How To Reverse Sex Using Silver Thiosulfate Solution

[Blazinjones]

I forget where I got that but I put it in my notes awhile back.

Hey bro i was wondering if u know how to store pollen an if so how long does it stay gud for. Here is 2 tops of my pineapple express auto tht i used sts on im letting the rest stay on the plant to develop more.

This is just the pollen tht fell off while snipping leaves off to get at the nanners better.

Pineapple express auto pollen

• Blazinjones
• Nov 4, 2018

Pineapple express auto pollen

• Blazinjones
• Nov 4, 2018

This is after i snipped the nanners off an scrapped it into a pile.

Pineapple express auto pollen

• Blazinjones
• Nov 4, 2018

 

[Pennywise]

I put it in a small tube with a few grains of rice and store in the freezer.

 

[Pennywise]

@Blazinjones remember that water will kill pollen.

 

[TorturedSoul]

This is after i snipped the nanners off an scrapped it into a pile.

Pineapple express auto pollen

• Blazinjones
• Nov 4, 2018

In theory, probably 25,000+ potential seeds' worth of pollen in that little pile. That's why people tend to mix pollen with flour (etc.) - each of those tiny grains can fertilize one female flower - but it's pretty much impossible to apply ONE of them to a female flower. Or five, or ten, or... So people cut it. You still end up over-applying, just not so much, so it goes farther.

By the way:

So now this time with the sts im doing 2 autos and 1 photo. The autos are pineapple express and c4 from fast buds and then the photo is devil's carnival so wish me luck every1.

If that DC is the cross that Canna Montana and Nismo12 produced, it'll have the recessive auto-flowering gene in it, so you'll end up with a mix of both photoperiodic and autoflowering plants (seeds) if you cross that with an auto. <SCRATCHES HEAD> Seems like I read that they were going to do some work with it to try to end up with a reliably autoflowering cross. But I might be misremembering, and it looks like they haven't visited the forum in a while, so it might be pointless to ask them. I do believe that more than one generation of the cross got released, though (although, again, it is possible that I'm not remembering correctly).

I have one or two of those seeds in my collection. I've thought about using it in a cross with an auto variety, but it would be inconvenient to not know ahead of time which of the resulting seeds would automatically flower and which wouldn't, because I mostly have just the one space for cannabis growing. But I'm saving it for when things change in that regard (and hoping it'll still be viable at that time).

 

[Blazinjones]

I put it in a small tube with a few grains of rice and store in the freezer.

Awesome thanx man an how long do i let it sit out 2 dry? I dnt want any moisture in there when i put it in the freezer.

 

[Blazinjones]

In theory, probably 25,000+ potential seeds' worth of pollen in that little pile. That's why people tend to mix pollen with flour (etc.) - each of those tiny grains can fertilize one female flower - but it's pretty much impossible to apply ONE of them to a female flower. Or five, or ten, or... So people cut it. You still end up over-applying, just not so much, so it goes farther.

By the way:



If that DC is the cross that Canna Montana and Nismo12 produced, it'll have the recessive auto-flowering gene in it, so you'll end up with a mix of both photoperiodic and autoflowering plants (seeds) if you cross that with an auto. <SCRATCHES HEAD> Seems like I read that they were going to do some work with it to try to end up with a reliably autoflowering cross. But I might be misremembering, and it looks like they haven't visited the forum in a while, so it might be pointless to ask them. I do believe that more than one generation of the cross got released, though (although, again, it is possible that I'm not remembering correctly).

I have one or two of those seeds in my collection. I've thought about using it in a cross with an auto variety, but it would be inconvenient to not know ahead of time which of the resulting seeds would automatically flower and which wouldn't, because I mostly have just the one space for cannabis growing. But I'm saving it for when things change in that regard (and hoping it'll still be viable at that time).

Yea its the dc from them an no im not guna take tht pollen an put it with my autos or vice versa. What im guna do with the dc pollen is put it on another dc i have going an make some dc beans. But i also have some auto pollen tht im collecting up 2night from a pineapple express auto then 2morow ill collect some from my c4 auto also.

 

[Pennywise]

That's why I use rice grains to draw the moisture from it.

 

[Blazinjones]

That's why I use rice grains to draw the moisture from it.

So do u put it in the container with the rice right away then or do u wait?

 

[Pennywise]

Yes that's the way I do it, if you want to let it sit for awhile make sure it's a dry place.

 

[Blazinjones]

Yes that's the way I do it, if you want to let it sit for awhile make sure it's a dry place.

Ok thanx man so much for the help. Ive been trying so hard to make auto pollen with my red poison auto beans i had from sweet seeds. An they wudnt work out either shooting blanks n each sac was empty or it wudnt even make sacs/nanners but tht was when i was using colloidal silver spray. Now im using the sts an every plant i started using it on so far has made pollen well atleast the autos have. Im also making pollen from 2 photo strains i have going currently 1 is the devil's carnival an the other is blue cheese both of which are in flower now jus starting to make buds. So it shud be really soon an then ill see some sac if it took that is lol. Also if u can help me with this as well i would greatly appreciate it. 1 do u happen to know how long the pollen will last if i keep it in a ziplock baggie with some rice in the freezer? And 2 will this rice work its long grain brown rice? And then last but not least if i was to add flour to my pollen to make it stretch out how much flour should i add to it?

This is the rice i have in question?

20181106_003152.jpg

• Blazinjones
• Nov 5, 2018

 

[Pennywise]

The rice should work for you, I've heard different stories about how long pollen will stay viable in the freezer but I would think a year or more. The trick is to keep dry. I mixed my pollen with flour 50/50.

