Pepo x Argyrosperma (Mixta) "Lotto"

[Ferdzy]

Last fall I was trying to get people interested in an apparent cross between these two plants (originally Lebanese White Bush x Tennessee Sweet Potato). I did not have much luck but in trying to "sell" it to other people, I managed to "sell" it to myself, so we have planted a few seeds of it to see what happens. I planted 4 seeds, three of which came up (in two spots). These plants will be from the original cross either selfed (unlikely? or is it?) or crossed other semi-random zucchini (pepo). By semi-random, I mean one or more of 4 other zucchini planted last year. I may or may not be able to tell which one(s) once they start producing fruit.

Our hope is that these will ultimately become fairly typical zucchini of some kind, but with the bug and disease resistance of argyrosperma, as well as more heat and drought resistance than is typical of pepos.

I cannot see how they can  be anything other than a cross between the two plants listed above, given what else was in the garden when the cross would have occurred, and what they looked like, but it has been surprisingly fertile and easy to germinate for an interspecies cross. The shell of the squash from last year was extremely hard, the flesh was crisp even when cooked for a long time, and the flavour was bland and uninteresting but not bitter, which I gather has been a problem with these crosses. It was not good as a zucchini - the flavour was okay but large hard seeds started forming at a very early stage. We roasted and ate most of the seeds at the end of the season, and they were very tasty, as argyrosperma is known for. Given how tough the rest of it was, I was afraid they would be like little bricks, but in fact the skin of the seeds was surprisingly delicate.

Speaking of which, I believe the fruits we harvested contained about half their potential seeds. I don't think this was a fertility issue; squash in general did not seem well-fertilized last year. It was extremely cool overall, with a few good bursts of rain but long stretches of dry.

I'm naming this project "Lotto" because I think that's about the likelihood of anything really successful coming out of it, but hey! You never know.

So far they look larger than average, but have no sign of the silvery markings that are on all the other zucchini but one (Costato Romanesco). Here they are, on the right, next to Mutabile on the left:

[Ferdzy]

The first two fruits are starting to form on the two different plants; the third plant has only male flowers. Male flower production on all the cucurbits has been insane this year, with scarcely a female one to be seen. However they finally seem to be starting. The other fruit is equally pale, but looks like it will be rounder. It is not as far along as this one. I'm encouraged that it looks fairly zucchini-like at the moment. I guess we'll eat this one and see what we think, and not start leaving them to go to seed until later. A plan that makes me a little nervous, but really, there's loads of time.

[Chance]

Ferdzy,  thank you for updating us on this project.  At some point I would still like to participate.  I like costata a lot and also tatume.  Retaining at least somewhat of a vining habit would be good for resilience but bushiness is related to earliness right?  And even if you don’t have borers in your area you can select for thin vines like Joseph does with maximoss.  Looking forward to updates.

[Ferdzy]

The bad news is the squash pictured began to turn a little yellow and failed to get any larger, so we picked and ate it. However, there are two more coming along that are already bigger than that one ever got.

The more bad news is that even at that size, it was noticeably crisper in texture than a couple of other, regular pepo, zucchini I had picked at the same time, and extremely bland.

[Chance]

What’s amazing is the high fertility from early on.  It will be interesting to see if that continues for this generation.  With fertility you can theoretically select for flavor etc later.  I guess what I would attempt if I got seed is select for thin vines the next generation, then cross those to costata or tatume or some tasty vining pepo. 

[Ferdzy]

Chance, I think there is so much potential variability in these seeds that they could be grown out for years - especially at the rate of three at a time  - and some fairly different results would turn up each time.

I don't know where the pollen came from from this first, fairly typical, zucchini came from, but I'm guessing the second one was from Ronde de Nice since it looks like having a fairly similar shape. Both plants seem to be reverting to the skin pattern/colour of Lebanese White Bush. Looks like the one pictured is retaining a little of the argyrosperma "bottle" shape.

I took a photo of the first edible fruit I picked along with a selection of other zucchini picked at the same time to give some sense of scale. I picked it on the small side, as last year at that size they were already developing unpleasantly large and tough seeds. As you can see from the second picture, this year the seeds seem fine. Texture was much better on this properly developing fruit than on the first one, but flavour was just blaaaaaand. A little hard to say for sure, I tasted it raw then grated it up and cooked in vegetable patties so really only could assess it raw.

[Chance]

 I wonder if any of the seeds look similar to argyrosperma.  The long cooking time is probably not a character of pepo right?

[Ferdzy]

I couldn't tell you offhand whether they do or not. We only grew argyrosperma once, and decided we didn't like it much, so I am not that familiar with the fine details of it. I can say that the traits of the very hard skin, the flesh that stayed crunchy even when long cooked, and the seeds that developed extremely early were all things I have not seen in any pepo squash I'v grown.

I picked the "round" fruit today. It seems like it will be rather strange. The stem was so tough and hard to cut - actually, I think the other ones were too, so that's another difference from straight pepo. This is what makes argyrosperma so resistant to vine borers, I guess, but it looks like it will also make the fruits a little hard to pick.

Tomorrow or Monday I will cut it open and have a look at the round one - I'm calling it round, but it was starting to become an odd heart shape. I wonder if this one actually crossed with an acorn squash? They aren't that close and I was discounting them, but maybe I shouldn't.

[Ferdzy]

Okay, cut and ate the first fruit from the second plant. It gets rated as an instructive failure. Firstly, the seeds were more developed than I would want to see this early; the flavour was not just bland but there was also a slight aftertaste that took it from "meh" to "neh"; and the texture was noticeably crisp/tough especially the skin.

I suspect that the other parent of this was an acorn squash.

What was instructive though, was that it suggests one of the limitations I'm going to run into. I want the argyrosperma to bring resistance to vine-borers. That resistance comes through very tough stems. What I'm thinking now, is that if you get really good toughness in the stems, you are going to get toughness in the skin and flesh of the fruit too. A balancing point is going to have to be found.

Think I am going to pull this plant. It is one of the two that came up within a couple inches of each other, and right now it is crowding the other one into non-production. I'm clearly not going to want to save any seeds from this - I can already see (from the other productive plant) that there are better ones out there.