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How are Hybrids so Consistent?

I don’t understand exactly how commercial seed companies are able to produce such consistency in their hybrid seeds.

I understand how dominant and recessive gene traits work, but I’m missing something about how they are able to take two different parent plants, and come up with the same children every time.

I believe there are 12 gene pairs in peppers.  Shouldn’t there be more variation due to the various ways those 12 genes can be randomly combined?

If I take a Jalapeño and a Bell Pepper, and cross them 10 different times, won’t I come up with 10 slightly different peppers with various combinations of the parent’s traits?
 
If you crossed a Jalapeño with a Bell, the result wouldn't be a hybrid, as both parents belong to the same species: Capsicum annuum.
 
The result would indeed be a hybrid. It does not need to be an interspecies cross to be a hybrid.
The combinations are not random. They are a product of the dominant genes expressing over the recessive genes. They get the same thing every time because it works out like a math problem. the equation always give the same answer.
Generally to get a real true F1 hybrid you would need fully 2 fully distinct and uniform homogenous lines(usually lines that have breed past the 8th filial generation and are uniform or even uniform landrace strains) then the combination will appear as a fully uniform F1.
Things get more complicated with top crosses and poly hybrids. thats when you will start to see 2 or more distinct phenotypes expressing in the f1 generation.
 
 
The dominant genes that are expressed will always be the same with the F1 seeds as long as the parents were stable varieties. The recessive genes will be all scrambled like you're thinking, but won't show up until F2. 
 
I snagged a couple quick and basic examples that help to explain why the genes combine the way they do every time.
 
Here is for one single gene in a pair
IMG_20180219_195031366_HDR.jpg

 
 
Here is a breakdown for 2 genes
IMG_20180219_195043800_HDR.jpg

 
You can see how it gets exponentially more complicated as you start to figure for more genes and eventually all known genes simultaneously. 
The dominant gene always expresses over the recessive gene in the first combination. In successive generations the genes are recombined into new outcomes giving many different expressions.
Also keep in mind that this is just a basic explanation of genetic inheritance. There are many other, far more complicated factors, that come into play with inheritance and expression.
And that this does not explain the statistical possibilities of each combination of the different possible phenotype expressions. It is not just 1 in 4 or  3 in 8 because they are not actually created/combined equally in the same numbers, there are other factors at work. I'm only just beginning to scratch the surface of the statistical analysis of dna based genetic inheritance. Makes my head hurt trying to follow along with some of it, so i'm not gonna be any good at explaining that part.
Generally in a commercial setting like syngenta for example they use a database that has the genes of each specific plant mapped out and then they run algorithms  that combine all possible combinations and use that list to help select the parents for various crosses. Makes it way easier to get a consistent product with the traits they want.
 
 
There is also another possibility. I read a really great article about it in the 2018 Wild Garden Seed catalog. It was written by Frank Morton.
Here you can check it out. Its right there in the prologue but the rest of the article is definitely worth reading.
 
Thanks. I think Im beginning to see.

I was confused because I knew at least a few of the traits that are typically advertised must be recessive (just based on the laws of probability). But, if you have two specially cultivated parent lines with similar recessive genes where necessary, and only a handful of carefully selected recessive/dominant genes (carefully split between the parents), you can maintain the necessary recessive traits while still sprinkling in enough other recessive traits to throw succeeding generations into chaos as long as one parent has an off-setting dominant trait to stabilize the f1 generation.
 
From what I understand about genetics, self-pollinating (or pollinating to others of the same strain) and selecting over many generations will produce a highly inbred line that is very consistent with little-to-no genetic variability.

Having created such a line, the breeder will know exactly what genes he is working with. Crossing two distinct lines that have been bred and selected this way will produce uniformly predictable results in the F1 generation.
 
So how can a seed producer make sure that ALL seeds are the desired F1 crosses and not from self pollination by the mother plant? Are they manually removing the male parts of the flower of the mother plant?
 
MarcV said:
So how can a seed producer make sure that ALL seeds are the desired F1 crosses and not from self pollination by the mother plant? Are they manually removing the male parts of the flower of the mother plant?
 
As a secondary question to above - I keep reading about dominant and recessive gene, is it from the male or female part of the flower? Or can it be controlled by by pollinating the male/female part of the flower? What I mean is, I have a prolific fruiting plant, let's say BHUT JOLOKIA BLACK, that I want to have as the dominant gene and cross it with TRINIDAD SCORPION CHOCOLATE to infuse the better production? So, is it pollen (Male) from the Bhut to the pistil (Female) of the Trinidad or Trinidad pollen to the pistil of the Bhut? Or does it matter?

TIA Dane.....Your insightful knowledge greatly appreciated by forum members!
 
MarcV said:
So how can a seed producer make sure that ALL seeds are the desired F1 crosses and not from self pollination by the mother plant? Are they manually removing the male parts of the flower of the mother plant?
This is accomplished in a number of ways, some more successfully than others. One way like u mentioned is emasculation of the flower. The removal of the male parts of the flower on the chosen female variety before they become mature. This can be very labor intensive.
Another common way would be through male sterility. They use female breeding stock that has a male sterility trait. This way they avoid the extra labor costs of emasculation and hand pollination. But there is a trade off. Now you need to find or create desirable breeding material that has the sterility Wich can be expensive and time consuming or limiting if your trying to use the same one for multiple lines.
 
The_NorthEast_ChileMan said:
 
As a secondary question to above - I keep reading about dominant and recessive gene, is it from the male or female part of the flower? Or can it be controlled by by pollinating the male/female part of the flower? What I mean is, I have a prolific fruiting plant, let's say BHUT JOLOKIA BLACK, that I want to have as the dominant gene and cross it with TRINIDAD SCORPION CHOCOLATE to infuse the better production? So, is it pollen (Male) from the Bhut to the pistil (Female) of the Trinidad or Trinidad pollen to the pistil of the Bhut? Or does it matter?

TIA Dale.....Your insightful knowledge greatly appreciated by forum members!
It's not really from either side but from both sides. What I mean is that both the female and the male have recessive and dominant genes. It is the act of combining that causes a shuffling or mixing and certain traits to be expressed over others.
In the example you created with the black bhut and chocolate scorpion hybrid, if you want the offspring to be a little more like the black bhut you may want to make it the mother.
This is where it gets a little more complicated. Until now I have been discussing only one type of inheritance. There are 2 types of inheritance that occur during sexual reproduction. The first that I talked about is one for nuclear genomes (nDNA) that combine parts of the mother and the father. The other is mitochondrial dna (mtDNA) this dna will come directly from the mother only. This will make the offspring carry more dna from the mother than the father.
However this doesn't mean the offspring will be dominant for the mothers genes. It will still depend on which genes are dominant over the others.
 
The_NorthEast_ChileMan said:
 
As a secondary question to above - I keep reading about dominant and recessive gene, is it from the male or female part of the flower? Or can it be controlled by by pollinating the male/female part of the flower? What I mean is, I have a prolific fruiting plant, let's say BHUT JOLOKIA BLACK, that I want to have as the dominant gene and cross it with TRINIDAD SCORPION CHOCOLATE to infuse the better production? So, is it pollen (Male) from the Bhut to the pistil (Female) of the Trinidad or Trinidad pollen to the pistil of the Bhut? Or does it matter?
 
 

To elaborate a little on Dane's response, for those traits controlled by the nDNA, you can't change the relationship regarding which gene is dominant, and which gene is recessive.  Whenever the recessive trait is the desirable trait, the game is to get both pairs of genes to carry the recessive gene.  If either or both genes carry the dominant gene, the plant will exhibit the dominant trait.
 
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