which will grow 100% female hemp:

Cultivate two separate groups of female plants indoors. The plants should receive at least 50 watts of light per square foot of growing area. One group must not receive more than 7 hours of light daily. This will induce male flowers to manifest on the female plants. The second group of females must receive about 16 hours of light daily to ensure that no male flowers develop on them. The long photoperiod also inhibits the development of flowers so much that the short-day plants will mature 2 or 3 weeks before the long-day group. Therefore, begin cultivating the long-day females at least 2 weeks before planting the short-day plants.

As the two groups approach maturity, remove any males which may appear. A few weeks before the male hemp begins to flower, the internodes of the stem begin to elongate very quickly. The dominant male enzyme andrase produces thin plants with a tuft of leaves at the top. The leaves are smaller than those of the females, and have fewer leaflets (usually 5). Tiny buds sometimes appear in the nodes about 2/3 up the stalk. The future sexual expression of hemp may be determined by examining these premature flowers. If the buds remain erect, the plant is female. If the buds droop, the plant is male.

When clusters of female buds begin to appear on plants in the long-day group, cover each bud with a transparent plastic bag sealed with a rubber band around the stem below the bud cluster, so as to protect the flowers from accidental pollination.

When male buds appear on some of the female plants in the short-day group, cover each bud with a transparent bag sealed with a rubber band around the stem below the bud cluster, so as to protect the female flowers from accidental pollination.

When male buds appear on some of the females in the short-day group, carefully cut off every male bud and store them in a glass jar. Any new male buds which appear also must be pruned. Within a few days the anthers of the clipped buds will open and release pollen. Collect this pollen and apply it with a thin brush to the stigmas of the bagged flowers in the long-day group. Because this pollen contains only female chromosomes, the fertilized female flowers on the long-day female group will develop seeds which will produce only female plants.(63-66)

Another method of manipulating the gender of cannabis involves treatment of the male pollen with ultra-violet light for about 1 hour. This doubles the ratio of the females to males, perhaps by neutering the weaker male chromosomes. (67, 68)

The viability of hemp pollen can be preserved by the method of Migal and Arinshtein:

Storage of pollen in a refrigerator will protect breeding material for 38-45 days, which is important for crossing different varieties of hemp. Hemp pollen can also be stored in the dark placing it in a desiccator over calcium chloride or concentrated sulfuric acid. Here the pollen grains retain the viability to germinate for 12-18 days. The pollen of dioecious varieties of hemp retain viability longer than the pollen of monoecious varieties. (69)

[saskafarian]

.9 ~ Sexual Expression

The sexual expression of cannabis is determined by its genetic makeup, and by its metabolic temper, which is regulated by the male enzyme andrase and the female enzyme gynase. Environmental conditions (light, nutrients, soil and water) may suppress the formation of the dominant enzyme, and allow the opposite sex to express itself partially (hermaphroditism) or completely (sex reversal). (71, 72)

E. Galoch found that cytokinin is important for the sexual expession of hemp:

"Transition of female and male hemp plants from the vegetative to the generative phase is associated with a rise in cytokinin level while that of male inflorescences proceeds at a decreasing cytokinin level. The activity of cytokinins apparently is associated with an enhancement of the female tendency..." (73)

Gibberellin will inhibit the formation of flowers on cannabis, but sometimes it will otherwise cause the growth of fertile female flowers on genetically male plants. Silver nitrate or cobalt chloride causes masculinization of flowers of female hemp, possibly due to blockage of ethylene synthesis. High levels of N salts --- and long photoperiods --- have a masculinizing effect on hemp.(74-76)

According to K. Conrad, there are sex-linked differences of the auxin content in male and female hemp plants:

"During blossoming the vegetative parts of the males contain more auxin than those of the females. In the dying leaves and stems a remarkable increase of auxin can be observed." (77)

