Oh dear, here’s another agrobiodiversity documentation project that we’ve missed. Over the past few years NordGen has been supporting the Norwegian Genetic Resource Centre in describing apple varieties. That much I can make out in the Google translation of the original Norwegian web page describing the project. But not much more than that. For some reason, the translation is much worse than is usually the case. Maybe it’s the technical language. Anyway, I don’t think there are any data online yet, but when they are, they may or may not be integrated into the database of Danish apple varieties that NordGen manages, complete with handy key. Which is also in English.
India gets its PGR data online
I’m not entirely sure how we missed that data on India’s enormous germplasm collection is now online. While this is welcome, I think it’s fair to say that NBPGR’s PGR Portal still needs some work in terms of user experience. It took me a while to figure out, for example, that if you type a letter under “Crop/Plant Name,” in Passport or in Characterization and Evaluation Search, you get a list of crops beginning with that letter, which you can then choose from. 1 Once you do that you get a list of taxonomic names to choose from, but you can only select one at a time to do your search. And why no rice data at all? There is a nice way of looking at the distribution of different character states for each characterization and evaluation descriptor, but no mapping facility. And you can’t use the portal to order germplasm. To do that you have to fill in a form, which makes no mention of the International Treaty on PGRFA or its SMTA, and email it in. And there are some funny restrictions on use: “All users can search and see the desired information. only registered users can copy and download.” But I couldn’t find a way to register. So, good to see, though clearly a work in progress. Will follow its development closely, and hope to see it link up with Genesys in due course, joining the CGIAR, European and US genebanks.
Nibbles: Disasters, Quinoa, Filipino fruit, Cape Verde nutrition, ICARDA lentils, Ecosystem services
- Sweet potato cuttings to the rescue in Fiji. Hope there’s a nice mix of varieties.
- Quinoa: and so it begins.
- Filipinos not eating their fruits. Bad for Filipino health, no doubt bad for Filipino agrobiodiversity too.
- Maybe they should look to Cape Verde?
- ICARDA waxes poetic about lentils.
- Ecosystem services mapping projects go online. Or they will do, eventually. Just a survey for now. Should that include in situ CWR conservation projects? Now’s your chance to have your say.
Zeolite vs Silica Gel: Deathmatch
The Horticulture Collaborative Research Support Program at UCDavis has a nice factsheet out about Zeolite Desiccant Beads. Why?
Zeolite beads, used with airtight containers, are a simple, inexpensive and widely adaptable method for drying horticultural seeds and maintaining high seed‐quality during storage. The beads can be reused by baking between use.
And of course we know that’s important:
In tropical climates, high humidity causes rapid seed deterioration, resulting in poor stand establishment, lower productivity, less value and disincentive to invest in improved seeds.
Although farmers seem to be the clients here, I thought perhaps this might be a good, relatively low-cost solution for genebanks too, so I ran the factsheet past some seed experts at Kew and IRRI. Thanks to both of them for allowing me to quote them.
It turned out that Fiona Hay, formerly at the Millennium Seed Bank at Kew and now at IRRI, has had quite a lot of experience with zeolite.
Indeed, we have done some work on these zeolite (=molecular sieve) drying beads on rice … in collaboration with the company, Rhino Research, in Thailand that is marketing them (and holds the patent — I’m not sure in which countries). See attachment..
Yes, they are a good desiccator, my concerns are that they could be too good and that they don’t appear to work as described — they don’t take up the same amount of water from the seeds as they do when they are placed over water. This means that is isn’t obvious how to calculate the right quantity of beads to use to dry seeds to a required moisture content. This is based on our work on rice (three different fresh seed lots), but seems to be at odds with what Kent Bradford (UC-Davis) has found for horticultural crops.
In terms of their use by farmers — I don’t think this technology is what they need. If the HORTCRSP project helps them to understand the need to dry seeds, OK; but there may be cheaper, simpler options.
They could be of more use in a genebank situation — once we know how to use them optimally. We are doing more work on this. One of Rhino’s latest products using the beads are bins containing a core of beads which is in contact with some indicating silica gel. Seeds are put in the bin and the silica is used to know when to regenerate the beads. This could be useful for genebanks without proper drying and/or storage facilities. I’d like to get hold of a couple of these to try them out.
