tetsukabuto F2?

[cletus]

This one sounds interesting, I will try it next year. A male sterile hybrid of maxima x moschata so you have to have a male pollinator for fruit set, I believe the Japanese use C. maxima to this end. I'm growing in borer territory so I will try a moschata pollinator. I think I read that tetsukabuto have few to no seed, a quality perhaps good for the market, but not landrace seed growers. Does anyone have experience with taking tetsukabuto to the F2 level, is it doable?

[Joseph Lofthouse]

Cletus: Hmmm. That's interesting to think about... Each year I have about 5% of my winter squash which fail to produce viable-looking embryos inside the seed coat. The squash I ate yesterday was like that: The seed coat formed normally, but the endosperm inside it was paper thin. I didn't think they would be viable. The squash was ok tasting, but not great so I tossed the whole lot of seed. The squash was plenty ripe. Sometimes the seed coat only semi-forms like the seed stopped growing when it was very immature. Sometimes there will only be a few normal looking seeds in a squash and lots of aborted seeds.

I have been growing mixta, pepo, moschata, maxima, and lagenaria side by side. After all, everybody knows that they are different species so they won't cross. Now I'm wondering if there might be some inter-species crossing going on? Gah!!! One more thing to pay attention to. I threw a squash away this fall that was growing in the mixta row because it was "wrong species". Hmmm. Wondering if that was a hybrid. I suppose that rather than throwing away the seeds from "mostly infertile" fruits that I aught to be giving them a special place in my garden just in case they are inter-species hybrids. And it might be prudent to pay closer attention to phenotypes.

[raymondo]

The guy who runs Real Seeds in the UK grew out a moschata/maxima cross and found it a challenge, especially the F2. See www.realseeds.co.uk/research.html for his description of things.

[Hristo]

F2 seed production was low, but not zero, so it's not a problem. Though if I wanted to breed good quality interspecific variety I would start with my own maxima x moschata cross because I find Tetsukabuto quite inferior quality. Of course that could be because of the local conditions and maybe Tetsukabuto is good at other places.

[cletus]

Joseph, it would be interesting to see at least. Such interspecies hybrids may reduce fertility barriers too much among your landraces and need to grow separately. Thanks Ray for the link to the work done at Real Seeds which sheds good light on this. Hristo, thats cool you got F2s from the tetsukabuto, what was the pollenizer? Bummer you didn't like tetsu's table qualities though, thats why you should send me those seeds ;]. Your experience may indeed be climate related. It seems the Japanese like their squash/pumpkins/kabochas with a sort of dry nutty character, more lending itself to a savory soup or tempura more than say a butternut. I've had "kabochas" from the store of the maxima type which are delectable. The maxima kabocha's flavor seems to have some crossover qualities with the moschata-type kabochas like kikuza and shishigatani which I've yet to taste but are described also as nutty and dry. That is why the tetsu types (several ones listed on KCB samen) sound interesting, borer resistance and vigor with a nutty flavor component. The kikuza and shishigatani are apparently very low vigor so I'd like to do some hybrid swarming with them, tetsukabuto, and seminole pumpkin. Some individuals of maxima and moschata initially cross very well to produce lots of tetsukabuto-type seeds, but this may not make it easier to get their genetics into a landrace. There are lots of moschata I want to taste and maybe put in the mix. I don't want to mess much with the borer susceptible maximas on their own, but it could be cool as part of a resistant hybrid or landrace with their table qualities and added genetic diversity. On the other hand it could be too much genetic diversity and not combine well into a landrace, especially initially. The post on Real Seeds indicates the propensity to disaster, ruining the taste of the parent types but also they came up with a new useful and tasty variety (species?).

[steev]

Having no opinion about the specific value of what you're doing, Cletus, I'm impressed by your vigor. You go, Dude!

[Joseph Lofthouse]

I've been growing the 5 species of squash side by side for 5 years. Always with lots of honey bees working the patch because of nearby apiaries. So far fertility hasn't been a major detrimental problem. It's like one fruit in 20 that shows low seed viability. Until today I haven't had a working hypothesis about why fertility might be low in some fruits.

This is the first year that Mixta has produced a fruit for me (only one fruit), but it has produced pollen every year. There were only a couple dozen viable looking seeds in this year's Mixta fruit. (Only two mixta plants flowered.) Pollinators within 10 feet were Maxima, Moschata, and Pepo.

Mathematically, if 5% of the fruits are low fertility due to being new inter-species hybrids, and they only produce 1/10th the seed of a normal fruit, then the low-fertility issue is self-limiting... As long as there are any high fertility plants at all in the patch, they will tend to swamp out the low-fertility plants due to producing ten times more seed. If the low-fertility fruit doesn't produce any viable seed then it is really self-limiting.

[cletus]

hahaha thank you Steev, we'll see where it takes me. Joseph, while not entirely related, your post reminded me of this article I read yesterday. They make the argument that ugliness is also self-limiting among some animals.
www.businessinsider.com/beauty-study-at-russian-fur-farm-2013-11

What you say makes total sense, and goes along with the post on Real Seeds. While cross pollination among species isn't much of a concern, I suspect it could be if greater fertility was developed among these hybrids, like that Winter Monster of Real Seeds. One that I'm going to work on at some point is naked-seeded borer-resistant type, whenever I have the large amount of space such experiments require.

