Breeding non-bitter cucurbita pepo nest egg gourd, johnny gourd, coyote gourd

[markwkidd]

Professor Porcupine gave some practical advice a month or two ago about the wild vines. And in fact, I did take a taste of the first fruit from every wild plant. I do recall that there was maybe a vine without fruit. Or I made a mistake.

What I’m getting at is that I discovered a nonbitter plant in the wild egg gourd area when I injured my knee and accidentally stepped on one of its fruits.

The very frustrating thing is that I have been manually crossing this vine with domestic varieties. And so while I would like to have a pure, self-pollinated fruit, at this late stage in the season there is no time to do that outdoors.

Therefore I have tried to get half of the vine to form new roots. Two weeks later I cut it in half. And today because of the forecast frost, I brought the two pieces indoors, one half that includes the original roots, and one half that includes whatever roots may have formed after two weeks with the vine buried.

I would really like to self pollinate this one, and I’m going to be quite frustrated if today’s move indoors isn’t enough to keep it alive and producing fruit.

After this discovery, I did taste one fruit from each of the remaining wild vines to see if any of those were non-bitter. They were not. This somewhat significantly reduced my supply of manually cross pollinated egg guard fruit, but I don’t regret doing it. I needed to understand what was going on. I could swear that there are two different levels of bitterness from different plants I tasted. Both far too bitter to enjoy, but one that was significantly more bitter than the other. Food for thought.

[VeggieSavage (Professor Porcupine)]

Interesting, so an edible Egg shaped pepo squash variety already exists!? Wow, doesn’t that just help speedrun your breeding efforts ha. Interestingly seeds are from Turkey? So maybe they were introduced a long time ago & had selection pressure for the egg shape? IDK how closley related they are, we probably need to see the fully mature fruit but it does look somewhat close.

@markwkidd

What I’m getting at is that I discovered a nonbitter plant in the wild egg gourd area when I injured my knee and accidentally stepped on one of its fruits.

Interesting! I’m so glad you found non bitter fruit this early! Was the entire fruit non-bitter? What about the seed strings? I’ve noticed even some grocery store maxima squash have bitter seed strings but non-bitter flesh. Since nobody I know licks each seed to taste the seed strings, I’ve found out that the Bitter-Strings trait translates into flowers with bitter center parts. Did you notice any bitterness in the flowers or leaves?

@markwkidd

I would really like to self pollinate this one, and I’m going to be quite frustrated if today’s move indoors isn’t enough to keep it alive and producing fruit.

It probably will have enough energy to finish ripening the fruits already on the vine (It can even do that off the vine, if fruits are somewhat mature enough). If the plant flowers, I’d recommend you save & freeze the pollen at the very least before the plant has a chance to die. That way even if the plant doesn’t make any more seeds, you can use the frozen pollen to pollinate next years crops!

@markwkidd

I could swear that there are two different levels of bitterness from different plants I tasted. Both far too bitter to enjoy, but one that was significantly more better than the other. Food for thought.

That’s a positive! I remember the loss of bitterness was a chance mutation, at first it was the edible seeds that were selected, then followed the flesh. Perhaps something similar is going on again. I wonder, is it purely genetic or is the enviroment/growing conditions affecting the way the same bitterness gene gets expressed? That’s not a thing is it?

[markwkidd]

These are my selections from the first and second generation crosses with Alpha. Some are back crosses and some are new crosses. Probably too many crosses for me to keep up with next year. The seeds in all of these fruit are related to one another. It is a grex in the classical sense of the term.

This photo shows a new egg gourd acquisition next to the two varieties I’ve used for the initial crosses: my ‘irregular’ shaped patty pans and the Desi squash.

I have a more morphologically consistent pattypan variety that I don’t think runs as true to the ovifera subspecies type. The large patty pan squashes in the wider angle photo are from this less intriguing pattypan lineage.

Edit: there is some discoloration on certain fruits where I let them get a bit frosty. They are normally the same solid white as their siblings.