J. Heslop-Harrison studied auxin and sexuality in Cannabis:

"Dioecious hemp plants were grown to an age of 20 days in a day-length of 21-22 hours, then given an inductive treatment of ten 8-hour days to initiate flowering. After return to long days and during the period of differentiation of flower buds, a total of 0.5 gr lanolin paste containing 0.5% NapthaleneAcetic Acid (NAA) was applied to leaves at the 3rd and 4th nodes. In genetically male plants, female plants were subsequently formed in sites which would normally be occupied by males, a result which appears to be regulated by the level of native auxin in the vicinity of meristems during the period of differentiation of flower primordia. Secondary effect of auxin treatment were evident in an over-all reduction in intensity of heteroblastic development, the trend towards a reduction of leaf lobing and serration which normally accompanies plants passing through a period of flowering than in untreated controls." (78)

Nitrogen fertilizers masculinize the phenotype by stimulating the formation of male flowers. The proportion, number and degree of monoecious plants increases with increasing N, and the total N content is always higher in monoecious individuals than it is in females. (79)

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.

Hempseed can be feminized while they are forming on the plant. Fruit peels are spread around the area for two weeks before the plants enter the flowering phase. Remove the skins when the plants begin to flower. Otherwise, treatment with Etephon will accomplish the same effect.

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. (80)

A.I. Zhatov tested the effects of ethrel on hemp:

"Treatment of hemp plants with an aqueous solution of ethrel changed the ratio of male to female flowers. The greatest effect was observed when plants were treated during flowering of male flowers." (81)

Electricity also can change the sexual expression of cannabis; B.R. Lazarenko and I.B. Gorbatovskaya reported:

"Under the influence of the electrical current, the numerical proportions between hemp plants of different sexes was changed by comparison with the control to give an increase of female plants by 20-25%... The characteristics acquired by the plants in electrically treated soils are transmitted by inheritance to the third generation..." [emphasis added] (82)

Photoperiodism is a most useful tool with which to control the sexual expression of cannabis. For example, J. Limberk made a careful study of lighttime on the sexual index of hemp, and reported thus:

"Male plants usually flowered earlier than female. Female plants flowered only when the period of daylight was shorter than 14 hours; male plants flowered even when the day was longer than 14 hours. Reduction of light intensity in the first stages of plant development lead to increases of female plants by 4.3%. Intersexual plants (22-30% of the total) were present in conditions of 11-13 hours light per day. Grafting of plants did not change sex."

Monoeciousness effected by short days is not fixed in the descendants. (84)

The probable future sex of a pre-floral hemp plant can be guessed at by calculating the Leaf-Mass Index (LMI): Count the points (3, 5, 7) on 3 leaves in the center of a cluster. Divide that number by 3 to determine the average number of points. Repeat the process several times, and figure that average also. Multiply the two averages to determine the LMI. A high LMI indicates that the plant will be female.

The phyllotaxy changes to alternate just before the onset of flowering. Then the sex of the plant can be determined by making a close examination of the upper nodes of the main stem. The onset of flowering is indicated by the appearance of undifferentiated primordial buds behind the stipules at the nodes of the petioles (along the stem at the base of branches). Within a few days they differentiate. The male pistils are flat or knobby with a curved shape and 5 open petals about 5 mm. long; they have a single tiny stalk. Overlapping vegetation often disguises their appearance.

The female develops pairs of flowers surrounded by pointed bracts of protective leaves that will enclose the seed. The female stigma usually appear as 2 fuzzy white hairs forming a "V" that protrudes from a bract. Resinous hairs (glandular trichromes) cover the calyx (2-6 mm long).

[saskafarian]

Gibberellin --- When seeds absorb water, the hormone gibberellin (gibberellic acid-A, GAA) appears in the embryo and activates the metabolism to initiate sprouting. GAA has been widely tested in applications to hemp.

When applied to cannabis at a rate of 100 ppm in water for 2 months, GAA increases the thickness and internodal length of the stock. The terminal nodes are weak, branching is suppressed, and the roots develop poorly. Germination is stimulated by GAA, but leaf growth and the production of chlorophyll and cannabinoids are reduced proportionately. GAA treatment does not hasten the generative development of hemp, but does promote plant growth. The stem diameter increases about 250% over control plants, and the fresh weight of the stem increases 300%. Treated plants have a higher ratio of bark:wood. The number of fibers increases up to 100%.

