I’ve been working with natural polypoid cannabis plants for several years now and here’s some info I’ve learned:
First and foremost is the inaccurate info floating around that 3-leaves means triploid. NOT SO!
3 leaves just means tri-foliate. It may or may not be due to being triploid. So seeing 3 leaves does NOT necessarily mean you have a triploid. Only a chromo count can verify that.
Diploids (regular) plants have 2 sets of chromosomes. Cross a male diploid and female diploid and you get more diploids (1 chromosome from each parent). Basic stuff. Chart looks like this:
Note that
Females can become hermaphrodites on some plants. This is a species-saving tactic that many plants have.
Triploids have 3 sets of chromosomes - usually Tetraploid(4) x Diploid(2) cross - 2 chromes from tetraploid parent and 1 from the diploid. Chart looks like this:
Note that
MALES can become hermaphrodites on some plants. I believe this flip is due to the extra X gene.
XYY (Meta Males) – triploid males with viable pollen. If you are an Aliens fan, you’ll remember the Double-Y-Chromo-Boys in Aliens3. These are good plants but can herm under severe stress. These can be used for breeding but should be tested/proved first.
XXY (Sterile/Hermy Males) – weird situation here as these should be STERILE! I find the pollen is viable but the pistils are usually not. These plants usually show as complete, true-hermaphrodite flowers. If you have male hermy plants, they are probably these. I cull ALL these.
XXX (Meta Female) – these are the girls you are wanting! The 3 X genes can give you some incredible plants. This is where you see extreme trichome coverage, super-dense vegetation, very dark green color (excessive chloroplasts), and drink like fish (high respiration). The main word here is EXCESS! They just have more of everything. I’ve never seen one of these herm. I don’t think they can.
FYI: OG Kush, Master Kush and Acapulco Gold were all polyploids.
The biggest puzzle piece I found was when I realized triploid cannabis plants don’t always give just 1 chromo (like most triploid plants do if they are not completely sterile). Sometimes they give 2. Apparently cannabis doesn’t have a problem with the odd-number of chromosomes. Actually, it looks like they almost always give 2. Or maybe only those seeds actually develop. It's pretty common to find lots of tiny white undeveloped seeds in pollinated polyploid buds. I’m not sure what this means for cannabis but it definitely shows that this species is very changeable.
Tetraploids have 4 sets (complete doubling) with 2 from each parent. This would come from crossing 2 tetraploids or chemical treatment. Note that chemical treatment to achieve a tetraploid is not always permanent – many plants revert. The chart on this one is all over the place so I won’t show it here. Many of the chromo combinations won’t even produce a viable seed. I have never gotten a tetraploid female "naturally" and I don't know anyone that has . Not sure it’s even possible without chemicals. The XXYY male is the only one you want to keep for breeding.
