“The sexual expression of cannabis is determined by its genetic makeup, and by its metabolic temper, which is regulated by the male enzyme andrase and the female enzyme gynase. Environmental conditions (light, nutrients, soil and water) may suppress the formation of the dominant enzyme, and allow the opposite sex to express itself partially (hermaphroditism) or completely (sex reversal).”
External influences AND introduction of hormones can influence sexual expression in cannabis and is for sure not set in the seed. Seeds introduced to ethylene gas for long periods are known to increase female ratios by up to 50%
We’re getting into genotypic or phenotypic sex here. I am talking about genotypic sex, namely the presence or absence of a Y chromosome.
Cannabis clearly shows extensive levels of intersexual characteristics, but I’ve never heard of full sexual reversal occurring except when external chemical means are used. If it was common at all, we would see fem seeds coming from seemingly “male” pollen donors, and we don’t.
Regardless, even if full sexual reversal were to occur, taking a cutting from the same plant and growing it under ideal conditions, the plant’s sex will reflect the chromosomes present. For all reasonable circumstances, the plant’s sex can be boiled down to whether or not it has a Y chromosome.
Essentially this is true. Not as simple as this since it can be many factors that affect the sexual expressions. But the other difference to note which seems to be misunderstood is that cannabis isn’t just diploidy (two sets of chromosomes), but can be a polyploidy. (More than two sets)
Is there a conclusive case of polyploids in cannabis? Everyone calls fasciation or whorled phyllotaxy polyploids, but that’s incorrect. Plus, in the vast majority of plant species, polyploids cannot be bred with, so that point is moot.