According to G. Davidyan, the greatest effect is achieved with 0.005-0.01% GAA applied before the buds form.

R. Herich tested the histological reactions of hemp by soaking the seeds in 5 ppm GAA for 24 hours with these results:

"The plants showed the following differences from untreated controls: decrease of stem thickness, less lignification, decreased bark development especially in lower parts of stems, decrease in number of secondary bast fibers, increase in number and size of primary bast fibers, and increased differentiation of parenchymatous pith tissue". (63)

C.K. Atal also described the effect of GAA on hemp:

"Gibberellin-treated plants showed a greater number of fibers as compared to controls. The individual fibers were larger in diameter, more lignified, and up to 10 times as long as the fibers from the untreated plants." (64)

F. Yanishevskii studied the effect of GAA on the nitrogen metabolism of hemp:

"Stem lengthening took place mainly by cell extension. Net weight even decreased somewhat. Chlorophyll concentration decreased noticeably... Plants treated with GAA contained less N than controls. GAA exerted a considerable influence on the N metabolism of hemp plants: in treated plants the amount of protein N decreased 2-fold, but, in contrast, the soluble forms of N increased markedly. Treatment with GAA had almost no effect on the content of N fractions of cell components (nuclei, plastids). Nucleic acid content decreased mainly owing to decrease in the amount of RNA. Accumulation of soluble forms of N under the influence of GAA would indicate that the introduction of nitrogenous fertilizers (as recommended by Witter and Bucovac) would hardly make up for the unfavorable effect of GAA on the N metabolism of hemp." (65)

N. Yakushkina and L. Chuikova also tested the action of GAA and Indole-Acetic Acid (IAA, auxin) on hemp:

"GAA intensified the growth of the plants, the average dry weight per plant, the photosynthesis rate, the sugar content (especially of the stem) and that of total N, and the respiration rate, but decreased the content of chlorophyll in the leaves. The separate application of IAA caused a decrease in the growth and yield of the plants, and a considerable increase in the chlorophyll content, but decreased the photosynthesis rate. The simultaneous application of GAA and IAA was accompanied by the highest increase in yield, but this addition of IAA did not exert any substantial influence on the physiological processes." (66 )

GAA also increases the length of the growing season. GAA will inhibit the formation of flowers on Cannabis; it must not be used during the flowering phase of growth. GAA will accelerate the onset of budding by about 7 days.

Treatment of plants with 25 mg GAA/liter results in 80% of the plants being male. Female hemp usually undergoes sex reversal to a male expression, but few of the male plants produce female flowers. Thus, G. Davidyan and S. Kutuzova reported:

"Gibberellin causes the formation of male flowers, containing fertile pollen, on genetically female plants." (67)

V. Khryanin treated dioecious hemp with GAA (25 mg/liter) and produced monoecious feminized staminate hemp from the common pistillate form:

"Gibberellin, as a hormone of the plant organism, probably depresses genes which participate in the formation of flowers which have been repressed.

"Thus GAA can be used by breeders to develop monoecious cannabis from dioecious forms. Preliminary tests are necessary to determine the most effective concentration and best timing for each cultivar."

Gibberellin is extracted from cucumber seeds, fresh cantelope seeds, dried corn kernels, and from pencil rod, lupine, and pinto beans. Soak 200 grams of powdered seeds in 110 ml of a mixture of acetone (10 parts), isopropyl alcohol (5 p), ethanol (2 p), and water (5 p). Filter the mush and rinse it with 20 ml acetone and 20 ml isopropyl alcohol. Combine the rinse and the mother liquor, then evaporate the solvent. Dissolve the gum in alkaline water for experimental use.