Robin Probert at the Millennium Seed Bank then added:
What annoys me most about the USAID fact sheet promotion of Zeolite beads is that it brags the value of Zeolite beads over silica gel for small farmers drying seeds for sowing. We have known for decades that the problem facing local farmers is the rapid loss in viability that can occur if seeds remain at high ambient relative humidity combined with warm temperatures. We also know that if farmers were able to dry seeds from say 80% equilibrium relative humidity (eRH) to below 50% eRH, seed longevity would be improved by several fold. This could mean the difference between seeds surviving for only a few months to a few years.
The fact sheet boldly states (with a nice graph to make the point) that ‘Zeolite beads are more effective than silica gel in absorbing water at low relative humidity’. But this could be written another way: ‘silica gel is more effective than Zeolite beads in absorbing water at high humidities’. Fiona’s work published in Seed Science and Technology last year [Fig 5 in Hay et al (2012) SS&T 40, 374-395] elegantly confirms this.
What this means is that a farmer would need less silica gel than Zeolite beads to dry seeds from ambient humidity to a safe moisture content for short-medium term storage (≤ 50% eRH). But what about cost? The USAID leaflet states that Zeolite beads can be bought for 10-20 US $ per Kg. We buy silica gel beads that we use in our drying drums designed for small-scale seed drying for less than 10 US $ a Kg.
Using Zeolite beads to dry seeds down to very low moisture contents for long-term storage is a different matter and as Fiona’s paper demonstrates, Zeolite beads may have it over silica gel for this purpose. However, as the paper also points out, calculating the weight of Zeolite beads needed is not straightforward and compared to silica gel there is a much greater risk of over drying.
All in all, I know where my money is.
So it turns out that, on balance, according to these experts at any rate, the Zeolite beads may actually be more promising as a solution for resource-strapped genebanks around the world than for seed-saving farmers in the humid tropics. Which was, however, presumably not the aim of the USAID-supported project that came up with that factsheet. But let me tweet this to HortCRSP and see what they say. Stay tuned…
Banter about cucurbits
Mary Beard, classics professor at Cambridge and effective general-purpose public intellectual, knows how to get your attention:
Sikyonians … were a sort of Greek footwear, but also a famous variety of cucumber and so a comic term for a phallus, and the ‘scarlets’ are a suspicious match for the scarlet dildo…
That’s from a review, enticingly entitled Banter about Dildoes, 2 of a book on Roman shopping with a much more boring title. 3 Well, I defer to Prof. Beard on Greek footwear and Roman sex toys, but I’m not so sure about that cucumber.
To see why, let’s turn to a 2007 Annals of Botany paper The Cucurbits of Mediterranean Antiquity: Identification of Taxa from Ancient Images and Descriptions, by Jules Janick et al.:
Many of the Renaissance botanists identified the cultivated sikyos of the Greeks as cucumber. Observers of more recent times, including de Candolle (1886), Sturtevant (Hedrick, 1919) and Hyams (1971), have concurred. However, as de Candolle (1886) admitted, the origin of cucumbers is the foothills of the Himalayas. Although Roberts (2001) identified two ancient mosaic images as depicting cucumber (see Figs 3E and and 4B) the former is clearly Cucumis melo, as evidenced by the longitudinal split in the fruit, and the latter is Lagenaria siceraria, as evidenced by the obviously swollen peduncular ends of the fruits. Archaeobotanical records include findings of several seeds purportedly of cucumber, but it is extremely difficult, even for experts, to differentiate between the seeds of C. sativus and C. melo (Bates and Robinson, 1995). Possibly, an identification of the species of these seeds could be accomplished by analysis of ancient DNA (Gyulai et al., 2006). In this survey of Mediterranean iconography and verbal sources of Roman times, we have found no hard evidence of the presence of cucumbers. There is some linguistic evidence that they became known in the region during the early Middle Ages (Amar, 2000) but the earliest European image known to us of what can be unquestionably identified as cucumber is from approx. 1335, post-dating the Mongol invasions. Renaissance depictions of cucumbers, although very common, show much less variation than do those of melons, which is suggestive of their being more recently introduced or of their lesser culinary appreciation or economic importance.
I think it is worth reproducing those mosaic images. Hopefully Annals of Botany won’t mind. Here’s 3E, the slitty Cucumis melo.
And here’s 4B, the knobby Lagenaria.
So, one can understand the mistake, but, pace Prof. Beard, that “famous variety of cucumber” was probably a famous variety of something else, either a muskmelon 4 or a bottle gourd. Though, as you can see from the illustrations, 5 that wouldn’t affect its comic potential. On the contrary…
PS Incidentally, since we’re talking funny-shaped cucurbits in history…