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 double
Diesel
Registered: 02/12/11
Posts: 207
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 making seeds from partial harvest question 
#549643 - 04/23/11 03:44 AM (13 years, 6 months ago) |
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I've got this question:
can I partially harvest a female flowering plant and then pollinate the flowers left to get seeds?
or do I have to leave just some leaves and then revert back to vegetative state?
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 alienscience
Farve in training
Registered: 01/04/11
Posts: 478
Last seen: 4 years, 3 months
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Re: making seeds from partial harvest question [Re: double]
#549646 - 04/23/11 04:27 AM (13 years, 6 months ago) |
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You can actually do this. You can either pollinate with pollen from a different plant (other than the one harvested) or let the plant continue to flower until it rodelizes. The method is called rodelization. It occurs when a plant is stressed by flowering longer than normal and hermies; therefore self pollinating. This method produces female seeds, but you need to collect the hermy pollen from your rodelized plant and pollinate a different plant that is early intothe flowering stage to get viable seeds. It's a little bit weird of a tek, but it apparently works.
http://hightimes.com/grow/soma/622
If you only have one plant after your harvest, I'd recomend either pollinating the leftover buds (still intact and growing) or reverting it back into veg; which can be done. And growing it out again before pollinating. Pollinating full buds will only cause the plant stress and make it hermy. You could always put the leftover plant outdoors in the earth and wait until fall to harvest it.
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Magash
The Feminizer
Registered: 04/21/08
Posts: 6,634
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Re: making seeds from partial harvest question [Re: double]
#549649 - 04/23/11 05:22 AM (13 years, 6 months ago) |
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For somebody to do it at home use one of these methods.
This is from Rez the breeder and owner of Reservoir Seeds https://www.icmag.com/ic/showthread.php?t=58957 I have used this method a thousand times at the very least and it is the standard way of doing feminized seeds in the seed industry.
Then there is CS which is the easiest for the home seed maker and works pretty damn well also. https://www.icmag.com/ic/showthread.php?t=60610 ;
There is also Soma's method (Rodelization) of just leaving the buds on the plant way past their maturity which most strains will start to put out male flowers under age stress. This method is almost guaranteed to give you a good percentage of hermie plants and really shouldn't be used. Which explains the high percentage of complaints with Soma's feminized seeds.
and one that covers them all https://www.icmag.com/ic/showthread.php?t=199540
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All creatures tremble when faced with violence. All creatures fear death, all love life. If we can only see ourselves in others, then how could we possibly hurt another creature?
 Join us at the Growery!
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double
Diesel
Registered: 02/12/11
Posts: 207
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Re: making seeds from partial harvest question [Re: alienscience]
#549650 - 04/23/11 05:32 AM (13 years, 6 months ago) |
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Quote:
alienscience said:
Pollinating full buds will only cause the plant stress and make it hermy.
I see. thanks for the article. so pollinating a ripe amber female bud with either male or female pollen is not a good idea or won't it work AT ALL? 
'cos from what I understand about rodelization one should need at least 2 female plants:
a yet ripe female to get some female pollen from and use it on another female plant which is though not yet ripe to harvest. would this mean that ripe buds can no longer make seeds even if pollinated?
thanks alienscience!
edit: thanks magash for your input as well!
Edited by double (04/23/11 05:35 AM)
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alienscience
Farve in training
Registered: 01/04/11
Posts: 478
Last seen: 4 years, 3 months
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Re: making seeds from partial harvest question [Re: double]
#549683 - 04/23/11 08:57 AM (13 years, 6 months ago) |
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They might develop seeds, but I think they won't mature until way past your harvest time. And that will probably cause them to rodelate(?); or in other words "hermy".
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double
Diesel
Registered: 02/12/11
Posts: 207
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Re: making seeds from partial harvest question [Re: alienscience]
#549695 - 04/23/11 09:57 AM (13 years, 6 months ago) |
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I see your point. also self pollinating the same plant would bottleneck genetics which is a bad thing.
if using gibberellic acid on a female plant to have it set male flowers, which solution strength ppm would you suggest? also would it need to be sprayed before it flowers or during?
thanks ya all
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Magash
The Feminizer
Registered: 04/21/08
Posts: 6,634
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Re: making seeds from partial harvest question [Re: double]
#549785 - 04/23/11 02:34 PM (13 years, 6 months ago) |
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Read up on colloidal Silver. Safer (as in non-toxic) then gibberellic acid and works better, last but not least it's also cheaper. 
