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Hudsonville, Michigan (michiganpumpkins@sbcglobal.net)

If someone was focusing on creating a seed of Lloyd 935-type or 567.5 Mombert-type prominence (consistent offspring), how many generations of selfing or back crossing would it take to achieve and reinforce homozygosity? I suppose there would be a point after which you've gone 'too far' and any genetic flaws in the seed may become expressed and reinforced. How much is enough and how much is too much?
Frank

1/9/2004 10:56:58 PM

Appalachian Mtns.

I would think that's an unknown at this point Frank.

1/9/2004 11:15:15 PM

Omaha, NE (N41-15-42 )

I like the question. That has crossed my mind since AGs are so diverse. I hope others will chime in.

1/9/2004 11:36:15 PM

Deer Park WA

In my opinion it takes a minimum of three consecutive selfings to throw consistant offspring. Sibbing takes longer as the available gene pool is wider. There is another way that may be faster, but I want to test my theory one more season before offering an opinion.

1/10/2004 1:54:54 AM

Appalachian Mtns.

Check out the Willemse seed, he's up to 5 generations of selfing, and the seed is still producing well.

1/10/2004 2:39:21 AM

Ctpumpkin@optonline.net

Cool question.

If you're a member of AGGC go there. Choose the "Other" menu. Look at the dropdown box for "Helmet Laemmle" by David Garrell. I think this man's story is facinating. He grew in vitual isolation, making selfs for many consecutive years. His efforts have had statling influence on the seeds we grow now.

But I have absolutely no idea how many generations are needed before we see a purity level that fosters true "hybrid vigor', if indeed that can even be accurately determined.

Steve

1/10/2004 8:06:08 AM

Greencastle, PA

The 609 Laemmle was the pollinator of the 567.5 Mombert, that's a very big influence on the seeds we grow now.
Tom

1/10/2004 10:51:40 AM

Hudsonville, Michigan (michiganpumpkins@sbcglobal.net)

I pose the question because it seems most growers are making great crosses these days in an effort to get that extra vigor (whether or not it's true "hybrid vigor" is another matter...) But far fewer seem to be isolating/selfing traits for multiple generations. Without established isolated gene pools we diminish the possibility/opportunity to create this vigor in future years. I'm sure some are doing it, like Willemse mentioned earlier. But it's already getting harder to find a seed with no Lloyd, Bobier, Mombert or Calai in it.) Just food for thought. Perhaps there are more growers out there than I realize doing this already....the day the AGGC opens back up to new members, I'm there looking it up! I, for one, think we need to look beyond just this year or the next when planning what seeds to grow...
Frank

1/10/2004 3:44:36 PM

Colorado Hail, CO. Elev. 5,900 FT

Frank and all...
This is the question I hoped someone would start to wonder! With so many similar Calai/ Bobier crosses, I've been wondering the same thing, what chance of finding other genetic lines are there going to be down the road? Both of those genetics work so well since they have all 4 of the main isolated genes [ Dill / Waterman / Llyod / Laemmle ] as the factors which may be producing a hybrid vigor characteristic.

Gads reflects my same thoughts about selfing and sibbing crosses, and I would agree a 3 generation isolation should be the decent amount of time to then breed into another isolated genetic. True, this is not proven, but most of the current evidence does point to this hypothesis. I might throw in the possibility of speeding things up by breeding seed grown plants back with their mother the next year by means of propagation. Gads... is that what your trying to be hush hush about? LOL..

{continued in next post...}


"The clone madman" Marc Sawtelle

1/10/2004 8:48:56 PM

Colorado Hail, CO. Elev. 5,900 FT

I do not think a genetic can end up expressing genetic depression, unless it is inbred with less desirable plants which the dominant genes favor those less desirable traits. As long as the grower breeds the plants which are the best amoung all plants grown, there should not be any adverse results. This is how many growers get plants to breed true for a specific trait... they breed only the plants they like, and do not breed the ones which are lame.

So what is the solution folks? I am involved in my own project of creating a genetic, differing from todays genetic seed crosses. As mentioned, it is almost impossible to find seeds which are not tied somehow into todays gene pool... best one can do is find a viable seed from as far back as possible and self it for years/ then perhaps cross it into a current genetic... this is my muligenerational back crossing idea which I hope like hell pays off. I am currently trying to dig up what i can to pull this plan off...

I'd like to know everyones else's plans, or what others think is the best course of action for future genetics...

"I'm all ears!"

"The clone madman" Marc Sawtelle

1/10/2004 8:49:56 PM

Streator ,Illinois

Question Mark to the above statements-- if the pumpkin showed more traits from the fathers side would it be wise to breed back to the father then the mother.
(new at this genetic thinking )
Gene

1/11/2004 7:58:49 AM

Ontario, Canada.

Marc, The Willemse seed stock as kyle stated above goes all the way back as a selfed fruit line to the 674.5 Waterman 1990. Kyle and I have talked of this before. The 706-99 & 834.8-01 are about as pure as anything on the AGGC. I believe that they could be crossed with any number of new strains and might produce a vigorous cross. The question is which ones? It has been tried a few times however. The 900.5 Lyons 1994* is a product of the 706.5 mother fruit the 724-93 after 3 generations of selfing. Glen Cheam grew the 687.5-01* which is the 706.5 Willemse 1999 X 846.0 Calai 1999. I don't know if it was ever grown, the AGGC does not list any progeny for the Cheam fruit. Although the 687.5 was a squash, I would be willing to guess that there might be a possibilty of large progeny from those seeds. 710-00 is another example of the Willemse selfed fruit.

1/11/2004 9:19:16 AM

Long Island,New York

"I'd like to know everyone else's plans.......(for the super genetic).....LOL...Im sure you would Marc....IM SURE YOU WOULD....hee-heee......G

1/11/2004 9:20:49 AM

Western NY

as a few of you know, you run into two main problems when planning genetics. one is that what looks good on paper may not always be growing the best pumpkin, and the second part is actually getting those seeds planted to see what will happen. i'll give a few of my own examples - my 427, 315, 193, and 351 are all along the unique cross/hybrid vigor lines of thinking. of these four seeds, only the 427 and 193 have been given somewhat of a chance. each has grown a nice sized fruit, but has also had questionable results with other plants. the 315 has only been tried out once and did very well for the situation, i believe. the 351 (for those of you looking to cross different inbred lines - this is the one) has never been tried. it got to the point last year that i decided to only grow "top" seeds, and a few of my own and quit playing with the unique crosses. not sure if i'll do that again this year or not.

1/11/2004 1:07:13 PM

Utah

I don't think people are making crosses because of hybrid vigor... they are making crosses because they like certain charateristics in each of the two seeds... and they are hoping the best charateristics of each will emerge in the future. I don't believe there is any hybrid vigor in AG's the way we plant and cross them.

1/12/2004 9:53:17 AM

Pumpkintown, SC

This thread is right in line with my thinking and planning. I grow between 15-20 AGs with approximately 95% of them being old stock. My biggest hurdle each year is encouraging growers to blow the dust off their old seeds to grow or trade them for more current seeds before they're rendered un-viable.
I have found that most of the old seeds are possessed by most of the long time growers. The problem is that these long time growers seem to "get" and grow more of the current hot seeds and won't give/trade away their old stock to those of us who don't have "the name" in the sport, who are willing to devote multiple seasons to '90-'95 seeds. Thank you however, to those who do recognize this and help in this matter, BF

1/14/2004 5:53:32 PM