Tony's silver thiosulfate notes

[Douglas.Curtis]

I've updated the first page to include that info, thanks for pointing out it was missing.

You'll see the pods swell up and then begin showing stripes as the sepals begin separating. Striped, fat footballs. Most 60-70 day strains will shower pollen within 3 weeks of the beginning of flower, and definitely within 4 weeks.

You'll want to leave seeded flowers to grow for a minimum of 5 weeks, preferably longer.

 

[RottyRzr]

I've updated the first page to include that info, thanks for pointing out it was missing.

You'll see the pods swell up and then begin showing stripes as the sepals begin separating. Striped, fat footballs. Most 60-70 day strains will shower pollen within 3 weeks of the beginning of flower, and definitely within 4 weeks.

You'll want to leave seeded flowers to grow for a minimum of 5 weeks, preferably longer.

Very helpful!
Thanks for the info

 

[QWETminus60]

Tangie auto flower STS sprayed eight times starting day20… Male flowers developing after day 50
Currently day 75. I almost gave up weeks ago.
We’ll see ???
Sorry to butt in on the thread, but thought it was interesting how late this auto finally converted…
I’m switching over to photos in the future!

 

[Douglas.Curtis]

8 sprays is quite a bit... hoping you get viable pollen dropping before it runs out of gas to make more pods.

Autos have their uses.

 

[beta]

Has there been a consensus yet on whether or not hard-to-reverse cultivars like Diesels need a higher or lower concentration than 3mM?

 

[Carraxe]

I've used the OP method, but directly: I dissolved 0,1g of silver nitrate in half a liter of water and 0,8g of sodium thiosulfate 5-hydrated in the other half a liter, and once dissolved I just mixed the liter and sprayed. I believe the mixture can be conserved for months with just some drops of ammonia, since it is stable in alcaline pH. If not, progressive decomposition of the mixture will produce a very special tinge from colloidal silver in the coming weeks.

I sprayed about 5 times over a Jack Herer, every 4 days in average, since flip, one month ago and I got a very good male blooming. That would be a 0.5mM concentration.

Thanks OP for these numbers.

 

[pdub]

Has there been a consensus yet on whether or not hard-to-reverse cultivars like Diesels need a higher or lower concentration than 3mM?

you really need to be putting things onto the sour not using the sour as a pollen donor.Due to the fact that it will pass on traits you don't want (herms)

 

[GreenamI]

This thread is to document my sts notes. I'm gonna try a few things.

Study on storage of sts.

https://www.sciencedirect.com/science/article/abs/pii/0304423885900093

Dilution calculator:
https://www.tocris.com/resources/dilution-calculator

Foliar Sprays of Silver Thiosulfate Produce Male Flowers on Female Hemp Plants
in HortTechnology

Authors: Jessica D. Lubell 1 and Mark H. Brand 1

https://journals.ashs.org/horttech/downloadpdf/journals/horttech/28/6/article-p743.xml


Pollen Appearance and In Vitro Germination Varies for Five Strains of Female Hemp Masculinized Using Silver Thiosulfate
Jessica DiMatteo, Lauren Kurtz, and Jessica D. Lubell-Brand

https://journals.ashs.org/hortsci/view/journals/hortsci/55/4/article-p547.xml


PREPARATION OF SILVER THIOSULFATE (STS) SOLUTION

Sigma-Aldrich:
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 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.

Prepare a 0.1 M Sodium Thiosulfate (STS) stock solution by dissolving 1.58 g of Sodium Thiosulfate anhydrous or 2.48 g sodium thiosulfate pentahydrate(x1.56) into 100 ml of water.

Prepare a 0.1 M Silver Nitrate stock solution by dissolving 1.7 g of Silver Nitrate into 100 ml of water. Store the stock solution in the dark until needed to prepare the STS.

The STS solution is prepared with a molar ratio between silver and thiosulfate of 1:4, respectively. Nearly all of the silver present in the solution is in the form of [Ag (S2O3)2]3-, the active complex for ethylene effect inhibition.

Prepare a 0.02 M STS by slowly pouring 20 ml of 0.1 M silver nitrate stock solution into 80 ml of 0.1 M sodium thiosulfate stock solution while stirring vigorously.The STS can be stored in the refrigerator for up to a month. However, preparation of the STS just prior to use.