[VeggieSavage (Professor Porcupine)]

@markwkidd

Edit: there is some discoloration on certain fruits where I let them get a bit frosty. They are normally the same solid white as their siblings.

Ah so that’s what happens to squash fruits during frost, good to know. Doesn’t it damage their storabiltiy tho?

Please do let use know how each fruit tasted, like what you found or noticed. Especially the bitter tastes like the Bitter seed-strings, Bitter flesh, Bitter seeds, bitter skin, ect.

[markwkidd]

I think it’s possible that bitterness in the flesh decreases over months in storage. Not enough to disappear completely but possibly enough to be relevant to understanding the domestication process.

Edit: I think this would also be very important to remember when using the taste of cucurbitacin as an indicator of toxicity. I think that this phenomenon would make it more important to taste unfamiliar Cucurbita fruit when raw, because a weaker bitter flavor is more likely to be hidden by cooking and seasoning.

I also believe it’s possible that there at least two distinct levels of bitterness among C. pepo fruits I have tasted. If this is true, I wonder if it is something like the difference between having one bitterness allele versus two in one of the bitterness genetic loci. As opposed something like soil and environment or stress response.

I hope my small grow out this year will allow me to continue learning, but it’s almost as important to me to catch up on my writing in order to consolidate what I’ve already been learning.

[VeggieSavage (Professor Porcupine)]

@markwkidd

I think it’s possible that bitterness in the flesh decreases over months in storage.

Interesting, and this isn’t technically part of the ripening process or is it just curing?
It wouldn’t be possible for a squash fruit to taste bitter immature and not-bitter when fully ripe would it?

@markwkidd

unfamiliar Cucurbita fruit when raw, because a weaker bitter flavor is more likely to be hidden by cooking and seasoning.

oh, good point. I think this is the case with some Cucurbita ficifolia being eaten by locals where it grows despite some hints of bitter flavor.

@markwkidd

I also believe it’s possible that there at least two distinct levels of bitterness among C. pepo fruits I have tasted.

Does it differ by which Subspecies? Both subsp. texana & subsp. pepo can be just as bitter right?

[markwkidd]

I’m very keen to clarify and otherwise improve my writing about this project, the expression of bitterness, etc. Let me see if I can get a little closer to clearly describing what I am observing and thinking.

Taxonomy

I am currently interested in the Cucurbita pepo subspecies with a native range in North America extending as far east as Kentucky. Often this is denoted as subspecies ovifera but I’ve seen it described as texana.

Some authorities classify the white egg gourds of Arkansas and Kentucky as ovifera whereas the Tennessee spinning gourd as texana. The ambiguity is why I specify small, non-ribbed fruit variously referred to as ‘egg gourd’, ‘johnny gourd’, or ‘coyote gourd’ in Kentucky. This fruit resembles fruit found in archaeological sites and in its wild state has been considered a food as well as a container or craft material (fishing nets, etc).

I’m using traits including seed and fruit morphology (as opposed to genetic testing, wouldn’t that be nice to have) to try to work with lines that putatively have a low amount of DNA from the other C. pepo subspecies.

Bitterness levels

I believe that the uncrossed wild egg gourds I have grown have a higher bitterness level than the F1 crosses between patty pan and wild egg gourd. The F1s are very bitter and completely unpalatable. But there are some wild egg gourd fruits that subjectively seem much more bitter than the F1s.

I am working from a genetic model of Cucurbita bitterness that involves three different genetic loci. This model asserts that there needs to be a bitter allele in each of the genetic loci, and that the bitterness genes across all loci are dominant.

I hypothesize that the reduced level of bitterness in my F1 crosses comes from having nonbitter alleles in one or more of these genetic loci.

Bitterness of fruit at various points in time

My impression is that immature fruit are very bitter by the time of fertilization.

I haven’t tasted as many fruit before maturity but my model for this would be that the bitterness level in the fruit may vary some as it matures, but it is essentially “full bitterness, full deterrent for being eaten” all the way from unfertilized fruit to when the vine dies at the end of the season.

