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Author Topic: The Yam Checklist: Starting a Backyard Dioscorea Germplasm Collection  (Read 117 times)

Caesar

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Well, I think I finally cracked. I went too deep, and now I mostly have yams on the brain. But that's okay... I'll never go hungry with a good yam collection.  ;)

Having read the 6 documents of "Tropical Yams and their Potential", as well as other sources, I've come up with a list of yams that I'm looking to collect, multiply and disseminate to other growers (these are marked with a checkmark: ✓). I've also listed a couple of other yams that are deemed edible by the literature, but that don't strongly catch my attention (also marked with a checkmark anyway: ✓), have been outright rejected (these are marked with an X), or have poorly-known qualities regarding their edibility (asterism: ⁂ ).

The Big 5 (or 8, depending on how you segregate the species): ✓
1 - D. rotundata (White Guinea Yam) + D. cayennensis (Yellow Guinea Yam)
2 - D. alata (Greater / Winged Yam) + D. purpurea (Ube / Purple Yam)
3 - D. bulbifera (Asian Air Potato) + D. latifolia (African Air Potato)
4 - D. esculenta (Lesser / Potato Yam)
5 - D. trifida (Cushcush / Mapuey Yam)

The Lesser 5:
1 - D. pentaphylla (Five-leaf Yam) - ✓
2 - D. transversa (Australian / Pencil Yam) - ✓
3 - D. nummularia (Pacific Yam) - ✓
4 - D. dumetorum (Trifoliate Yam) - ¿✓?
5 - D. hispida (Intoxicating Yam; also known as D. reticulata) - X

The Temperate 3: ✓
1 - D. polystachya (Nagaimo / Chinese Yam; also known as D. oppositifolia & D. batatas)
2 - D. japonica (Japanese Yam)
3 - D. hamiltonii (¿Nameless? I'd just call it Hamilton's Yam)

The Leftovers? (not a great name, but  don't know what else to call 'em; it doesn't mean they're of bad quality):
1 - ¿D. pseudo-tomentosa? (¿Nameless?) - ✓
2 - D. remotiflora ("Camote de Cerro" / Mexican Mountain Yam) - ✓
3 - D. dodecaneura (Ornamental Yam) - ✓
4 - D. orangeana (¿Madagascar Yam?) - ⁂
5 - D. brachybotrya ("Papa Cimarrona" / "Jaboncillo") - X
6 - D. humifusa ("Huanqui") - X
7 - D. deltoidea (¿Nameless?) - X
8 - D. rupicola (¿Elephant's Foot?) - ⁂
9 - D. altissima (Dunguey) - ⁂
10 - Rajania cordata ("Ñame Gulembo") - ¿X?

I'm currently growing D. rotundata, alata, purpurea, bulbifera, trifida, and polystachya. I have some possible sources to check out for D. esculenta, japonica, latifolia and additional strains of bulbifera. D. cayennensis eludes me, but though I'm sure it's here in Puerto Rico, it's not common nor easy to find (if anyone has some, send 'em my way).

I recently received a mystery yam in the mail from eBay, but it arrived so thoroughly dried out that I don't expect it to survive (though the vendor assures me that it should or they'd reimburse me, which I declined); nevertheless, I planted it anyway and hope against hope that I'll get something out of it. It was sold as a D. pentaphylla, but the vine photos reminded me of alata, and the bulbil photos resembled bulbifera. The vendor confirmed it was not pentaphylla, but I bought it anyway 'cause it was cheap and I felt like trying it out. At any rate, the vendor confirmed that it was fully edible, bulbils-and-all, so I considered it valuable anyway. If it survives, I hope to be able to deduce the species from the anatomy.

I have some D. hamiltonii seeds coming in the mail, as well as some true pentaphylla bulbils. When asked about the pentaphylla bulbils (as opposed to the tuber), the vendor said they don't eat them, but they never explicitly confirmed that they were toxic. I'd really like to know if they're edible, but since there are toxic pentaphylla strains out there, I'm reluctant to try them; if I could find a lab able and willing to analyze a cooked sample, I could lay that doubt to rest. The tuber was confirmed to be edible steamed.

