- Archaeological expansions in tropical South America during the late Holocene: Assessing the role of demic diffusion. Some agricultural diffusion in lowland South America was the movement of ideas rather than people.
- The origins of Amazonian landscapes: Plant cultivation, domestication and the spread of food production in tropical South America. Where did the farming people and/or ideas move from? The sub-Andean montane forest of NW South America and the shrub savannahs and seasonal forests of SW Amazonia.
- Genetic Diversity, Nitrogen Fixation, and Water Use Efficiency in a Panel of Honduran Common Bean (Phaseolus vulgaris L.) Landraces and Modern Genotypes. Landraces showed better N fixation, but lower yields, than modern varieties.
- Maize genotypes with deep root systems tolerate salt stress better than those with shallow root systems during early growth. Ok, but? There’s always a but.
- Challenges for Ex Situ Conservation of Wild Bananas: Seeds Collected in Papua New Guinea Have Variable Levels of Desiccation Tolerance. Avoid the basal end of the infructescence. Among other things.
- Detection of banana plants and their major diseases through aerial images and machine learning methods: A case study in DR Congo and Republic of Benin. Yeah but can you apply it to collecting the wild relatives?
- Genetic and genomic resources for finger millet improvement: opportunities for advancing climate-smart agriculture. No way this can be called neglected any longer. But is it still under-utilized?
- Genotyping-by-Sequencing to Unlock Genetic Diversity and Population Structure in White Yam (Dioscorea rotundata Poir.). More landrace variation within countries than among.
- BRIDGE – A Visual Analytics Web Tool for Barley Genebank Genomics. Do white yam next?
- Pedigree analysis of pre-breeding efforts in Trifolium spp. germplasm in New Zealand. Not a huge number of parents have been used, but reasonable diversity in most species.
- Pleistocene climate changes, and not agricultural spread, accounts for range expansion and admixture in the dominant grassland species Lolium perenne L. Lots more unused diversity out there. For now.
- IUCN Red List and the value of integrating genetics. Applying some genetic rules of thumb make some endangered species even more so.
- Variation in Seed Metabolites between Two Indica Rice Accessions Differing in Seed Longevity. Candidate biochemical indicators of impending seed death detected.
- Sustainability strategies by companies in the global coffee sector. They are close to non-existent.
- Camel Genetic Resources Conservation through Tourism: A Key Sociocultural Approach of Camelback Leisure Riding. Camel rides could be used for conservation, but they’ll have to deliver more than just conservation.
Brainfood: Dietary diversity, Farm diversity double, Neolithic dairy, Exotic breeds, Yam viruses, Cassava GWAS, Satellite phenotyping, Forest restoration & disturbance, Genetic rescue, Budwood cryo, SP cryo, Dry grasslands, Botanical gardens, Remote sensing
- Agricultural Food Production Diversity and Dietary Diversity among Female Small Holder Farmers in a Region of the Ecuadorian Andes Experiencing Nutrition Transition. Higher diversity of crops on family farms is only weakly associated with greater dietary diversity and lower household food insecurity among female caretakers. Better than nothing, though, right?
- Productive Capacity of Biodiversity: Crop Diversity and Permanent Grasslands in Northwestern France. Having a bigger percentage of permanent grassland on your French farm, or a greater diversity of crops, can increase cereal and milk yields. No word on diets.
- The influence of landscape composition and configuration on crop yield resilience. No effect on yield per se (see above), but proximity to semi-natural habitat does increase yield stability in UK farms.
- Living off the land: Terrestrial-based diet and dairying in the farming communities of the Neolithic Balkans. Ancient farmers had a varied diet, but possibly not involving consumption of raw milk, at least by adults.
- Food securers or invasive aliens? Trends and consequences of non-native livestock introgression in developing countries. In 40 countries, the proportion of livestock populations belonging to local breeds has been decreasing by about 1% a year for the past 20 years. Hey, but milk yield per cow has been going up, so there’s that.
- Potentials of Cultivated Varieties and Wild Yam Seeds as Efficient Alternative Plant Genetic Resources for Resistant Genotypes against Yam Mosaic Virus (YMV) in Togo. Work with seeds! But were they properly inoculated? Hopefully a virologist will tell us.
- Genome-wide association analysis reveals new insights into the genetic architecture of defensive, agro-morphological and quality-related traits in cassava. Lots of interesting markers for cassava breeders, or at least those working with material from W Africa. Do it for yams next?
