|
|
Post by gilbert on Dec 26, 2017 18:57:47 GMT -5
Here are my thoughts on a different approach to "sweet potato" breeding for cold climates.
There are several hardy wild species that grow in the USA. Some of them are edible, but it does not sound like they are excellent. It would be nice if they could be crossed with the sweet potato. However, they are all diploid, with thirty chromosomes. Sweet potatoes are hexaploid, with 90 chromosomes. This means that any such breeding project would be difficult.
What if instead, we focused on diploid species? I've done some research and the following are promising; two edible tropicals, and three sort of edible hardy species. They might cross; I can't find anybody having tried it.
Would this be easier than working with sweet potatoes themselves? Could we simply create a parallel, similar species? Are there other edible diploid species that could work?
Ipomoea costata, bush yam: Edible, tastes like sweet potato, Australian, can only take a light frost; grows wild; 30 chromosomes, self compatibility unknown
Ipomoea lacunosa, whitestar potato: edible (not sure how edible; native peoples used it on a small scale), Eastern and Central USA, cold-hardy Chromosome number 30, self compatible
Ipomoea pandurata, manroot: sort of edible (people disagree on how much, may be somewhat toxic, laxative, bitter, etc.) big tap root, hardy, Eastern and Central USA, Chromosome number 30 self incompatible
Ipomoea aquatica Water spinach: aquatic; invasive; no significant tuberous roots, edible leaves, tropical, Chromosome number 30; self compatible
Ipomoea leptophylla, bush morning glory: edible (but maybe not very, young roots only,) large tap root, drought tolerant, native to Colorado and other western states, Chromosome number 30, self compatibility unknown.
|
|
|
|
Post by billw on Dec 26, 2017 19:24:10 GMT -5
I think I. pandurata is worth a try. I have played around with it a bit. It yields slightly better here than sweet potato, which yields not at all. I don't think that you will end up with something that much resembles sweet potato, at least not in a single human lifetime, but you might get a fairly hardy calorie crop that doesn't taste too terrible.
If one diploid member of the genus is self-incompatible, it is generally pretty safe to assume that all of them are.
|
|
|
|
Post by oxbowfarm on Dec 26, 2017 19:26:55 GMT -5
Sounds cool. I'd say its a huge stretch to call it sweet potato breeding when you aren't using sweet potatoes in the project. Bush morning glory is definitely hardy to moderate frosts.
|
|
|
|
Post by rowan on Dec 26, 2017 21:36:07 GMT -5
I have tried to grow I.costata a few times with no success. If they germinate I can often get them to around 10cm then they die off. They are just too temperamental for my patience at this time.
|
|
|
|
Post by reed on Dec 27, 2017 5:08:07 GMT -5
I attempted to cross I padurata on to I batatas last year. I have five seeds that developed from some of the pollinated flowers. I didn't bag the flowers so I suspect it is more likely the bees pollinated them as well from other I batatas. If any crossing was successful it should be fairly apparent in early stages of growth, I would think. I'll be trying again this year. As far as breeding for cold climates, I'm not sure that isn't possible just by mass crossing and selection. Short maturity time is pretty certainly in reach, assuming there is at least some period of relative warmth. Frost tolerance may even be possible from what I'v seen. Perennial probably not, short of crossing to another species.
[add] I think that because I had some volunteer I batatas come up late in the season, close to frost time. They survived about to where they were getting their second set of true leaves, at least one looked pretty bad but was still alive after a light frost. gilbert , interesting that the research turns up that I pandurata is self incompatible because it is not, not always. It may be like I batatas in that it usually is, often enough so that people think it is but there are exceptions. I located seven wild I pandurata plants this year and six of those did not set a single seed. I collected a full cup of seed from the other one and I'm sure it is the only plant there as I followed it's vines back to where they came out of the ground, at the time considering trying to dig it up.
[add] well I guess I shouldn't say sure, I suppose it is possible that there is another plant within bumblebee distance that I don't know about. Although I would think it would have to be very near to explain pollination of pretty much every flower. And every capsule had the full four seeds, unlike the sweet potatoes which often have just two or three or even just one. |
|
|
|
Post by gilbert on Dec 27, 2017 10:26:07 GMT -5
I suppose it is complicated; would it be something like sweet potatoes, where some varieties are compatible, others are not, and others are only cross compatible with some other varieties?
I guess that is probably true. However, with a perennial crop I would only have to get lucky once, at which point I can multiply it by vegetative means.
Perenniality is fairly important for me, due to wild spring weather. It would be so much easier to just leave the smaller tubers in the ground after harvesting, and let them come up in the spring, with a good store of carbohydrates to fuel quick growth. Also, this would allow for planting in uncultivated, neglected fields, where they could slowly build up a store of tubers; disaster insurance of sorts, or a very low input/low output agriculture. Maybe the fields could even contain a mix of grasses and other plants, and be grazed, with a tuber harvest once every few years as an added bonus.
I also imagine that even in more friendly climates, not having to fuss with overwintering tubers indoors and starting slips would be a big advantage. In fact, some university breeders are working on a sweet potato that can be planted the same way Irish potatoes can, though as far as I know they are not focused on having them overwinter in ground.