The effect of GAA is removed by abscisic acid (ABA), which will initiate flowering. Treatment of plants with ABA (10 mg/liter) results in all plants being female or bisexual. The ABA can be overcome by increasing the concentration of GAA. (68)

[saskafarian]

Farmers in India sometimes soak the seeds overnight in milk and water before sowing. A traditional Chinese method of stimulating the germination of hempseed is to soak them in an aqueous extract of the plant. According to V.E. Sustrina, this also increases the number of females:

"Hemp seeds were soaked at 10-15o C in extracts of dry inflorescences; the percentage of staminate plants was greatly reduced." (19)

[saskafarian]

And for all male seeds:

The transition of male to female flowers can be accomplished by wounding the infloresences of male plants. The anther lobes will transform into ovules. The earlier this process begins, the more normal is the development of female flowers. Bisexual flowers also are obtained. (50)

[saskafarian]

And one from Soma:

RODELIZATION: SOMA'S WAY TO FEMALE SEEDS
Here’s an easy, environmentally friendly method for breeding feminized seeds.
2003-07-30 >> grow category >> grow articles

Story by Soma


Creating feminized cannabis seeds is an art. Just like art, there are a few different methods of application. I have written about some of my different methods of making seeds in previous HIGH TIMES articles. I have used gibberellic acid, pH stress, light stress, and fertilizer stress to force my female plants to make seeds. All of these methods are harsh on the plants, and some, like the gibberellic acid, are not organic. In my search for cleaner, more earth-friendly ways of working with the cannabis plant, I have found a new way to make feminized seeds.

Feminized seeds occur as a result of stress, rather than genetics. All cannabis plants can and will make male flowers under stress. Certain strains like a higher pH, some a lower one. Some like a lot of food, some like much less. There is quite a lot of variety in marijuana genetics, and you can’t treat every plant the same way.

It takes many harvests before you really get to know a particular strain. Just like getting to know human friends, it takes time. I have grown the same strains for close to a decade, and am truly getting to know every nuance the different plants exhibit. I can recognize them from a distance. I must say that I get a lot of help from my friends, both in making seeds and in learning new and better ways of working with this sacred plant.

I named this new method "Rodelization," after a friend who helped me realize and make use of this way of creating female seeds. After growing crop after crop of the same plants in the same conditions, I noticed that if I flowered the plants 10-14 days longer than usual, they would develop male "bananas." A male banana is a very slight male flower on a female marijuana plant that is formed because of stress. Usually they do not let out any pollen early enough to make seeds, but they sometimes do. They are a built-in safety factor so that in case of severe conditions, the plant can make sure the species is furthered.

To me, a male banana is quite a beautiful thing. It has the potential of making all female seeds. Many growers out there have male-banana phobia. They see one and have heart palpitations, they want to cut down the entire crop, or at the very least take tweezers and pluck the little yellow emergency devices out. I call them "emergency devices" because they emerge at times of stress.

In the Rodelization method, the male banana is very valuable. After growing your female plants 10-14 days longer than usual, hang them up to dry, then carefully take them off the drying lines and inspect for bananas. Each and every banana should be removed, and placed in a small bag labeled very accurately. These sealed bags can be placed in the fridge for one or two months and still remain potent.

For the next phase, you need to have a separate crop that’s already 2 1/2 weeks into flowering. Take your sealed bags of pollen out of the fridge, and proceed to impregnate your new crop of females. To do this, you must first match the female plant and the pollen from the same strain in the previous crop. Shut all the fans in the growroom down. Then take a very fine paintbrush, dip it in the bag of pollen, and paint it on the female flower. Do this to each different strain you have growing together. I have done it with up to 10 different kinds in the same room with great success.

I use the lower flowers to make seeds, leaving the top colas seedless for smoking. This method takes time (two crops), but is completely organic, and lets you have great-quality smoke at the same time you make your female seeds. If you’re one of those growers who’s never grown seeds for fear of not having something good to smoke, you will love this method.

You can also use this pollen to make new female crosses by cross-pollinating. The older females with the male bananas can be brought into the room with the younger, unpollinated females after they are three weeks into flowering. Turn all of the circulation fans on high, and the little bits of pollen will proceed to make it around the room. Do this for several days. Six to seven weeks later, you will have ripe 100% feminized seeds; not nearly as many as a male plant would make, but enough to start over somewhere else with the same genetics.

As a farmer who has been forced to move his genetics far away from where they started, I know very well the value of seeds. My friend Adam from ThSeeds in Amsterdam has a motto that I love to borrow these days: Drop seeds not bombs.

