- Getting to grips with citrus greening.
- The fabulous church forests of Ethiopia. But are women involved?
- Three articles on why the African Green Revolution won’t be like the Asian one.
- Whatever happened to the Esopus Spitzenburg?
- Papua New Guinea ratifies the ITPGRFA.
- African indigenous vegetables for development. Hey, I’m doing my part.
- Cassava is naturally climate-smart, but yields still not rising fast enough.
- Great video on the origin of maize.
Bottleneck slides
Try and find an illustration of the domestication bottleneck — to put in a slide for a presentation, say — and likely as not you end up with some variation on a classic theme, this particular version being from the great Teacher-Friendly Guide to the Evolution of Maize:
That’s fine for some purposes, but sometimes you want real data, and then you might use this:
But I don’t really find that particularly striking, do you? And that’s why I really got excited about Fig. 1c in a recent paper about patterns of genomic diversity in a bunch of soybean accessions, ranging from wild populations to modern varieties. It’s really tiny in the paper, so I’ve blown it up here, at the expense of some quality:
I think this really shows very compellingly how the genetic diversity space shrinks and shifts as you move from wild soya to modern varieties. You don’t even really need to know that the axes are principal component scores or indeed how diversity was measured. But is this kind of diagram common out there? I can’t remember seeing anything quite this clear, and some rapid googling drew a blank too. Well, perhaps I read the wrong journals.
So here’s a question for you: what’s your favourite illustration of the domestication bottleneck, using real data? If we get a decent number of examples, I’ll try to put them all together in a post, and maybe even organize a vote.
Brainfood: Amorphophallus diversity, Physiological phenotyping, Jatropha diversity, Ass origins, Prickly lettuce diversity, Sugarcane in vitro, Pennisetum diversity, ABS and Norway, Seed storage behaviour, Barley diversity, Lentil diversity, Bilberry characterization, Potato genomics, Asian horse ABS
- Cytotaxonomic investigations to assess diversity and evolution in Amorphophallus Blume ex Decne. (Araceae). Out of 25 accessions and 7 wild species, “A. dubius may be the immediate ancestor of cultivated forms.”
- Physiological phenotyping of plants for crop improvement. High-throughput phenotyping is only the start.
- Geographic origin is not supported by the genetic variability found in a large living collection of Jatropha curcas with accessions from three continents. 900 global accessions fall into 2 genetic groups, but not related to geography.
- Genetic diversity of donkey populations from the putative centers of domestication. Sudan and/or Yemen.
- Genetic and Biochemical Evaluation of Natural Rubber from Eastern Washington Prickly Lettuce (Lactuca serriola L.). I look forward to seeing those rubber lettuce plantations.
- An approach on the in vitro maintenance of sugarcane with views for conservation and monitoring of plant nuclear DNA contents via flow cytometry. It’s possible to conserve sugarcane in vitro, but it won’t be straightforward.
- Geographical Gaps and Diversity in Deenanath Grass (Pennisetum pedicellatum Trin.) Germplasm Conserved at the ICRISAT Genebank. 194 provinces in 21 countries? That’s a lot of gaps.
- Realizing access and benefit sharing from use of genetic resources between diverging international regimes: the scope for leadership. As supplied by Norway, that is.
- Classification of seed storage behaviour of 67 Amazonian tree species. 1000-seed weight and seed moisture content at shedding are good, together, at predicting seed storage behaviour.
- Genetic Diversity and Population Structure in a Legacy Collection of Spring Barley Landraces Adapted to a Wide Range of Climates. 10 climatic clusters.
- Assessment of genetic variation within a global collection of lentil (Lens culinaris Medik.) cultivars and landraces using SNP markers. Geographic pattern for commercial varieties, but not for landraces.
- Omne Ignotum pro Magnifico: characterization of commercial Bilberry extracts to fight adulteration. That would be Vaccinium myrtillus. You need to keep a sharp eye on the whole production process.
- The Contribution of the Solanaceae Coordinated Agricultural Project to Potato Breeding. It boils down to the Infinium 8303 Potato SNP Array, and it’s contribution to potato breeding has apparently been important.
- Horses as Sources of Proprietary Information: Commercialization, Conservation, and Compensation Pursuant to the Convention on Biological Diversity. You need a value chain with “a sequence of proprietary rights agreements governed and regulated by both tangible and intangible property regimes.” Well, yeah.