That's too bad; I wonder why. Morning glories are supposed to be vigorous! Have you ever eaten any roots?
|
|
|
|
Post by billw on Dec 27, 2017 12:51:34 GMT -5
I suppose it is complicated; would it be something like sweet potatoes, where some varieties are compatible, others are not, and others are only cross compatible with some other varieties? I was speaking only of the diploids. Self-incompatibility tends to break down with polyploidy, although the degree to which this occurs depends on the self-incompatibility system of the species. |
|
|
|
Post by billw on Dec 27, 2017 12:57:23 GMT -5
gilbert , interesting that the research turns up that I pandurata is self incompatible because it is not, not always. It may be like I batatas in that it usually is, often enough so that people think it is but there are exceptions. I located seven wild I pandurata plants this year and six of those did not set a single seed. I collected a full cup of seed from the other one and I'm sure it is the only plant there as I followed it's vines back to where they came out of the ground, at the time considering trying to dig it up. That could be valuable germplasm for anyone trying to work with this species. Ipomoea has sprophytic self incompatibility, which is generally a pretty strict system. Any self-pollination is supposed to fall well below 1%. If that plant self-pollinated, then it likely has some sort of incompatibility defeating mutation. |
|
|
|
Post by gilbert on Dec 27, 2017 15:32:00 GMT -5
That's interesting.
So, my idea of isolated pots of morning glories might be a good one?
How likely are the species listed above to go on a rampage and wreck somebody's yard? Does anyone have experience with them? The Australian species is frost tender, so probably not too dangerous. Do manroot and bush morning glory plants spread by runners, stems, or roots like bindweed does, or do they stay in a clump?
|
|
|
|
Post by reed on Dec 27, 2017 17:18:11 GMT -5
gilbert , interesting that the research turns up that I pandurata is self incompatible because it is not, not always. It may be like I batatas in that it usually is, often enough so that people think it is but there are exceptions. I located seven wild I pandurata plants this year and six of those did not set a single seed. I collected a full cup of seed from the other one and I'm sure it is the only plant there as I followed it's vines back to where they came out of the ground, at the time considering trying to dig it up. That could be valuable germplasm for anyone trying to work with this species. Ipomoea has sprophytic self incompatibility, which is generally a pretty strict system. Any self-pollination is supposed to fall well below 1%. If that plant self-pollinated, then it likely has some sort of incompatibility defeating mutation. I speculated something like that with my self-pollinating I batatas specimens, not that I have any real scientific reason or learning to make me think it. Never thought about it regarding the I pandurata. Everyone I sent I batatas seed to this year also got some seed from that wild plant and I still have plenty. I'v decided the offspring will be named I pondutatas, or I batatarata depending on who the mother is.  gilbert , I'v never heard of the others you listed but the I pandurata seem to be fairly well behaved. They are BIG no doubt about that but tracking back all the long, up to 20 feet, vines on the one I got the seeds from all ended up at a single trunk. What I'm wondering and will find out soon enough is do those vines live through winter or die down and regrow from the root? I think they probable live, cause nothing could grow that big so fast. The vines also did not root down along the way as sweet potatoes do nor did the cuttings I brought home develop any roots. If I try that again I'll use the willow water method I read about. Any idea where to get seeds of some of the others? Having re-read the whole thread I see I misunderstood. It's about creating a new perennial sweet potato like vegetable not really about sweet potatoes. I just get all excited when ever some one mentions sweet potatoes. |
|
|
|
Post by imgrimmer on Dec 27, 2017 18:20:21 GMT -5
|
|
|
|
Post by gilbert on Dec 27, 2017 19:24:48 GMT -5
It looks like they are all available online. Water spinach is not legal to grow in the USA (even though it would only be invasive in semi-tropical conditions; there is no way it could survive a Colorado winter in the wild, and I doubt it would even survive too well in the summer.)
I did find one reference which indicates that the I. pandurata dies back to the crown and regrows each year. If so, that's an amazing vine growth! Both the bush morning glory and the manroot have foliage that is somewhat toxic to grazing animals. One of my goals is to have good fodder production from the tops, as is possible with water spinach and sweet potato.
|
|
|
|
Post by reed on Dec 28, 2017 11:32:23 GMT -5
Well, I'm a little surprised but your reference that I pandurata dies back is correct. I stopped by the plant I got the seeds from and sure enough the vines are all dead and dried up. Amazing it can grow so big each season. I guess it must be true that it makes a giant root, it would need it to support that much growth so fast.
|
|
|
|
Post by gilbert on Dec 28, 2017 12:31:25 GMT -5
I. costata seed is quite expensive. Some sources are selling it for almost 50 cents a seed, before shipping. And if they are weakly germinating, as stated above, then that is even worse. I did find one source that seems more reasonable, sixteen dollars for a few hundred seeds.
Do you suppose I'd need a Phytosanitary or import permit for that variety? Where would I find out?
That is amazing about I. pandurata, but it makes sense; I wonder if any Convolvulus have frost tolerant vines, I'd guess not. Even bindweed waits to sprout back up till the soil is warm.
|
|
|
|
Post by gilbert on Dec 28, 2017 13:14:44 GMT -5
The government website is so complicated I can't tell for sure! Looks like I would, since there are more than 50 seeds in a packet. The certificate would be expensive. Buying a bunch of seed packets with 8 seeds in them for 4 dollars a piece would also be expensive.
|
|