- High-resolution satellite imagery applications in crop phenotyping: An overview. Clouds, you say? Not a problem any more. But can it distinguish landraces from modern varieties? What’s needed is a sort of mutant algorithm, I guess.
- Crop type identification and spatial mapping using Sentinel-2 satellite data with focus on field-level information. Still some way from being able to distinguish landraces from modern varieties, I see.
- Global forest restoration and the importance of prioritizing local communities. I’m shocked I tell you, shocked.
- Protection gaps and restoration opportunities for primary forests in Europe. A lot of restoration could usefully be done in currently protected areas, though it would be better if these were expanded. No word on local communities.
- Mapping the forest disturbance regimes of Europe. I guess this means that restoration, when it happens, will be monitored from space.
- Genetic rescue: A critique of the evidence supports maximizing genetic diversity rather than minimizing the introduction of putatively harmful genetic variation. When you do do restoration, don’t worry about genetic pollution, just go for as much diversity as possible. Well, for small relict populations. Of animals.
- Considerations for large-scale implementation of dormant budwood cryopreservation. It’s about the logistics.
- Development of a fast and user-friendly cryopreservation protocol for sweet potato genetic resources. It’s the axillary meristems. Among other things.
- The human–environment nexus and vegetation–rainfall sensitivity in tropical drylands. Dryland grasslands in Africa and Asia less able to respond to water availability overall, more able in Australia and S America, evens stevens in N America. Would be interesting to mash up particularly hard-hit areas with CWR and forage germplasm collecting localities.
- Botanic garden solutions to the plant extinction crisis. Expertise, tools, facilities, and networks are there. You know what’s missing, right?
Mapping crop species diversity in space and time
A big thank you to Fernando Aramburu Merlos, one of the authors of a very interesting recent paper on crop rotation in the USA, for contributing this nice blog post describing his findings.
If a picture is worth a thousand words, a good map is worth a million. Or, at least, that is how it felt after spending many hours staring at CropScape and mapping crop rotations – that is, the sequence in which different crop species are planted in a field – across the United States.
The USDA CropScape database is amazing: it identifies the crop planted for 30m grid cells across all the contiguous United States for the last 10+ years. It is a unique resource to better understand crop species diversity patterns for an entire, large country, and that is what we set out to do. “Let’s download the data and see what we can do,” said my advisor Robert Hijmans some time ago. But having a lot of data can also be overwhelming, and questions abounded. How should we estimate diversity? At what scale? And in what dimension: time or space, or both? In the end, much of the analysis focused on how temporal and spatial diversity are connected.
As an agronomist by training, it astonished me how little was available on spatial patterns in temporal diversity. For so many hours I have had to listen to lectures and read about the benefits of crop rotations, but I could not find a single crop rotation diversity map. One reason is surely that you need high spatial resolution crop distribution data for that, which is not available for most countries. So I was thrilled to create the first crop rotation diversity map for the US. I still can’t stop looking at it. Here it is.
The map, and the article that discussed it, has just been published. ((Aramburu Merlos, F., and R.J. Hijmans, 2020. The scale dependency of spatial crop species diversity and its relation to temporal diversity. Proceedings of the National Academy of Sciences. If you don’t have a subscription, it will become open access on April 2021. If you can’t wait, please, email me at faramburumerlos at ucdavis.edu and I’ll happily provide a copy.)) It shows (to no one’s surprise) that temporal crop species diversity in time is very low in most of the USA. The national average is 2.1 crops, with 86% of the cropland with 3 or fewer crops in rotation. We also found that the greater the popularity ((Meaning their planted area.)) of an annual crop, the less diverse is the rotation it is grown in. We proposed various reasons for that, but the take-home message is that “to increase crop species diversity, currently minor crops would have to increase in area at the expense of these major crops.” We would need less maize, soybeans and wheat to make space for other crops (to get back to the peak-diversity of the 1960s).
The scale issue was the hardest to tackle, and it is not just a purely academic concern. A number of recent papers use country level crop diversity data to explain food production stability and pollination . Our analysis suggest that while these country level analyses may be of interest, it is important to note that national level diversity is not directly related to farm level diversity, as many authors seem to assume.
So do read our paper if any of this interests you. And if it does not, you can still simply enjoy the maps.