There's another mystery yam coming in the mail, sold as D. pseudo-tomentosa. I couldn't find anything in the literature about this species being edible (or toxic), only that it's endangered. The photos of the yam may have vaguely resembled D. esculenta, but I may be reaching with that conclusion. Truth be told, I'd love for it to be genuine D. pseudo-tomentosa, to add another good species to the germplasm. Link here.

D. transversa is very high on my wish list (specifically the large-tubered bulbil-bearing strain), but no luck finding it yet. No idea where to find D. nummularia (which is said to closely resemble rotundata), but I also consider it important as a supposedly good-quality species. Interestingly, one document claimed that some nummularia cultivars were introduced to Puerto Rico; also, there seems to be some confusion in the literature whether to consider the cultivar "Wael" as a type of transversa or of nummularia.

I don't object to D. dumetorum if I can obtain it, but I'm not really looking for this one. The best strains still seem like poor quality yams and they have to be eaten quickly after harvesting or they turn hard (even after cooking) and difficult to peel (as if their strange shape didn't already make that a challenge). The worst strains are downright toxic, which leads me to its close relative... I don't even know how D. hispida made it into the original documents. I don't even care that they have in-fact been eaten before (and they're probably still eaten to this day), even the best strains are dangerously toxic and require jumping through hoops to detoxify and turn them edible, and we all know how I feel about that... Famine food. So I just mentioned it for completion's sake, but I don't consider that species edible, nor am I interested in it in the slightest.

D. remotiflora is an edible wild mexican yam that barely even has a presence in the literature. If it weren't for a single isolated YouTube video (link here) showing its harvest, I wouldn't even know this species was edible. It seems to bear some resemblance to D. polystachya, which is also referred to as "Camote de Cerro" in Mexico. As it seems to be rare and difficult to find, with few traits to explicitly recommend it, I won't go out of my way looking for it. But if someone out there has some and is willing to share, I'd be very grateful nonetheless.

D. dodecaneura doesn't seem like an especially important species, but it is listed in several sources as being edible raw or cooked with an almond-like flavor; it's also a beautiful ornamental. I'm kinda interested in it. A few links: Link 1, Link 2, Link 3

D. orangeana is Madagascar's only edible native Dioscorea, and is a recent discovery. I've yet to find an online source that knows anything about it, or if it's even conventionally edible (as opposed to a hispida-like famine food). Unless it's explicitly confirmed as conventionally edible, I'm not too interested in it (and even then, it's like remotiflora, where it's so rare I'm not sure it's worth going out of my way for it).

I saw brachybotrya, humifusa, deltoidea and rupicola on a YouTube video (link here) where a guy was trying to germinate them from seed (along with other rare supposedly edible species... like reticulata/hispida). When checked online, the Chilean brachybotrya & humifusa turned out to be toxic and bitter (¿saponins?), and probably require special preparation, so I'm not interested in either as a crop. Deltoidea from Asia was also said to be bitter but edible in PFAF, though the article (link here) urged caution, and mentioned that it's boiled with wood ashes to remove bitterness. It doesn't seem like a good prospect either, so I'm not interested. Regarding rupicola, I could barely find anything about it online, but one seed seller claims it to be edible (link here). I couldn't see the details because when I clicked the link it failed to open for me. Maybe the link will work for one of you and you can post the screenshot. At any rate, I'll be interested if it turns out to be conventionally edible, but as a desert plant I doubt it'd be particularly prolific as a crop, so I probably wouldn't go out of my way for it anyway.

Edit: Another species:
D. altissima was present in another seed sowing video. There's not much in the literature about it, but it's apparently wild harvested and occasionally home grown for its edible tubers in parts of its native range in South America; it's also present in Puerto Rico. A photo search revealed a very thorny stem and small aerial bulbils. I wouldn't grow it from anything other than seeds, for fear that it might carry the same virus as R. cordata, but since there's no details available on preparation & toxicity level (¿Conventionally edible? ¿Detoxification necessary?), I'm not too interested in trying it... Maybe a little. Info link here.

