I read up on using a microscope to check the pollen viability of cannabis. The round spheres are viable ones, where the deformed and not fully formed ones are duds.
Here are the duds.
Here are the duds.
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I’d be interested in learning more, do you have a reference for us?
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I think it was this one:
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Many thanks Joe, that is a fascinating read for anyone collecting polllen.
OK, OG-Nerds, here’s the crux of Joe’s article, let’s parse the wisdoms out of it…
To explore this, we estimated the relative fitness of groups of male gametophytes in a dioecious, wind-pollinated model system, Cannabis sativa , by characterizing the non-abortion rate (measured via chemical staining) and viability (measured via in vitro germination) of pollen from multiple sires. Pollen viability quickly declined within two weeks of anther dehiscence, and pollen stored under freezer conditions did not germinate regardless of storage time. In contrast, pollen non-abortion rates declined slowly and persisted longer than the lifetime of a sporophyte plant under both room temperature and freezer conditions. Pollen samples that underwent both viability and non-abortion rate analysis displayed no significant correlation, implying that researchers cannot predict pollen viability from non-abortion rates, nor infer male gametophytic fitness from a single measure. Our work demonstrates two independent, differential approaches to measure proxies of male fitness in C . sativa .
I’ll go first… They compare two different methods used to determine what percentage of a pollen sample is capable of germination. “Non-Abortion” means that they look at a pollen sample under a microscope and count the number of deformed pollen bits. “Viability” means they count the number of pollen grains that germinate in a petri dish. In the results, they make a serious claim about freezer storage of pollen. Right so far?
Calling: @gpaw, @Reikox, @DougDawson, @LonelyOC, OGWizards&Pundits…
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Ummm… I take a look of the pollen I used recently and it is like a dehidrated sphere… Suppose that is not viable. Should have checked before trying to pollinate. 
Other stain used is “acetocarmine”.
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I know about the issues with gathering ‘late pollen’ (1st half good, 2nd half ‘meh’…).
Perhaps I’m missing their references, (eyeballs are not cooperating well this morning) but how are they prepping the pollen for storage? Conditioning (removing the RH) is the key.
Cheers
G
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Very interesting thread to check out here.
What magnification are you using to check out those pollen grains?
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10X objective .5X camera and then the magnification of displaying on your computer monitor. I think you have to multiply by the monitors DPI. Basically 1000X magnification.
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Here’s some bad news about their protocol, Quote:
“Pollen samples in centrifuge tubes were left unsealed to dry for 1hr before sealing”
I think that means that they didn’t dry their pollen samples before storing them for their freezer & room temp tests. One whole hour of drying? That’s not best practices around OG. This surprise however comes in the results:
*"Pollen stored under freezer conditions (-4°C) maintained high non-abortion rates even after 96 weeks of storage
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What did you do to that pollen to make it change like that Joe?
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Bright lights, heat and time 
It’s a killer!
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Yes… Thats the way mine look. But in light-field.
I have to take some out of the fridge to look at it and compare.
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That should work… in May… in Tucson, but the rest of us are going to need a drying box (RH < 10%) to condition the pollen.
I had a paper on that (stuck in a non-bootable computer)… 
Cheers
G
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I’m still not 100% those ones I just imaged are definitely non-viable, but based on past experience, once they look like someone stomped on a soccer ball, you don’t get any seeds.
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The part that fucking floored me was the tube the pollen makes. A tube grows out of the sphere. Fuck me, I had never thought about how the whole operation works. Imaging the shit is going to be fascinating! Oh I wonder how pollen reacts to UV light?? Can I literally hydrate this pollen on the slide? lol! So many questions.
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You summary is spot on @GrouchyOldMan, very interesting experiment. 
Pz 
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I’m still not sure i understand that part, i thought the pollen tube was anatomically from the female plant? Not clear what’s going on in that petri dish…
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Yah, those kinds of questions got my motor running. I was specifically looking for microscopic images to help me identify viable pollen, but the details in the article and photos got my brain spinning into high gear. From what I read, they used a specific mixture of compounds to get the pollen to make a tube. I want to see if that shit is true, I’ve never heard that in my f-ing life!
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There is a formula of ingredients to make it happend as “invitro”. Is another viability test, checking the lenght achieved by that “tube”. I think that I download a pdf explaining that… I will check.
Edit: sorry, I didn’t read the last post where you said that.
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