What I have tasted in my saved F1 crosses is a decrease in flesh bitterness by the end of the eighth month of storage. I should note that I don’t keep any wild type egg gourds with the greater bitterness over the winter.

I should also note that at least one of my wild egg gourd lines has some non-bitter alleles in circulation. This means that some of the wild ones from that genetic lineage will have reduced or no bitterness in some fruit just like the F1 crosses from 2024.

[VeggieSavage (Professor Porcupine)]

@markwkidd

Often this is denoted as subspecies ovifera but I’ve seen it described as texana.

Aren’t they both the same subspecies?

@markwkidd

I hypothesize that the reduced level of bitterness in my F1 crosses comes from having nonbitter alleles in one or more of these genetic loci.

Perhaps that makes sense.

@markwkidd

My impression is that immature fruit are very bitter by the time of fertilization.

Majority of plants work like this to deter herbivores eating fruit when seeds aren’t ready.
However I thought Zucchinni, Cucumbers were different???
However weirdly enough Eggplants are eaten immature but I don’t understand why Fully Ripe Seed Mature Eggplants aren’t also edible.

@markwkidd

This means that some of the wild ones from that genetic lineage will have reduced or no bitterness in some fruit just like the F1 crosses from 2024.

Ooh, this is good! I still wonder why aren’t zucchinni bitter when unripe & fully ripe? The bitterness has been bred out excepet for Kaboacha Squash that can still have some bitter seed strings.
I wonder if the curing time is simply having the squash dry up a bit more & thus less water means less bitterness? It’s not possible for the fully ripe fruit to be bitter but the unripe fruit to be not bitter right? It’s either bitter at both stages or not bitter at either?

[ThomasPicard]

Thank you Mark for that incredible topic and Prof Porcupine for your inputs into that mind boggling research. I will refer to it as the main topic about bitterness in Cucurbits to friends.

Then, looking into your last synthesis Mark (thank you! Awesome!) I went to that simple question… WHY? but WHY Mark is doing that.

So I had to look into the entire topic to get to your goal, which is underlined in your first post:

@Seeds

My goal==

I am interested in creating as diverse of a grex of edible squashes as possible from the Ozark/Atlantic lineage. As a secondary goal, I am interested in whether there are desirable traits that can be added from genetically related feral and wild-type squashes.

Ok that’s clearer now. Then I would have expected you to set the emergence of known feral/wild related qualities into your grex as the main interest, of which I could haveimagined any thing from cold to heat hardiness, or specific bitterness in plant (but not fruit) that would repel animals.
So it seems like you had good intuition of things of the sort but no clear prior knowledge, right? I would kind of like it too, and would think it’s… Brave!

[markwkidd]

Thank you for your encouragement and the clarifying questions you provide.

I would like to start a new thread for this project where I can consolidate what I have learned and abbreviate some of the topics that I haven’t pursued. For now my untidy posts here will remain the primary record

My goals have shifted during the last couple of years in ways that I may not always articulate at the time. For one thing, I am now quite focused on the nest egg gourd. The egg gourd is the wild Cucurbita ancestor that has been collected closest to where I live and has significance to understanding of the agriculture and economies of the native people who farmed in my area before me.

Early, more diverse concept

I started by gathering interesting “gourd” type C. pepo fruits from other growers in my area. They are used decoratively. Often I found by tasting them that these C. pepo gourds were non-bitter. I had some very weird looking fruits in my potential gene pool.

By the time I needed to start planting squash vines, I realized that I wanted to try to incorporate the two kinds of free-growing C. pepo that could be found in my region: the nest egg gourd and the Tennessee spinning gourd. And chances were that would involve introducing bitterness genes to the project.

Joseph Lofthouse rightly pointed out that if I introduced bitterness to my population, it would be a significant effort to breed that back out. Which is absolutely true.

New genetic foundation: Northeasternmost free growing C. pepo

Having received that advice and others, I sort of inverted the breeding goal of the project and committed to learning what I could learn from choosing to include bitter genes in order to be able to work directly with the most local genes.