And finally, Rajania cordata, our very own Ñame Gulembo. It's a close relative of Dioscorea. I don't recall having tasted this one (though I might be mistaken). I'll have to ask around for am account of its flavor, but my grandmother mentions that it is fibrous. It grows wild in the mountains of Puerto Rico and is wild-harvested here. So why have I rejected it? Because it is a carrier of a virus that is a very nasty disease of D. trifida (and also affects other species, to varying degrees). That's a big risk for a crop that's probably not very decent (though it requires no special preparation). Why the question marks? Well, I've yet to find out if the seeds carry the disease. If they don't, I wouldn't mind trying my hand at this species. But first I need assurance that I'm not endangering my other yams before I'd be willing to even consider it.

***

So this is a taste of what I wish to achieve. There's a lot of edible yam roots out there, and I wanna grow as many as I can, especially the better types, and help get them to other interested growers. It seems absurd to me that something as widespread, productive and gastronomically wholesome as the air potato was so hard for me to find in the first place. And it seems even weirder that other good yams (which don't have the same legal issues) seem even harder to find. So let's get a good germplasm collection up and running to get these species into the hands of other hobbyists. The more people join our exchange network, the better.
« Last Edit: July 07, 2018, 09:12:05 AM by Caesar »

Luisport

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WOW!!! You are The Yam King!  ;D
Thank you very much for this great info!

Caesar

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Haha, the Yam King... I like the sound of that. But surely the original document authors have me beat in that regard. I remember that when I first got into agriculture, having decided to become a farmer, I'd facetiously tell my friends that my work would be growing yams in the hillsides. I never imagined that I'd actually be dreaming of doing just that. Oh well, yams are only part of it, I love all edible crops. I hope I'll be able to get a piece of land soon.

I took some photos of the backyard, particularly the yam trellises. Please disregard the mess, I need to clean up soon.  ;)

Here's the pvc trellis, still under construction (just a couple of posts so far). I'll add some t-jointed side bars on top, and link everything with clotheslines. I'll also link it to the bamboo trellis, with which it's perpendicular at the corners.


Here's the bamboo trellis, with some very vigorous bulbifera vines reaching past it and into the big pigeon pea bush in the side yard... They'll be reaching the Açaí palms soon!


The bulbifera tote (six plus the original rotundata and a trifida), the tomato tote (with a second rotundata strain, a trifida and the two alatas - one of them the purpurea strain) and the Lerén tote (three of these, with four potato mints and six trifidas):



And a nice view of the rotundata growing up alongside the bulbifera:


I'll be adding more totes over time, as well as a few buckets for those that I'd like to grow more isolated or compact (like the polystachya & hamiltonii). The green tote off to the side (currently housing some turmeric that I'll move to the ground) will house the Hodgsonia vines.

***

I forgot to post a pic of my dried up mystery bulbils, so here it is:


And the links to the pentaphylla bulbils (I bought the first one):
Link 1, and Link 2.

Also, either I misread the information or it was outdated, because I found two to four extra Yams from Madagascar that are allegedly edible: D. acuminata and/or D. maciba, and D. alatipes and/or D. bako.

Luisport

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Hi! That's great! But this bulbs rehidrate and growth?

Caesar

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I did rehydrate them prior to sowing, but my concern was the extent to which they were dried, the fact that some were apparently squished in the package, and the fact that all of them had already sprouted, and the sprouts were nothing but dried twigs at this point. They'll probably succumb to rotting, but I'm still praying for a miracle.

I got my D. hamiltonii seeds yesterday, I think there were like 30 in the package. I planted 10 in a jar covered with plastic wrap to preserve moisture, and soaked the rest, per the instructions. I'll be planting those soon in a plastic pot.



D-Grower

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You are the yam King! Agree with above poster.