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All creatures tremble when faced with violence. All creatures fear death, all love life. If we can only see ourselves in others, then how could we possibly hurt another creature?
Join us at the Growery!
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alienscience
Farve in training
Registered: 01/04/11
Posts: 478
Last seen: 4 years, 3 months
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Re: making seeds from partial harvest question [Re: Magash]
#549833 - 04/23/11 05:02 PM (13 years, 6 months ago) |
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Gibberalic acid needs to be applied every day for the first 10 days of pistil formation. I've got some CS coming in the mail too, and that has to be applied for the same amount of time. The tricky part is collecting the pollen and using it to pollinate another plant without getting any of the CS/Gib material on the new plant as it is unsmokeable and can ruin the bud. Collodial Silver is basically a metal solution suspended in water so it'd be like smoking shrapnel. I know the PPM concentration for CS applications need to at least be 30ppm, but I am unsure of the GB solution.
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double
Diesel
Registered: 02/12/11
Posts: 207
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Re: making seeds from partial harvest question [Re: alienscience]
#549843 - 04/23/11 05:11 PM (13 years, 6 months ago) |
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what about the silver thiosulfate? same process each day for 10 days?
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alienscience
Farve in training
Registered: 01/04/11
Posts: 478
Last seen: 4 years, 3 months
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Re: making seeds from partial harvest question [Re: double]
#549883 - 04/23/11 08:01 PM (13 years, 6 months ago) |
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STS actually reverses the sex of a female plant into a male one. The only info I could find on it was that it needs to be applied once before going into 12/12. Here's a link to a nice article.
http://forum.grasscity.com/indoor-marijuana-growing/121993-feminizing-using-sts-instructions.html
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Magash
The Feminizer
Registered: 04/21/08
Posts: 6,634
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Re: making seeds from partial harvest question [Re: alienscience] 1
#549903 - 04/23/11 08:32 PM (13 years, 6 months ago) |
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Ok, so ya wanna know about STS
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.
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.
I wanted to add a few quick observations about STS.
First, the strength listed is meant to be used with "fresh" silver nitrate. It's important to understand that silver nitrate loses it's activity over a period of 6 months to a year, even in the refrigerator.
So - after your sn (in crystal form) spends 3 months in the fridge, I'd mix your spray solution at 5:1; after 6 months, go to about 3:1; after that, hit them with the full strength stock solution, or better yet, get a new batch of silver nitrate. Don't forget to use distilled water; that part is important.
I have not noticed any problems with the sodium thiosulfate going bad; I'm still using the batch I originally bout over 2 years ago with no problems.
Also, different plants respond differently to STS; some need to be hit harder than others. I would venture to say that 1:9 is the weakest you should go. Look for a burning of the leaves; if you see it you need to lighten up a bit next time.
A second spraying is absolutely critical to success; I actually hit my F>M plants every week for 4 weeks, at which time they are usually ready to start dropping pollen. An exception would be any plant where you see some burning of the leaves.
Another important aspect is to give your F>M all of the nutrients that other plants get during flowering. Don't skimp on the bloom ferts. Liquid Karma seems to help, too.
Finally, temperatures in the mid-80s seem to be optimum for final maturation of the male blooms. Some strains will stall at the end of the process and fail to finish; the flowers never finish maturing. These strains may need to be hit a bit harder with the STS, or may need more warmth to complete their mission.
I have tried many different colloidal silver approaches, using commercially available versions and also making my own using silver ingots at various DC voltages. I have never had any luck with it. Getting a consistent ppm of cs can be tricky; I never saw the point, as silver nitrate is cheap as hell and easy to use. And safe.
Just another quick note. Some plants are more stubborn than others to treatment at the 1:9 spray ratio. Don't be afraid to ramp up the concentration if you don't see a slight effect on the leaves. The sweet spot seems to be just about when the leaves show some minor signs of stress, but not too much. And yes: hit your target plant twice or even 3 times.