Since then, my goal has been to start with seeds collected from the northeasternmost free-growing egg gourds I can access from North America, and through backcrossing with closely-related varieties, arrive at a population of non-bitter egg gourds with genetics as close to the free growing types as possible.

These wild types aren’t necessarily the most resistant to all pathogens here but they reliably produce fruit, and self-seed in the right microclimate.

Current seed sources and the loss of the spontaneous non bitter egg gourd

I currently have seeds from three different free-growing populations in Missouri which I’ve received by the people who foraged them. I also have seeds from one commercial source. At least one of these seed sources includes spontaneous non-bitter egg gourds, but I accidentally discovered that last year after I destroyed the vine. That would have been so great to isolate and save seeds from

Composition of current crosses

Last year I did grow out some of the wild seed sources, but all of my crosses descend from “alpha”, one cross between nest egg gourd and patty pan in 2023.

I wish I could grow out more wild populations in isolation from each other. For one thing I think it’s very likely that I have some other spontaneous nonbitter seeds in one of my four groups of wild types.

[markwkidd]

@VeggieSavage

Aren’t they both the same subspecies?

My observations pertain to two general scenarios:

• understanding the subspecies or genetic type of a squash being described in an academic paper
• understanding this subspecies or genetic type of a squash being offered for trade or sale

In those situations I have found widespread inconsistencies about the C. pepo populations found in North America.

It’s not unusual to have classification and consistencies like this, Cucurbita pepo taxonomy is a bit more mixed up than average due to changes in time and the uncertainties of folks terminology.

I suggest checking and double checking anything that is assigned to subspecies or clades named fraterna, ozarka, and ovifera. Look at photos and read morphology descriptions to make sure you understand on what basis it was assigned to that subspecies.

Researchers and seed vendors alike sometimes just repeat whatever they were told when they received a seed. And at earlier points in history there were different understandings of the taxonomy of C. pepo, or what was considered wild versus a possible feral garden escapee.

[VeggieSavage (Professor Porcupine)]

@markwkidd

They are used decoratively. Often I found by tasting them that these C. pepo gourds were non-bitter.

Seroisly?!?! You found non-bitter ornamental types? That’s something I wanted to breed for, the cool shapes look fun, I wonder the unique summer squash shapes that can be generated from their genetics!

What do the non-bitter ornamental types taste like? Sweet or sweetless? Spicy or other flavors?

@markwkidd

For one thing I think it’s very likely that I have some other spontaneous nonbitter seeds in one of my four groups of wild types.

Wait so one of them only has non bitter seeds but still have have bitter flesh?

@markwkidd

In those situations I have found widespread inconsistencies about the C. pepo populations found in North America.

Well it also doesn’t make it easy to sort when all of the subspecies are crossing with feral populations as well.

Correct me if I’m wrong but isn’t this the main difference between both? (Of course hybrids are all over)

@markwkidd

I suggest checking and double checking anything that is assigned to subspecies or clades named fraterna, ozarka, and ovifera.

Good idea altho Subspecies Fraterna is the other subspecies that turned into subspecies pepo right? They used to be 2 ancient species (Cucurbita fraterna x Cucurbita texana), they have been thoroughly introgressed into modernday Cucurbita pepo and thus have blurred the lines between subspecies. How do we know the wild suspecies of Cucurbita pepo are truly wild or simply feral semi-wild escapes of Native American Landraces?
What is considered wild now?

From my notes “C. pepo was likely created by an ancient Hybridization Event between C. texana and C. fraterna, which were originally 2 seperate species. Truly wild forms of C. pepo subsp. pepo weren’t found, only subsp. texana & subsp. fraterna were found in the wild. Unlike most wild Cucurbita, some specimens of C. fraterna fruits have been found without bitter fruit. 2 distinct domestication events, one in mexico & one in Eastern U.S.”.

Does this make sense?