[ilex]

Nov 14, 2013 23:39:58 GMT -5 cletus said:

... and shishigatani which I've yet to taste but are described also as nutty and dry. That is why the tetsu types (several ones listed on KCB samen) sound interesting, borer resistance and vigor with a nutty flavor component. The kikuza and shishigatani are apparently very low vigor ...

I've grown sishigatani, it has very good flavour, but as you say it's different. Quite fine grained, good flavour and very consistent. I don't think it's low vigor, I do think it requires a long season. I've got a cross with a local mostacha, and the F1's are very vigorous, will try in a month or so.

[steev]

In general, I very much like these small Japanese squash/pumpkins, although I've had meager success growing them; not their fault, I'm sure.

[Gianna]

I grew a lot of kabochas this year - mostly unknown seed from store-bought squashes. There was a great degree of variability and while they all looked like kabochas, the quality was too variable for my preference. Some were great, but too many lacked top-notch flavor.

I had been reading good things about tetsukabuto and found some reasonably priced seed mid season, and planted 6 seedlings out around Aug 1. We have a long season (It's been sunny and in the 80s this past week) so I thought I would give a few a try. Even late, I found the vines to be far more vigorous than the other kabocha types I grew. I have not yet tasted the fruits (they are still on the now-ratty looking vines) and then they need to cure. They certainly won't be as good as full-summer grown, but I'm looking forward to trying them. Maybe at Christmas.

I personally prefer the dry-nutty-sweet kabochas and hope the testsukabuto grown here in SoCal lives up to it's press.

[Hristo]

The pollenizer was Atlantic Giant. It was a few years ago, but AFAIR I did not used the seeds so I should still have them. But if you look for taste this cross is not the best one, to say the least.

[Deleted]

Hi, Hristo!
Do you know about the tries of Ron Rahe with Tetsukabuto and AGs?
www.bigpumpkins.com/Diary/DiaryViewOne.asp?eid=145513
This fruit weighed 14 lbs., but sibblings from 20 to 55 lbs., and all should have been F2 from Tetsukabuto x Atlantic Giant furthermore pollinated with C. maxima Atlantic Giant.
Hristo, please tell me: why do some of these fruits look like C. moschata `Shishigatani´ then?
Do you have an idea?

[Hristo]

Acorneti, no, I was not aware that he played with Tetsukabuto. I know he experimented with some crosses, like with x Rouge Vif D' Etampes, but was not aware for the Tetsukabuto's cross. I see there is no follow up though. Personally I saw no valuable traits in Tetsukabuto and did not continued with it.

I do not know it's parents so I can't comment much. I have seen AGs with reverse piriform shape so it could come from the AG too, but the heavy ribbing should come of one or Tetsukabuto's parents.

[oxbowfarm]

Nov 14, 2013 0:44:28 GMT -5 Joseph Lofthouse said:

Cletus: Hmmm. That's interesting to think about... Each year I have about 5% of my winter squash which fail to produce viable-looking embryos inside the seed coat. The squash I ate yesterday was like that: The seed coat formed normally, but the endosperm inside it was paper thin. I didn't think they would be viable. The squash was ok tasting, but not great so I tossed the whole lot of seed. The squash was plenty ripe. Sometimes the seed coat only semi-forms like the seed stopped growing when it was very immature. Sometimes there will only be a few normal looking seeds in a squash and lots of aborted seeds.

I have been growing mixta, pepo, moschata, maxima, and lagenaria side by side. After all, everybody knows that they are different species so they won't cross. Now I'm wondering if there might be some inter-species crossing going on? Gah!!! One more thing to pay attention to. I threw a squash away this fall that was growing in the mixta row because it was "wrong species". Hmmm. Wondering if that was a hybrid. I suppose that rather than throwing away the seeds from "mostly infertile" fruits that I aught to be giving them a special place in my garden just in case they are inter-species hybrids. And it might be prudent to pay closer attention to phenotypes.

I definitely think there is some interspecies fertilization effects that occur. In 2012 for example was the first year I grew Joseph's landrace butternut in with my own butternut grex. Joseph's squash was considerably earlier maturity and started actively flowering about a week earlier than mine. One plant flowered almost two weeks earlier and was the only moschata flower open at that time. I was disappointed that it wouldn't set the fruit, sad to lose the super earlybird genetics. But low and behold it did set on! I'm pretty sure that it was because of all the pepo pollen the bees were carrying around from the acorn squash that was not too far away. When I cut that fruit open, there was an empty cavity, no sign of seeds at all. My theory is that the pepo pollen was enough to initiate fruiting but the embryos aborted pretty quickly thereafter.

I also think that what you get a lot of times with aborted fruits is something like this. If a squash sets on two fruits pretty close together, say one fruit had a lot of low viability embryos from cross species pollen and the other has more viable seeds because the bees brought the right pollen, the low embryo count fruit gets aborted. Does this happen? I can't prove it but I suspect it strongly.