Understanding breeding, how to achieve the best an strongest high, false beliefs an inbreeding depresion

Hello folks i thought it was time some of us discus breeding methods. I especially wanted to open up dialogue surrounding issues of one to one breeding vs open pollination an the actual uses for these things as well as inbreeding depression an how or why it comes about. Its seems that many people have a false belief regarding some of these issues an this thread may be useful for many people who want to try to breed the best along with getting high quality an potency from the seeds you breed even when germinated in small numbers. Also understanding how an why degradation or inbreeding depresion comes about.

Ok something i think may be useful in getting people to easily understand what I’m trying to do here. So for example many people are looking for highly potent, electric, trippy sativas (this could be used for heavy potent indicas or just outstanding scent or flavours)an don’t understand why they are no longer found in the way they once were. If you can imagine we have a field of eg Thai sativas. There are 5000 plants in this field. Maybe 30% are male an 70% are female (this is just for example so that people start to get the picture). These plants are left to go full season an openly seed in the outdoor conditions. Now the first question #1 is once the seeds were all collected an next year grown out an we were looking for the most trippy electric plants why would all the plants not be overwhelmingly potent plants equally ? #2 Why would only a certain probably 10-15% of the plants be better that much better ? #3 An then once those plants are found how do you recreate the next generation of seed to be at the same quality as those ? I will leave it there as a starting point.


I’ll bite.

First, every breeding is one to one. Each seed only has two parents. Open pollination just means you no longer know who the father is.

The best lines have come from heavy selection.

For your questions:
In an open pollination setting, especially with a landrace, the males and even the females will flower at different rates producing a wider range of genotypes. Also, you’ll usually have plants ranging from high cbd/low THC to high THC/low cbd. Even if no cbd, you’ll have plants with varying THC and other cannabinoid rates.

The general consensus would be that early flowering males are usually worse and will pollinate everything first, while the later flowering males will cover what’s left. What’s left is likely “~10-15%” of the beans. I’d say further there’s something to be said for Punnett Squares and specific combining ability due to what I stated in question 1. If there’s a spread of cbd/THC rates in the line and its an open pollination, you’ll likely only have less than a third of the following generation that will be better than the previous gen.

#3 You only plant seeds that were collected from the best females of the previous year. Grow em, make your male selections, pollinate, collect from the best females again, rinse, and repeat. This is how most legendary landraces were cultivated and improved over time. Also haze, skunk, blueberry, and more…

Better idea imo if you have the space and plant count, is to keep the males that meet your goals and track each girl each male hits, don’t just throw pollen from all of them at once. Grow out and track the offspring of each pairing. Then decide which male(s) to use with which female(s) to further the line. You might get more than one pair.


Sounds like years of testing and note taking! So many combinations to run thru. Seems as if one could run into some hybrid vigor and get sidetracked from the original goal.


Plant breeders could learn a lot of lessons from dog breeders especially about inbreeding depression. Basically you can lock traits down and creat unique and often impressive lines but you need to outcross some generations or things quickly fall apart. Picking out crosses that fit well with the already established and desired traits along with selection is a powerful tool. People get stuck on keeping a line pure and it takes a large population to do that and avoid bottlenecking the gene pool. Besides with the way alleles work you really can’t keep things the same anyways and the recessive crap genes tend to combine and become dominate.
A attractive dumb girl once told a ugly smart guy they should have kids so they could have her looks and his brains , he replied what if they have my looks and your brains.


Wonderful discussion, exactly what I love about Overgrow and all the great minds. Nothing to contribute but my thanks and learning.


This is gospel as far as I understand genetics. On a whole whether a human, animal or plant genetics itself changes little.
Inbreeding causes a lack of vitality and creates an environment where recessive genes become dominant and can lead to progeny that are more open to disease and less viability.
For example we all know what happened to the line of the pharaohs where incest was not only common but demanded to keep that lineage “pure”. What they ended up with after many generations was King Tut which had deformities and died at a young age. He also married his sister who was not able to have surviving children (two stillborn).
Outcrossing can increase vitality and lead to new developments in that genetic line.