[c-ray]

I think everyone now knows about 'rodelization' and why it is not a viable method of feminization

[Hashmasta-Kut]

and also, thanks for the cut and paste.

[Dman]

Hi Folks,

Remeber to apply the second application of STS 2 weeks after flowering is induced. This is the most effective way to reverse tough strains. I've played with the dilution ratios, and stronger strengths seem to have no effect in reversing stubborn strains.
The second app is crucial to get TONS of pollen from just about ANY strain....even at the 9:1 ratio! ;)

[kephra]

How about a C & P of Cabron's Colloidal Silver thread. :)

[Chuk]

Hi,
What your opinion on it http://www.getcl-one.com/1.html

Chuk

[mojojojo]

ive tried to reverse the sour d cut and it didnt pollenate anything even though it reversed.
just sprayed bubba last week but i know that one can be reversed.
wonder why some plants it dosent work with.
peace

[maccapacca]

Can anyone point me in the right direction for both the chemicals required to make STS? im in the UK and Im having trouble finding these products.

thanks,

MAC

[c-ray]

specialty photography supply shops or ebay
for instance -> http://www.silverprint.co.uk/chem24.html

here's a list of other places around the world that might stock silver nitrate and sodium thiosulphate -> http://www.alternativephotography.com/shop/dir_chemicals.html

good luck, stay safe (goggles, labcoat, gloves, long sleeve shirts, etc.)

[maccapacca]

excellent c-ray, I spent over an hour trying to find a UK supplier last night online with no success! thanks for your help

Mac

[cabron]

Using a gal that has all the traits that make your heart pitter patter is the fastest way to get to the finish line correctly...

What is the finish line? it's the ability to hand a batch of beans to a competent grower knowing that every one is going to be a gem that
has all the facets of a diamond in respect to flavor,high,stature,smell
growth and taste...

Everybody has a particular idea or image of what a perfect plant should be
and that is the goal that they should strive for to make available to others
that pheno or a small group of them,So they too can appreciate your Joy you had in maintaining a plant that the love is reciprocating.

I am currently in the progress of making a stable offering of the sought after
Pineapple pheno of C99, but I also want it to be a heavy yielder,I've had this
and it was a doll..
I know for sure that it's going to take a long time and big numbers going with male pollen and using the traditional methods,,I'm going to first boost my seedstock numbers with the same genepool and then start my selection with many gals.

If I was to use males I can't tell by looking at them which is going to have the alleles in proper order that create that pineapple pheno,,,this trait is only distinguishable after she flowers.
If I was to systemattically document all males and make seeds grwo them out and go from there to work through the generations to properly inbreed and bottleneck this trait and pheno it would take years to do properly so I could honestly say that these beans will be 90% pineapple pheno and heavy yielders.

Or I could inbreed exclusively with Gals of this pheno while excluding F2,F3,F4
etc.. offspring that are not fitting the bill.

Soon within 3-4 generations you would have easily created a line that is all happiness and joy!!!

I plan on keeping the combination of genes intact that Joey had started out with being NL and C99 as the NL really beefed up the yields but the C99 in this case came through as the dominant pheno.
Traits I'm focused on are the great up high that inspires me to write and sing better,the band members think rehersals are
best smoking this pheno,,,creativity at it's best...huge chunky,low leaf floral clusters,that are caked with trichs that smell so
sickly sweet,huge central cola with all the branches carrying a comparably sweet bud...These have to produce a main cola
with minimal branching when flowered @ 8-12" from cuttings...and hold this structure whie grown in soil or hydro.
Be done by 60 days max.....so theres my challenge....

The Bros Grimm had originally done this by bringing the Shiva Skunk in the initial cross to the momma to create boys to choose from with the Princess
and cafe girl genes present.

Vigor has been reintroduced into this line with the introduction of the NL,it hasn't influenced the C99 too much at all in any way negatively.

I can't have high numbers due to my love of freedom and poontang,,,so I prefer to keep 90% of my plants female.

But I can select properly from let's say 25 gals and be more accurate with regards to combining results, equal to 100's of boys.