olivier75 wrote:
Taste is also taken into account, f1 does not mean without taste, and less and less.
Generally speaking, an F1 hybrid is a "combination" of traits that have been "assembled" from the pure lines used as parents. To take the example of my batavia (although I do not know any hybrid batavia), this would consist in having a parent A, very resistant to the rise in seeds, a parent B having a pleasant nutty flavor, a parent C forming beautiful apples and a parent D with red leaves.
All these characters were "concentrated" in these lines, then in both parents, by consanguinity ... They are "homozygous" - that is to say that in their descendants, it will inevitably be found. Inbreeding will lead to a sort of degeneration (corn production fields are easily recognized - we have small corn).
So by crossing all this, we will have a hybrid with all these characteristics every time.
And curiously enough, instead of regaining the initial vigor, we have heterosis effect, a bit as if the plants were "happy" that we had finally crossed them. The heterosis effect, also called "hybrid vigor". In short, 1 + 1 = 2,2 or 2,3 ... The 0,2 or 0,3 in addition, it is heterosis ... It is a "gift of nature".
This is what has boosted the development of hybrids.
This is a natural phenomenon, which we know in nature - "bastards" are often less puny than purebred dogs, which often have "congenital" defects.
But it depends on the species. In wheat, the hybrids did not break through. The heterosis did not justify the additional cost ...