Someone’s mentioned punnet square, glad to see that. Those that look into that, or Mendels pea experiment will see you dont need to pop 1000s of plants, even 100 is unnecessary overkill if the parents were worked.
There’s 2 approaches being discussed Op, one is outdoor regional acclimatization. That population will self sustain and survival of the fittest is the law of nature. Thats ur 10-15% kickass stuff. You need more than 3-5yrs and you do not get to walk in there and select stuff you like. You can select starting parents, but after that you don’t interfere. This is outdoor discussion
The other point is recreate next gen to be of equal quality, that’s a homozygous population (f6)once you’ve found the kickass parents you want to run, you just keep mom and dad in clone form and constantly pollinate…there is no genetic degradation, cuz you’re not breeding further or outcrossing. There would be a couple of phenos maybe, Punnet Square, but not many if you did it right…you can even remove those last errant phenos if you try.


I was actually thinking of the pea experiment while reading the above. Great minds! Very well said, this thread is highly intriguing


I think it was on an episode of the Pot Cast, probably with Chimera… They said, get a general introduction book to plant breeding and avoid everything that focuses on cannabis as it is full of bro and stoner science. That’s what I did, hope to find time to read it too. :nerd_face:


Like breeds like, but not exactly alike :wink:

Pay close attention to your plants.

Every single vegetable has been created by careful selective breeding. Just look at Broccoli. Cabbage, cauliflower, kale, brussels sprouts, collard greens, and kohlrabi, are all Broccoli. All come from the exact same mustard plant that has been selectively bred for different singular traits resulting in those plants we call by different names, even though genetically they are all the same exact species.


“The general consensus would be that early flowering males are usually worse”

I have not found any study saying this.


There isn’t any study really that I’ve seen, but its the words of most breeders I’ve spoken with or read from, like DJ Short and others. Most will tell you the early flowering males generally give less potency, more fiber production, herm/autoflower traits, and generally will drag your line down.

There’s other, old talk of, if you put a bunch of seeds of any strain out in a field and come back in 5 years, its going to be significantly worse overall. Well, the males that flower early WILL produce more seeds, so if the line does go down over time by letting it be, that seems to infer that the early flowering males are worse than the later flowering males that would produce less seed on already pollinated females.

Uses Of Male Cannabis Plants - RQS Blog.

Just to list a few from a quick search…


What were you thinking about it?

Put down your copy of whatever book everyone else is reading. The official story is meant to be exposed, not agreed with. You probably also believe Elon Musk invented a dancing robot and that Oswald shot Kennedy.


I have read enough on chlorophyll and curing that does not measure up but is passed around as bro science. I am keeping an open mind on the males but I have not found any definitive proof of the ‘fact’.


Yeah I don’t consider it as fact either but you asked. It’s why I furthered my original statement you only partially quoted with my own thoughts with punnet squares and specific combining ability ^^


We wont until the Universities are allowed to study them for generations and that’s gonna be a while still. If it’s an IBL or f5-f6 male selection dont matter. It’s when ur messing with polyhybrids and whatnot male selection speed matters…other than that it’s just what a breeder wants. I may want a faster male for faster flowering in offspring, but i would be running the risk of introducing hypersensitive traits such as hermie prone plants…fkn controlled dangerous substance my ass.


looks like i am headed to the book store. need to do some more serious reading. what a great thread and just outstanding info for this farmer. i hope to be an outstanding farmer in my field. thanks to all the great info like this from the good people here on OG.


I looked up hemp growing and you would think if early males gives more seeds, more fiber, less thc that they would be all over it.


Hemp is grown specifically to be monoecious for seed production, and fiber production. No regard for cbd or thc when it comes to trait selections in hemp breeding.

CBD flower “hemp” has become a totally separate trait selection back to dioecious plants.


When taking on breeding projects I was taught to always stress out my males some, in order to find the “true” males rather than any herms that may present initially as male.

I’ve wondered if herms might account for some of the distrust of early males. As the shape-shifting gender, i think they tend to react to stressors quicker than non-herm prone plants.
Anecdotally, I do believe I have seen a higher percentage of the early showing males, wind up also throwing pistils when stressed, as compared to late showing males, which seem to tend more towards the stable side.