 

[Blazinjones]

The rice should work for you, I've heard different stories about how long pollen will stay viable in the freezer but I would think a year or more. The trick is to keep dry. I mixed my pollen with flour 50/50.

Ok thanx well with my pineapple express auto i got so much dam pollen i dnt need to cut it lol. But my c4 auto i mite do tht since it didnt produce as much an i really really wana do some experiments with this strain so more pollen the better right lol.

 

[Pennywise]

Flour will let you spread it farther no problems.

 

[Blazinjones]

Flour will let you spread it farther no problems.

Awesome ill be adding tht in with the c4 auto pollen i have then. Cause i didnt get as much as i thought when i seen how much the pineapple express auto gave i figured the c4 wud b just as much but 1 i didnt spray as many branches dwn with the sts on the c4 as i did the pineapple. And 2 the c4 dont have as big of yields as the pineapple express do so far every single p.express ive done has yielded huge. But the c4 is a strain i wanted to preserve more cause it produces frostier buds an is just amazing for oil an concentrates. But yea i used some of the c4 pollen an dusted buds on like 3 or 4 branches of my pineapple express auto #2. Thts the one tht is turning into a super auto. Even my pineapple express #1 tht didnt get super huge like the rest still had a rediculous amount of bud so i wud still consider all my pineapple autos ive ran so far from fast buds seeds have turned to what i wud say is a super auto. They end up just as big as some of my photos an i usually pull anywhere from 3 to 4 zips so for an auto thts pretty good imo. Maybe to better growers thts not tht good but for me its great lol. Wen i wud do autos in soil organic or synthetic i wid usually only get about a zip maybe 1 ana half zips if i was lucky lol. I plan to try an auto with the hb kit soil an see how gud tht does. And ive got one going now using dyna gro nutes to see what i can pull from each method then whatever one turns out better ill do my autos that way lol.

 

[Pennywise]

Sounds good, the 2 Brooklyn's produces over a pound using Dynagro nutes.

 

[Slowpuffer]

Sounds good, the 2 Brooklyn's produces over a pound using Dynagro nutes.

Great thread Pennywise,
So what's the verdict ? How are these selved seeds working ? You've had time now to make several cycles, and just wondering how it worked out for you. Keep it green !!

 

[Pennywise]

The S1’s work out well, just have to remember that there’s a fair amount of diversity.

 

[Old Salt]

I had a lot of questions regarding STS. Since I can only work about 15 min, with a 45 min rest period I did some research on STS, including how to make, use, and store it. Here are my preliminary findings...

How STS Works:
Silver Thiosulfate (STS) is commonly used to block the action of ethylene in plant cell cultures. Ethylene is a hormone that is present in the gaseous state. Ethylene increases during senescence (aging, flower development) and ripening, and has been shown to increase in plant cell cultures due to wounding or the presence of auxins. Silver nitrate may be used alone to block the action of ethylene but it is not transported as well as STS thus is seldom used alone.

STS is the most commonly used compound, for creating stable feminized cannabis pollen. While it is not the only method, it is arguably the most commonly used and is quite reliable. Female cannabis plants require ethylene production to form female flowers. STS suppresses ethylene production in the plants, so they will produce male flowers. As the genetics are totally female, the pollen used on female flowers will result in about 99.9% female seed.

How to Make STS:
Most sources agree on the 1:5 ratio of Silver Nitrate to Sodium Thiosulfate. Some use a 1:4 ratio. Several sources state that metal implements should not be used while making STS. Some sources mention that the silver nitrate solution and STS will stain almost anything they come in contact with. I have verified this. Wear gloves and cover your work surface with wax paper. All sources agree that Silver Nitrate and Sodium Thiosulfate should be dissolved separately in distilled water. (Note: Use distilled water, or water from an RO with a de-ionizer. The TDS must be below 5 PPM. Never use tap water, as the silver nitrate and sodium thiosulfate will bond with compounds in the water rather than with each other.) Some sources use a more concentrated Silver Nitrate solution, but in the end the solution sprayed on the plants has identical silver content. Both the concentrated and diluted solutions should be clear. If they have turned brown, they should be discarded. Many sources recommend the addition of a surfacant to the diluted solution. Yucca extract is often used, although dish detergent is also an option.

How to Use STS:
There is a wide range of instructions for the use of STS. Some start application of STS three weeks before switching to 12/12 lighting; others start two weeks after the switch. This thread is the only one recommending a single application. Other sources recommend up to once every five days for five weeks.

How to Store STS:
The dry chemicals can be stored in a cool, dark place indefinitely, as can parts A and B before they are mixed together to form the concentrate. One source states that the concentrate can be stored in a cool, dark place for up to nine months, but will have degraded somewhat by that time. Other sources state it should be used within a month or two. Most sources agree that the solution diluted for application to the plants should be used within a week or two.

 

[Pennywise]

Yes that’s the tutorial most of us started with.

 

[Rows Of Green]

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)

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.

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.

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.

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.

A Google search will bring up more information if needed.

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.

Have fun experimenting with this technique. Use it responsibly. There are a few good threads here at CW that go into the pros and cons of transsexual agents and feminized seeds. Read them. And most importantly, use STS with quality F1 strains developed by professional breeders for the most consistent results.

A huge thanks to Fet from Spice Brothers Seeds for his help and advice in using this technique. I simply brought together available information from previous posts and tried my own recipe. I'm thrilled to share the results. Future tests will be done to adjust the formula so the molar ratios of the chemicals are correct, as specified by Gobgoober (thanks, Gob) but the formula posted here is completely effective.

Great post