- Dr Roland Bourdeix is the new COGENT Coordinator.
- Early American hunter-gatherers ate maize.
- Dogfish Head crowdsources a new beer. And it’s got NUS. Rejoice.
Solving broomcorn millet
Broomcorn millet is a bit of a puzzle. You start to get archaeobotanical evidence for cultivated Panicum miliaceum in both China and Europe at about the same time before 7000 BP.
Independent domestication or transmission along the fabled Silk Road (like wheat)? And if the latter, in which direction? You can hear the conundrum set out in more eloquent terms by the eminent archaeologist Prof. Colin Renfrew in this talk from last March, from which I’ve nicked the figure. You can just go to about 20 minutes in. But do yourself a favour and watch the whole thing.
Anyway, Prof. Renfrew mentions that genetic work is underway on Panicum which promises eventually to clarify the situation. And here it is. And, alas, interesting as it is, it doesn’t, not much. The paper in Molecular Ecology by Harriet Hunt and others looks at new microsatellite data on 98 landraces from across Eurasia obtained from genebanks in Russia, the US and Japan, and from new fieldwork in Inner Mongolia. ((HUNT, H., CAMPANA, M., LAWES, M., PARK, Y., BOWER, M., HOWE, C., & JONES, M. (2011). Genetic diversity and phylogeography of broomcorn millet (Panicum miliaceum L.) across Eurasia Molecular Ecology DOI: 10.1111/j.1365-294X.2011.05318.x))
The researchers find evidence for two largely distinct genetic clusters, or genepools, one centered on China and one in Europe. And indeed of sub-clusters within each genepool. But they can’t use any of these data, even when combined with the archaeobotanical data, to distinguish between the separate domestication and Silk Road hypotheses. ((Actually, might not both be right? Might not simply the idea of domestication of this species travelled along the Silk Road, rather than the crop itself?))
The archaeobotanical and genetic data thus currently present a set of signals that are not wholly consistent with either a single or multiple domestication centres for P. miliaceum. Analyses to determine the direction of migration were uninformative for our data set.
Bummer. Ah, but there is hope: the wild relative!
The genetic picture would be clarified by comparison of landrace genetic diversity with that of the wild ancestor of broomcorn millet. Analysis of microsatellite diversity in P. miliaceum subsp. ruderale could determine whether this subspecies is indeed the wild ancestor of the domesticated form, in which case the former would be expected to maintain a more diverse genepool, or a derived feral type, whose genetic diversity is a subset of domesticated P. miliaceum.
So what’s stopping them?
We did not include any samples of P. miliaceum subsp. ruderale in the current study: Although morphotypes fitting the description of this taxon are reported as being widespread across the Eurasian steppe (Zohary & Hopf 2000), detailed information or samples are not easy to find. For example, P. miliaceum subsp. ruderale is not listed on the http://www.agroatlas.ru website, and no specimens are identified as belonging to this taxon in the extensive herbarium collection of P. miliaceum at the Royal Botanic Gardens, Kew. Appropriate field collections of weedy forms of P. miliaceum for genetic comparison with cultivated types are needed, but the necessary fieldwork across vast areas of Eurasia, to give a sample set from which reliable conclusions could be drawn, would require a major international collaborative project. Our demonstration of strong phylogeographic patterning in cultivated P. miliaceum makes fieldwork and sampling of P. miliaceum subsp. ruderale a high priority for further investigation.
Well, I know what they mean, but it’s not quite as bad as that. There are in fact 10 accessions labelled P. miliaceum subsp. ruderale in Genesys, originating from 8 countries and conserved in 4 genebanks in Europe and the USA. ((Incidentally, those genebanks strangely don’t include ICRISAT’s. Need to check that.)) Not a great haul, but a “major international collaborative project” has to start somewhere.
Nibbles: Chickens, Millet adoption, Specialty crops, World Food Day, Migrating forests, Vietnamese pheasants, Yews, High prices, Genebank tour, Climate change conference.
- Why did the Chinese chicken cross the road? To get a new date. For domestication, that is.
- The Indian Farmer is actually three, millet-wise.
- USDA wades into specialty crops. Wonder if one of them is baobab, and a factsheet is involved. Or “small scale grains” for that matter.
- “Life in the countryside is hard.” But fear not, FAO is on it.
- Forests are not migrating. Species are actually undergoing range contraction at both ends. Well that’s weird.
- The first pheasant extinction? Say it ain’t so.
- I like pictures of old trees. So sue me.
- Jess stops traffic.
- Tour a cocoa genebank. Could this catch on?
- International Conference on Climate Change and Food Security (ICCCFS). Not hot air.
Brainfood: Ectomycorrhiza, Synthetic peanuts, Ancient Greek amphorae, European bison, Pea breeding, Animal domestication
- Ectomycorrhizas and climate change. One more damn thing to worry about.
- Meiotic analysis of the hybrids between cultivated and synthetic tetraploid groundnuts. It’s normal. The meiosis I mean. Why isn’t this sort of thing done with more crops?
- Aspects of Ancient Greek trade re-evaluated with amphora DNA evidence. More than just wine and olive oil.
- Reconstructing range dynamics and range fragmentation of European bison for the last 8000 years. More eastern and northern than thought, and more affected by the spread of farming than climate change in the Holocene.
- Resistance to downy mildew (Peronospora viciae) in Australian field pea germplasm (Pisum sativum). It comes from Afghanistan.
- Deciphering the genetic basis of animal domestication. Despite all that selection and all those bottlenecks, they really are diverse.
Don’t forget the open Mendeley group for the papers we link to here.
Nibbles: Ethnobotany talks, Cannabis taxonomy, Ag blogging, Breadfruit in Hawaii, Heirloom auction, Iron Age boozer, Andean potatoes, Minor crops conference, Insects as food
- And if you can’t get to Kew, how about an ethnobotany talk in Denver, Colorado? Or maybe one on GPS and plants, same venue? Can’t make either? Watch a lecture on Schultes in the Amazon. He’s the Father of Ethnobotany, after all.
- Misclassification of Hemp Holds Back Industrial Applications. Duuuuuuuuuude.
- Write a blog on youth and agriculture, win big money. Yeah, right, I’ve heard that one before… I’m still here, Sergey.
- Hawaii’s Breadfruit Festival is coming! So get in the mood.
- Sotheby’s auctions heirloom. No, really. Alas, probably no breadfruits.
- Now, what can I say about Scotsmen and pubs that won’t be construed as a racist slur? Probably nothing.
- Old potatoes helping Andean farmers cope with climate change. And, no doubt, obesity too.
- Conference on pesticide use on minor crops. Oh, to live-tweet that one.
- Micro-livestock makes it into the New Yorker. Can the backlash be far behind?