Nibbles: Crop mapping, Sampling, Rice domestication, Coffee rust podcast, Wool dogs
- Crop-Climate Suitability Mapping. Yes, another one. I feel a proper post coming on.
- Tweet from Sean Hoban on ex situ sampling strategies. I feel a proper post coming on.
- Proper blog post explains a really complicated rice domestication paper in about a page.
- Proper podcast from Jeremy on, among other things, why coffee leaf rust is not why the Brits drink tea.
- Not sure if this is blog post, but it’s a really good example of weaving together (see what I did there?) different pieces of work on the wool dogs (sic) of the Pacific NW.
Brainfood: Sorghum lodging, GR wheat, Wild potato core, Wild tomato structure, Protected areas, Biodiversity agreements, Malt archaeology, Hittite archeology, Seed traders, Peasant networks, Seed storage, Mesoamerican crop origins, Intensification, Cattle breeds, Pig domestication, Rice barcodes, Potato history, Rice spread
- Large-scale genome-wide association study reveals that drought-induced lodging in grain sorghum is associated with plant height and traits linked to carbon remobilisation. To reduce lodging, better to select for stay-green (delayed leaf senescence) than for short stature and lodging resistance per se. Here’s a Twitter thread by one of the authors summarizing the findings.
- Green revolution ‘stumbles’ in a dry environment: Dwarf wheat with Rht genes fails to produce higher grain yield than taller plants under drought. At least it doesn’t lodge, though, right?
- A Core Subset of the ex situ Collection of S. demissum at the US Potato Genebank. From 149 to 38, keeping 96% of all marker diversity.
- Migration through a major Andean ecogeographic disruption as a driver of genotypic and phenotypic diversity in a wild tomato species. I guess if you were going to make a core collection for this you could do worse than sample ecogeographically diverse and isolated spots. Tricky to conserve in situ though.
- DNA barcoding of Oryza: conventional, specific, and super barcodes. 6 hypervariable regions in the chloroplast genome can serve as rice-specific DNA barcodes. Assuming you agree on species concepts in the first place.
- A “Global Safety Net” to reverse biodiversity loss and stabilize Earth’s climate. The 50% of the Earth to save to save the Earth.
- Three Key considerations for biodiversity conservation in multilateral agreements. Plan, model, assign responsibility.
- Mashes to Mashes, Crust to Crust. Presenting a novel microstructural marker for malting in the archaeological record. Aleurone cell breakdown in archaeobotanical remains is a robust indicator of beer-making. I bet they find it everywhere now.
- The agroecology of an early state: new results from Hattusha. Huge underground grain silos, with each container holding grain from multiple sites, which could be evidence of tax-paying. But no word on beer.
- Informal Seed Traders: The Backbone of Seed Business and African Smallholder Seed Supply. Lots of room for engagement, and considerable upside. If I were to pick out just one high-potential intervention, it would be providing training in seed testing.
- Restoring cultivated agrobiodiversity: The political ecology of knowledge networks between local peasant seed groups in France. I’m sure they’re testing their seeds.
- A Protective Role for Accumulated Dry Matter Reserves in Seeds During Desiccation: Implications for Conservation. Cells must have >35% dry matter to be able to withstand desiccation.
- Multiple lines of evidence for the origin of domesticated chili pepper, Capsicum annuum, in Mexico. It looks like we — inexplicably — missed this the first time around. Chilli, maize and beans originated in different parts of Mexico.
- Ecological intensification and diversification approaches to maintain biodiversity, ecosystem services and food production in a changing world. Though you can change one thing at a time, it’s better to redesign the whole system. But is the better the enemy of the good?
- Refining the genetic structure and relationships of European cattle breeds through meta-analysis of worldwide genomic SNP data, focusing on Italian cattle. 2 groups among Italian breeds: North-Central breeds linked to Alpine and Iberian breeds, and Podolian-Sicilian breeds with links to the Balkans.
- The Archaeology of Pig Domestication in Eurasia. Independent domestication in northern Mesopotamia by 7500 BC (extensive management) and China by 6000 BC (maybe intensive); failed to take off in Japan, for interesting reasons.
- Vegetative States: Potatoes, Affordances, and Survival Ecologies. The potato has both helped to underpin and resist state coercion. The Hittites would have worked something out, though, I feel.
- Holocene coastal evolution preceded the expansion of paddy field rice farming. Rice only moved south from the lower Yangtze 2-3000 years ago, once costal land opened up. No word on affordances.