Dilution strengths quick reference:

100 ml .02 M sts solution at:

20mM straight stock
15mM add 33 ml water
10mM add 100 ml water
6mM add 233 ml water
5mM add 300 ml water
4mM add 400 ml water
3mM: add 557 ml water
2mM add 900 ml water
1.5mM add 1230 ml water
1mM add 1900 ml water
.5 mM add 3900 ml water
.3mM add 6570 ml water

I did some math for adjusting the sigma recipe for no left overs: for 300 ml .02M sts the recipe is

1.0192 grams silver nitrate in 60 ml water
And
5.9566 grams sodium thiosulfate pentahydrate in 240 ml water
Or
3.7946 grams sodium thio anhydrous in 240 ml water

Seems cheap scale friendly. Penta friendly (most readily avail) and you dont have leftovers that you have to mix more to use.

If anyone wants to check my math or sees an error let me know!

Although the reply is a far overdue, I decided to I re-run your maths still and it seems pretty solid. We have been using the same recipe, diluted to 3mM. I only added tween 20 in the end at a rate of 0.1% to act as a surfactant (i.e., 10 ml/L). We never had an issue with pollen formation, however the success was very cultivar dependent and I only tried it on three different strains so far (before we used colloidal silver). SD was the only plant to show very minimal pollen formation, but a fan still caused successful fertilisation (I've read the discussion about the SD in this thread). Other plants where shedding clouds like regular males. For application we sprayed onto the entire plant at the time of switching to flower (or at the initial signs of flowering for auto's), and repeated this weekly for three weeks.

 

[Hotrods_and_hounds]

Although the reply is a far overdue, I decided to I re-run your maths still and it seems pretty solid. We have been using the same recipe, diluted to 3mM. I only added tween 20 in the end at a rate of 0.1% to act as a surfactant (i.e., 10 ml/L). We never had an issue with pollen formation, however the success was very cultivar dependent and I only tried it on three different strains so far (before we used colloidal silver). SD was the only plant to show very minimal pollen formation, but a fan still caused successful fertilisation (I've read the discussion about the SD in this thread). Other plants where shedding clouds like regular males. For application we sprayed onto the entire plant at the time of switching to flower (or at the initial signs of flowering for auto's), and repeated this weekly for three weeks.

By repeating you mean whole body plant once a week?

 

[GreenamI]

By repeating you mean whole body plant once a week?

Yes, spraying the whole plant, once a week, three weeks in a row

 

[Yagar2000]

Hi all I have a question for those who have already managed to reverse a plant I see that in the second technique that the author proposed there is marked a ratio of 1:9 this is for the final solution for example 10ml of sts for 90ml of water or is it for the dosage of solution A and B as for the aldrich sigma recipe? 10ml of silver nitrate for 90ml of sodium thiosulfate. I'm starting to get a little confused because the two techniques are very different in their dosage. I would be more willing to try the Sigma recipe, which do you think is the best recipe? I'm blooming today

 

[RizlaMan]

Hi all I have a question for those who have already managed to reverse a plant I see that in the second technique that the author proposed there is marked a ratio of 1:9 this is for the final solution for example 10ml of sts for 90ml of water or is it for the dosage of solution A and B as for the aldrich sigma recipe? 10ml of silver nitrate for 90ml of sodium thiosulfate. I'm starting to get a little confused because the two techniques are very different in their dosage. I would be more willing to try the Sigma recipe, which do you think is the best recipe? I'm blooming today

The 1:9 dilution is for sts:water.

In my limited experience both concentrations, diluted 1:9 or full strength, are efficacious.

 

[Yagar2000]

The 1:9 dilution is for sts:water.

In my limited experience both concentrations, diluted 1:9 or full strength, are efficacious.

Thank, I managed to reverse the sex of my plants. I used the recipe from the forum undiluted for the first sprays on the first day of 12/12. I was treated to a nice burn on some leaves which were affected by the STS. I didn't know if this recipe was really operational since there is still quite a difference between the sigma recipe so the 2nd spray (1 week after the 1st sprays) was made with the sigma recipe diluted to 0.5mM shortly after I already saw male flowers, I repeated the sigma spray at 0.5mM a week after the 2nd which will be the last spray with the harvest of the male polen. I have an almost total reversion, I don't know if it's due to the first spray from the undiluted forum but for the moment it looks good in 2 weeks when the effect of the STS will have worn off and the ethylene will have returned in the plant I would be at the 3rd week of flowering just perfect to be able to fertilize my other clones