I too am into yams but haven't been able to source many varieties that are edible. Only have the D. alata purple type and D. opposita. Would love any you could share! I'm going to make a post shortly with a list of plants I have available. Maybe we could trade???

DG
Trying to grow it all!

Caesar

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You are the yam King! Agree with above poster.

I too am into yams but haven't been able to source many varieties that are edible. Only have the D. alata purple type and D. opposita. Would love any you could share! I'm going to make a post shortly with a list of plants I have available. Maybe we could trade???

DG

Definitely! I'll have material available as soon as the vines die back, maybe somewhere around November - March.

I managed to contact the local Ag. Station in Corozal, where they apparently specialize in Yams. I'm not sure how many varieties they have, but they explicitly confirmed that they have several varieties of D. esculenta, as well as several each of D. alata, D. rotundata and D. trifida. They'll have stock ready later in the year as well, which I'll acquire and plant for next year. I'm gonna give them some of my bulbiferas, so they can evaluate the variety as well. If I give them a bulbil, they won't be able to give it a fair shot until the year after, but if I give them an in-ground tuber, they should get a mature productive vine in their first year. Hmm... I think I can spare a tuber.

Speaking of my bulbifera, I reviewed parts of TYATP (Tropical Yams and their Potential) again, and I'm fairly confident that my bulbifera is varietas "Sativa". Of the asian bulbiferas, there are four varieties: two small-bulbilled wild types (distinguished from each other by leaf shape), Suavior (which is characterized by prominent lenticels on large mature bulbils), and Sativa (which is characterized by smooth-skinned large mature bulbils). Mine only had noticeable lenticels during early development, but they always matured smooth. Incidentally, TYATP explicitly stated that the bulbiferas from India and South East Asia were both tastier and way more productive than the African bulbiferas (the ones I prefer to call latifolia, to distinguish them). It kinda makes me wonder why the African types appear to be more common among those growing bulbiferas. Also, they had a table with data collected from a large collection of different bulbifera cultivars (now defunct, curtesy of the USDA, to which it belonged), and their Sativa accession (from India, like my own) far outproduced all other cultivars, even other Asian types. The only one that produced more bulbils was a New Caledonian type, which thoroughly underproduced the in-ground tuber (unlike Sativa, which was a good producer of tubers). I'll post screenshots of the relevant pages:




Another fact I recently learned from these documents is that D. hamiltonii (which I'm now trying to germinate) is a close relative (and probable ancestor) of D. alata. I didn't expect that, given its tolerance for cooler conditions than alata. Then there's the fact that some types of D. rotundata can be cropped twice in one year, which is something I'd like to try myself. Relevant pages here:



And



I'm quoting and posting all these screenshots, and it hadn't occurred to me to post the original documents, so here they are, in full downloadable PDF glory: Tropical Yams And Their Potential, Parts 1 - 6:

1. D. esculenta.

2. D. bulbifera.

3. D. alata.

4. D. rotundata & cayennensis.

5. D. trifida.

6. Minor Dioscorea Yams.

D-Grower

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Very awesome man! Just let me know when you have anything ready to trade/sell. I'm down for any and all edible yam varieties. You've done the work I've planned to do for some time. I'm a survival gardening minded guy and seek to have many varieties in the event of who knows what. Yams are perfect for such application being that they need very little attention over time with potential to be heavy producers. Got other root veggies that may interest you whenever.

DG
Trying to grow it all!

mangaba

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 I have some varieties of yam in my garden. Is there any manual/book describing the varieties which could help me to classify my varieties ?

Caesar

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Very awesome man! Just let me know when you have anything ready to trade/sell. I'm down for any and all edible yam varieties. You've done the work I've planned to do for some time. I'm a survival gardening minded guy and seek to have many varieties in the event of who knows what. Yams are perfect for such application being that they need very little attention over time with potential to be heavy producers. Got other root veggies that may interest you whenever.

