Re: Pumpkin Genes
Im attaching a couple of clips from the archives that bear repeating. One
is from Rick Noffke, the other from TerryLynn Sullivan, aka PumpkinWitch.
I know a number of good growers who are separating and tracking seeds from
specific lobes, but I'm not convinced even that will give us the specificity
we want and need to better understand how these genetics are working. Rick
is possibly the most knowledgeable person I've encountered on these subjects
and he says "each seed was the product of a different ovule and a different
pollen grain". My understanding is that each ovule represents one seed, and
not one whole segment. I hope that assumption is correct. If each pollen
grain is different genetically, and it takes a grain of pollen for each seed
(okay, Kathie, for each potential seed), then the variability really does
seem scary. Could at least the female genetics be consistent within each
lobe??
And TerryLynn says that even in plants that are pollinated by a single grain
of pollen there is variability. Oh dear.
This is definitely a hot topic that is getting more and more attention.
Beth
##
First Clip:
Its my understanding that each "ovule" is fertilized by an independant
pollen grain. Each pollen grain grows its own pollen tube and fertilizes
one ovule. Unless you control hand pollination well enough to only get
pollen from one male on a certain segment, all segments and all individual
seeds in each segement will be subject the genetic variability in the mother
and father.
This is where some of the strange things that are going on in AGS genetics
are occuring. You see great variability among seeds from one fruit. It is
easy to see the chances for such variability when each seed was the product
of a different ovule and a different pollen grain.
(Rick)
Second Clip:
Due to individual pollination of each section's seeds, the genetic
variation should be phenominal. But not as totally bewildering as it sounds.
Remember that since all the ova comes from the parent plant, you can, at
least be sure of those genes being contained somethere sithin the assorted
seeds. the variation comes from the ability to have a different pollen
parent for each segment's seeds.
While this increases the variation, since even with the same pollen
parent; each grain of pollen has a different make-up than any other. As a
result, yes, the seeds from each segment could still produce offspring that
varied quite a bit from the offspring produced by any other segment.
Many plants are polinated by only 1 grain of pollen. Yet there is
variation even among that seed. I beleive that the variation is more than
just between segment to segment, but the only way to discver this is by
"variation testing". We should have to take a pumpkin, carefully "deseed"
it, noting which seeds came from which section & then plant all the seeds in
specially marked plots. I would tend to want every seed planted, rather than
a representative sample. This in case variation was minor.
(PumpkinWitch)
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