Today I found a research group that saw that when you breed genetically variable squash and did interspecies pollination, most of the seeds were nonfertile. They saw the keyword, most, and thought hey, at least its not 0%. They through every trick at it including back crossing, outcrossing, and self/sibling crossing to power through the dismal fertility rates in the first dozen generations. They outlined a very confusing breeding protocol (Attached as an image if I did this right) they developed to create a tri-species hybrid that could readily pollinate and create fertile offspring with pepo, moschata, and maxima squash.
Their goal was to create a genetic bridge to be able to easily transfer disease resistance and environmental tolerance between the species. Unfortunately it doesn’t look like them or the company they developed these through sell any of the 11 strains they developed.
I would put forward that maybe someone should contact these researchers to see if the results might be shared. That’s the kind of thing I might take on in a month or two, even though it would maybe just be some emails I would like to be a bit more centered than I am right now.
I’ve got this paper prominently bookmarked so that I keep thinking about it.
Out of curiosity, what other papers and sources are you all reading from? I have a few I found interesting and could share. I’m largely trying to get a trait out of both pepo and moschata and into maxima.
I just went through and tried to find recent works for each of these authors. The only other works that they have published was them creating a lot of the ball summer squash I’m familiar with and several new pumpkin color patterns.
I went looking for each of the authors and where they work now. The first author still works at Hollar. The second now works as a farm manager and squash breeder for another seed company. The third author is now the president of Hollar. I’m betting they used these hybrid strains to create a lot of their new PMR and virus resistant pumpkin/squash strains. I also found a patent for a gene that gives powdery mildew resistance in one of the pepo varieties they used for breeding stock for the hybrids
If you’re interested I could point you in the direction of the second or third authors information that I found to contact them.
Attached is the only picture of one of these tri-species in the paper that had a zucchini bush habit, moschata coloration and stem, and maxima fruit shape. Genetics 25% pepo, 25% moschata, 50% maxima before 12 rounds of sibling inbreeding so who knows what it was after that.
I was working on the squash related parts of Wikipedia a few months back. Let me try to remember other references that might be useful. I looked at quite a few and they’re getting a bit blurry in retrospect when I know there is someone else interested it can help perk up my memory though!
Hmm, I haven’t though about the possibility of reintroduction of bitterness with my future crosses. I’ll have to figure out how to test for it earlier (like tasting the leaves I saw mentioned on this forum) so I can remove the bitter plants.
Here are two articles that I found interesting. One of these was an old article that was one of the first to bring the ZYMV resistance trait from pepo to moschata through traditional breeding. The other is a relatively new article about bringing the hull-less trait from pepo into moschata (what I want to do with maxima).
Funnily enough, the older article mentions how its easier to make the interspecies crosses using outbreed or genetically diverse samples instead of inbred varieties, so landrace stock should have a leg-up if someone wanted to work harder on this. From what I’m seeing, its only the first 2-4 generations that have some fertility issues that need a lot of nursing (which is probably why F2 and F3s are rare in nature, if only 0.2-1% of F1 seeds are fertile), but after that they rapidly recover to normal breeding rates. This is only what I’ve seen through pepo, moschata, and maxima research, I’ve seen others say crosses with arygyrosperma, ficifolia, and lundelliana have better chances.
Hi, all. This is your moschata/maxima squash steward, Debbie. I’d like to gauge interest in interspecies squash hybrids. If you have a moment, please comment here:
when I know there is someone else interested it can help perk up my memory though!