[markwkidd]

@VeggieSavage

Correct me if I’m wrong but isn’t this the main difference between both? (Of course hybrids are all over)

I don’t think there is a consensus yet about the number of subspecies and their boundaries.

Have you seen Teppner’s taxonomic work? I believe his treatment of texana and ozarka as being within ovifera is based on modern genetic investigation.

Cucurbita pepo L. (Garden-Cucurbit)

• C. pepo subsp. fraterna (L. H. BAILEY) LIRA, ANDRES & NEE
• C. pepo subsp. ovifera (L.) DECKER
  • C. pepo subsp. ovifera var texana
  • C. pepo subsp. ovifera var ozarka
• C. pepo subsp. gumala TEPPNER
• C. pepo subsp. pepo

The paper where Teppner proposes Gumala as a subspecies may be particularly interesting to you. I’m having trouble finding it though! He believes he may have found the closest descendent of the Mexican wild C. pepo lineage.

[VeggieSavage (Professor Porcupine)]

@markwkidd

I don’t think there is a consensus yet about the number of subspecies and their boundaries.

Hahaha! Not with our landrace efforts, crossing everything altogether even further .
We are gonna give taxonomist some serious headaches

Just wait till we make a 5 species Cucurbita landrace, with all species fully hybridized & introgressed! Might we make a new species ?

Very interesting, I’ve never heard of subsp. gumala.
I wonder if they contain some Cucurbita lundelliana & Cucurbita okeechobeensis genetics that have introgressed into Cucurbita pepo gene pools some long time ago during domestication. Just look at this phylogenic tree and how Closely related C. lundelliana is to Cucurbita pepo. Might even be the “Cucurbita angyrosperma is not quite separate species from Cucurbita moschata” situation all over here again.

I found this about supsp. gumala “The plants have depressed-globose pepos 13–20 cm in diameter with extremely thick rind, ripening orange-yellow, and with orange flesh.”

Cucurbita pepo - FNA

[markwkidd]

Could this be an example of the native environment of Cucurbita pepo subsp. ovifera? Or if not, could it be an example of a environment where the earliest domesticated C. pepo were grown?

I was passing somewhat near this site so I took the opportunity to look around. It felt a bit like a pilgrimage at this point, although I should come back when I have more than a few minutes to look around. I think this will take about two hours to reach from where I live. As the crow flies it’s probably 60-70 miles from here.

I had a chance to visit the coordinates of the most recent potential wild Cucurbita pepo population documented in Eastern Kentucky, around the end of the 1980s or 1990ish. Some resources about the history and domestication of Cucurbita pepo refer to archeological sites or C. pepo populations in Eastern Kentucky – this is the area being described.

My understanding is that in Western Kentucky, a few hundred miles west of here, C. pepo gourds are not too uncommon. I have not had the opportunity to forage there myself. I have had contact with several people who have found them growing wild in Missouri where they seem to be even more common.

In Eastern Kentucky where I live, I have never come across any potentially wild C. pepo populations. But there are archaeological remains of small C. pepo fruit from thousands of years ago from relatively close by.

In Eastern Kentucky, as recently as the late 1980s or 1990, free growing C. pepo was collected in Powell County. This is an area with ancient native settlements with archaeological remains of small C. pepo subsp ovifera fruit, and we could speculate either that Powell County and Eastern Kentucky was once part of the wild range of C. pepo subsp ovifera, or that the 1990s free growing population was a relic of an ancient domesticated variety. Both could be true or something else.

Having visited the coordinates of the Powell County site, I agree with a notation from the time that it’s hard to imagine this having escaped from a garden. Today just like 40 years ago it’s very far from any settlement or agriculture.

I had a chance to talk to one of the people who found fruit at this site back then. They unfortunately haven’t been in a position to spot it recently but they encouraged me to look to see if any is still growing in the area.

Edit: I have added seeds from four of the 2024 crosses to the Serendipity Seed Swap! (US). I made more crosses than I can pursue myself. These seeds should have about 10-35% egg gourd DNA.