DG

Yams are productive and, as far as I'm concerned, the tastiest roots. I'm looking forward to the trade, it'll be the first time I make something available forum-wide. I hope I manage to get good material safely to everyone involved.


I have some varieties of yam in my garden. Is there any manual/book describing the varieties which could help me to classify my varieties ?

The book links I posted in my last post explain the anatomy of the varieties, but I'll sum up the information on the most prominent distinctions. When talking about leaves, I mean the leaves on the upper portion of mature vines. Leaves on the lowest portion, as well as on young vines, can sometimes develop in a different configuration (usually alternate on a vine that otherwise has paired leaves).

Vines that twist to the left (lower right to upper left: the "S" twist):
D. esculenta
D. bulbifera
D. trifida
D. pentaphylla
D. dumetorum

Vines that twist to the right (lower left to upper right: the "Z" twist):
D. rotundata & cayennensis
D. alata
D. nummularia
D. transversa
D. polystachya
D. japonica
D. hamiltonii

Paired Leaves:
D. rotundata & cayennensis
D. alata
D. nummularia
D. polystachya
D. japonica
D. hamiltonii

Alternate Leaves:
D. esculenta
D. bulbifera
D. trifida
D. transversa
D. pentaphylla
D. dumetorum

Pentaphylla leaves are divided into 5 leaflets, dumetorum into 3, the rest are singular. Trifida leaves are somewhat palmate, and other than the rounded leaflets of pentaphylla and dumetorum, the rest are heart-shaped (with varying ratios of length-breadth and varying degrees of rounded to angular corners).

Trifida, alata and hamiltonii stems have ridges/wings (which can be substituted by corresponding ridges of spines in some varieties of alata). Rotundata, cayennensis, esculenta, pentaphylla and dumetorum stems tend to be spined or prickly; the rest are smooth (though some species, like nummularia, can have prickles at the base). Bulbifera and nummularia have round stems, polystachya has a square stem. Dumetorum is highly pubescent/fuzzy.

Bulbifera has round bulbils (usually large, but tiny ones are also produced), polystachya and japonica bulbils can be round or oval, and are always small. Alata bulbils are ovoid to long & irregular, and are small to medium sized. Pentaphylla bulbils (allegedly not edible) are small to medium sized and horseshoe shaped, and dumetorum bulbils (probably toxic) are spiny. I'm not sure how transversa bulbils are, but only some varieties produce them. The rest don't usually produce bulbils. Bulbifera is a reliable producer of bulbils, whereas not all varieties of alata produce bulbils (and those that do aren't usually as productive as bulbifera).

Those are the main distinctions, but there's always variation among the species listed, never mind those that I didn't get to list, which should have further differences. Can you take closeup pictures of your vines? Leaves, lower and upper stems and how the stems curl? They might be easy to identify right here.

*

My Ube kept declining, so after examining the roots (which already had a new tuber forming, with the old tuber not fully deteriorated) I cut the vine to a stump (hoping for it to branch, or for a new one to form from the base) and replanted it in a small pot for observation. I accidentally knocked off the old tuber, and I'm really hoping I can get a second vine from it.

The first mystery yam bulbils have rotted away. Only two remain, and I think they'll rot soon enough. The second mystery yam (sold as D. pseudo-tomentosa) arrived in the mail, suspiciously packaged identically to the first mystery yam, despite being a separate Thai eBay seller. That said, while dry, they definitely seemed to be in much better condition, and even seemed to have some sprouts forming. I'm cautiously optimistic that I'll get them to grow without losing them. Here's some pics:



The pentaphylla bulbils have yet to arrive, and I'm a little worried about the state they'll be in. I'm also waiting on an alata (which I bought thinking I'd get a dumetorum due to the photos used), a cayennensis, and some non-Dioscoreas: an Elephant-foot Yam (Amorphophallus paeoniifolius), some Ensete ventricosum seeds and Roy's Hogdsonia seeds. It's exiting to expect something in the mail every day, and a little nerve-wracking (you'll never know when it'll arrive and in what state it'll be in).

 

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