Brainfood: Safflower diversity, Afghan wheat diversity, Cassava diversity, SP drought tolerance, Olive diversity, Community genebanks, Organic yield meta-analysis, On farm success, Standardizing phenotyping, Wild collecting
- Assessment of Genetic Diversity and Population Structure in a Global Reference Collection of 531 Accessions of Carthamus tinctorius L. (Safflower) Using AFLP Markers. Bayesian analysis of genetic diversity of global (43 countries) collection held in India reveals 19 geographic groups, with most diversity in the Near East and Iran–Afghanistan regions.
- Molecular evaluation of orphan Afghan common wheat (Triticum aestivum L.) landraces collected by Dr. Kihara using single nucleotide polymorphic markers. Analysis (Bayesian, natch) of genetic diversity of over 400 wheat landraces collected 1950-1970 and conserved at the Kihara Institute for Biological Research, Japan reveals agroecological patterning and hotspot in Badakhshan province.
- Sources of pest resistance in cassava. Analysis of 89 trials over 25 years involving the CIAT cassava collection identifies 129 landraces with high resistance to thrips, 33 to green mites and 19 to whiteflies.
- Screening sweetpotato genotypes for tolerance to drought stress. Days to permanent wilting point (DPWP) points to 8 promising clones in Kenya.
- Olive domestication and diversification in the Mediterranean Basin. About 400 wild and cultivated accessions divide up into W, central and E groups and show evidence of admixture among them and local domestication events.
- The Multiple Functions and Services of Community Seedbanks. More than just conservation.
- Diversification practices reduce organic to conventional yield gap. More data and fancier maths finds a lower organic yield gap (20%), which is halved by multi-cropping and crop rotations.
- Conserving landraces and improving livelihoods: how to assess the success of on farm conservation projects? All you need is two graphs.
- Finding Our Way through Phenotypes. “We urge all biologists, data managers, and clinicians to actively support the development, evaluation, refinement, and adoption of methodologies, tools, syntaxes, and standards for capturing and computing over phenotypic data and to collaborate in bringing about a coordinated approach.” Amen.
- Wild food in Europe: A synthesis of knowledge and data of terrestrial wild food as an ecosystem service. 65 million people collect, and at least 100 million consume, wild food. But only 81 plants? Thought it would be more. But even so, quite an ecosystem service.
All maize, all the time
Lots on maize on the interwebs lately. First, there was a Nature Plants paper on the origin of the crop in the southwestern US, comparing DNA from ancient cobs with that from Mexican landraces:
“When considered together, the results suggest that the maize of the U.S. Southwest had a complex origin, first entering the U.S. via a highland route about 4,100 years ago and later via a lowland coastal route about 2,000 years ago,” said Jeffrey Ross-Ibarra, an associate professor in the Department of Plant Sciences.
A separate article in the journal summarized the results and set them in a wider context:
As genomic and palaeo-genomic studies have become more common, it has become increasingly clear that virtually every domestic plant and animal has incorporated genomes of numerous populations, including many that were not involved in the original domestication process. For example, although grapes, apples and pigs were domesticated outside of Europe, admixture with native wild European species has been so significant as to obscure the geographic origins of the modern domestic populations.
Meanwhile, the controversy over how to measure genetic erosion in maize continues, though I’m afraid in this case only the extract is free.
Which all means that the rather nice learning resource on maize domestication at the University of Utah, which I coincidentally recently came across, may need to be tweaked a bit.
Incidentally, if you plug Zea into the Native American Ethnobotany database at the University of Michigan, also a serendipitous find over the holidays, you’ll see that maize was far from being just a food plant.
There are even a couple of historical maize specimens included in the beta version of the new data portal of the Natural History Museum in London, which seems to be getting the softest of launches just now. Great to browse through. Not sure what kind of launch Brazil’s new(ish) biodiversity information system (SiBBs) got, but it too features maize records, over 400 in this case, though only 10 georeferenced. The source of most is given as “Dados repatriados – United States (no coordinates)”, which means that they came from GBIF, and in the case of maize are probably therefore mostly from GRIN. As I said a couple of posts ago for wheat, data sure does get around online.