1:5 is about right for any silver nitrate crystals that has been in your fridge for 6 months or so. After a year of storage the activity in the silver nitrate is so low that you should re-order.
As for sn being "regulated"... it sort of is, but there are definitely sources on the internet that offer it in 10 gram quantities, and without scrutiny from authorities. Likewise, sodium thiosulfate is widely available online.
But there is a caveat: do not order silver nitrate AND sodium thiosulfate from the same supplier: the DEA is still watching people that do this. Unfortunately my original publishing of my STS technique on the old Cannabis World (same as it is seen here, almost verbatim) had a direct link to Photographer's Formulary, and the end result was the DEA's full attention. Sorry about that.
I'll chime in once again about the "safety factors" debate regarding silver nitrate, sodium thiosulfate, and the resulting STS. The people who are harping about the "dangers" are very likely the same people who used to sell EXE, that overpriced commercial version of STS.
Use common sense and read the MSDS and you will see that it is fairly silly to worry about using it.
STS (including it's individual component ingredients) is very safe to mix and work with. As long as you follow some simple guidelines, you'll be fine.
Silver nitrate should not be breathed as it is caustic. It is really no more dangerous than any chemical fertilizers in this regard. Just use a dust mask if you are concerned. If you are concerned enough to wear a mask for silver nitrate, definitely wear one while mixing fertilizers, as this is far more caustic.
The original source for the information
Mohan Ram & R. Sett, who actually wrote the article "Induction of fertile male flowers in genetically female Cannabis sativa plants by silver nitrate and silver thiosulphate anionic complex." in Theoretical Applied Genetics in 1982.
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All creatures tremble when faced with violence. All creatures fear death, all love life. If we can only see ourselves in others, then how could we possibly hurt another creature?
Join us at the Growery!
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double
Diesel
Registered: 02/12/11
Posts: 207
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Re: making seeds from partial harvest question [Re: Magash]
#553230 - 05/05/11 07:34 AM (13 years, 6 months ago) |
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could two cuttings of the same female plant pollinate each other (and set feminized seeds) if one of them is forced to set male flowers by the above methods?
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c99hunter
Registered: 12/12/10
Posts: 304
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Re: making seeds from partial harvest question [Re: double]
#553255 - 05/05/11 11:41 AM (13 years, 6 months ago) |
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Quote:
double said:
could two cuttings of the same female plant pollinate each other (and set feminized seeds) if one of them is forced to set male flowers by the above methods?
Pretty sure that's how it's done 
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Cannasaurus
Pollen Chucker
Registered: 09/18/10
Posts: 76
Loc: Colorado 
Last seen: 13 years, 3 months
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Re: making seeds from partial harvest question [Re: double]
#553279 - 05/05/11 01:00 PM (13 years, 6 months ago) |
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Quote:
double said:
I've got this question:
can I partially harvest a female flowering plant and then pollinate the flowers left to get seeds?
or do I have to leave just some leaves and then revert back to vegetative state?
Yes and no. If you wait too long the seeding window will close and there will be less viable ovules to impregnate.
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"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius -- and a lot of courage -- to move in the opposite direction."
-Albert Einstein
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double
Diesel
Registered: 02/12/11
Posts: 207
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Re: making seeds from partial harvest question [Re: Cannasaurus]
#561636 - 06/03/11 06:24 PM (13 years, 5 months ago) |
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the simplest method would be to let a plant go hermie, and unless using male-like pollen from another female plant (which doesn't come from the same mother plant) I don't see any benefits in improved genetics.
that myth of feminized hermie seeds yielding hermie plants was discussed as myth on cannaculture if I remember right.
loosely staying on topic, can you revert to veg and keep a rodelized or CS treated plant?
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OrgoneConclusion
Stranger
Registered: 05/06/11
Posts: 93
Last seen: 6 years, 10 months
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Re: making seeds from partial harvest question [Re: double]
#561916 - 06/04/11 06:00 PM (13 years, 5 months ago) |
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Here is the OC method:
Had one male and two female plants in a 2' * 2' area. Cut the male plant back to almost nothing during flowering. It grew out and I trimmed it hard again so there was too little pollen to go around. Got enough seeds (about a hundred) to last me years and yet most (70-80%) of the bud was seed-free. Best of both worlds, baby! 
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