Re: Hybrid Vigor?
Mike;
I am with you 100% that the careful selection and reselection of exceptional
specimens, generation after generation, is the method to be able to breed for
increased size into a strain. When vegetable breeders plan to make a hybrid
vigorous genetic, they have a desired result in mind when they breed for
vigor. They select desired traits which they wish to combine to make a better
plant variety from plants with different characteristics from both to create a
specific trait. A tall corn breeder trying to create taller giant corn will
start off by selecting the plants which exhibit the best traits from his
initial seed stock. He will grow several generations of a favorite genetic
strain, breeding only the plants which exhibit the best genetics, and
discarding the plants that do not. He will grow that variety until that
genetic "breeds true", which may take several seasons before reaching that
point. Once that initial point is reached, and the grower has a true breeding
tall corn plant, throwing 3 foot ears of corn, exhibiting little disease
problems and good bug resistance {if those desired traits were already bred
in...LOL}, then perhaps the tall corn grower wishes improve the genetic. Lets
say, he is happy with the growth & size of the plant, but he thinks it would
be more cool to try to breed for 4 foot ears of corn rather than 3. The grower
would have to find another species of corn, one that may not have the growth
and size characteristics his genetic does, but might be famous for 4 foot ears
grown from that genetic. Assuming that the other variety has been bred to
produce true breeding plants as well, the only way to improve his species of
corn so it grows 4 foot ears as well as exhibits all it's good initial traits
is to cross both species. The offspring produce F1 Hybrids, combining the two
plants genes, which ever trait is dominate and which ever trait is recessive
will determine the characteristics and behavior of each seed. The grower then
has to start all over again, finding the plants which exhibit both desired
characteristic, breed only those plants, and slowly begin to isolate only the
plants that grow as desired. The plants that do not meet the required results
are not used, and the genetics that do, are bred for several generations once
again until only the plants growing 4 foot ears and growing 25 feet tall are
consistently showing to be the dominate genetic, and it's offspring are
breeding true, growing only those type of plants. The initial F1 hybrid plants
which didn't grow as desired eventually became extinct, as those undesired
traits were bred out of the species over time.
With pumpkins, nothing much differs from this practice. Growers have their
favorite traits, whether that be color, fruit thickness, fruit size, stem
length, leaf size,...whatever. The main thing all growers desire as the # 1
trait most important to them is fruit size. Since everyone is breeding for
size, why is it not possible to breed plants hoping to get a hybrid vigorous
genetic which exhibits larger fruit when 2 different types of genes are
combined? The hope is to make a cross and get plants that will be genetically
vigorous for increased fruit size. Unfortunately, it is much more complicated
sometimes than growers think, and proof would be the 845/723/846 seeds and
their offspring. There are many more seed crosses that exist which fail to
produce hybrid vigorous plants exhibiting larger fruits, than there are seed
crosses which actually do. Finding the genetics which have better chances to
combine and do that requires substantial research, or.... in some cases,
really, really, good luck...I mean REAL good luck...LOL!
My thinking on the "how to" part of creating vigorous crosses lies in the
belief of selfing genetics, researching possible parent crosses and selecting
the ones to grow based on how well they will cross with other genes, and
creating more isolated, stable, and predictable seed strains.
If there is one thing to be learned from pumpkin genetics, it would have to be
this: "pumpkin genetics are about as easy to comprehend as members of the
opposite sex are to comprehend."
Hope that explains my theory good enough, Mike... Not looking for an argument,
and not looking to write any more term papers...LOL! Would appreciate some
input on this subject Joe Atlis/ Tom or Nic, or anyone who has thought this
out for years and has or is in the process of getting grey hairs from dwelling
on...LOL!!!
'Madman' Marc
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