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Mashing maize seed systems and climate change

ResearchBlogging.org Smallholder farmers overwhelmingly save their own seed, maybe getting a bit extra from relatives, friends, neighbours and, very occasionally, further afield. If climate change is going to affect growing conditions — and it is — will the so-called informal sector be able to supply them with material that can thrive in the new conditions?

A new study suggests that, at least for smallholder maize farmers in eastern Mexico, getting seeds that will cope with climate change might not be too much of a problem. Mauricio Bellon of Bioversity 1, and his colleagues David Hodson of FAO and Jon Hellin at CIMMYT, wondered where Mexican maize farmers got their seed and how climate change might affect their environment. 2 So they asked farmers in 20 communities in four different agro-ecological zones: wet lowland, dry lowland, wet upper midaltitude, and highland.

Across all the zones, most of the seed lots are saved by the farmers from their own fields. Less than a third comes from off the farm, and most of that is from family, neighbours and friends. Very little comes from shops, government programmes, or strangers. But the system is by no means static. A quarter of the farmers said that they experimented with farmer landraces or modern varieties from further afield. Highland farmers are especially likely to experiment.

The rate of retention is low, however, particularly for improved varieties, suggesting that farmers know about improved varieties, have tested some of them, and have found them wanting.

Farmers get more than 90% of all seed lots within 10km of the community. The same goes for altitude. Almost all seed lots come from less than 50 metres higher or lower than the farm. The fact that farmers get their seed very locally, with little recourse to outside material, suggests that what they have locally is well adapted to local conditions. So how much will those conditions change?

Again, the scientists asked, not farmers but as many climate models as they could get their hands on. All the models predict that it will get dryer and hotter in the study areas. When the researchers looked in detail at how conditions in 1 km square “pixels” within the 10 km radius around the communities changed, they found that except in the highland communities, “the predicted future maize environments already are present within the 10-km radial zones and … the average distances to the predicted novel environments are relatively short”. Bottom line?

[F]armers should have relatively easy access to planting material adapted to the agro-ecological conditions predicted under climate-change scenarios.

In the highlands, however, things will not be so simple. Conditions for maize change most in the highlands, with more land becoming unsuitable and probably greater fragmentation of maize-growing areas. Traditional seed systems are unlikely to be able to provide the kinds of varieties farmers there will need, but those farmers also have a history of obtaining and experimenting with seed lots from further afield.

Researchers and extension workers should perhaps concentrate their efforts to help farmers prepare for climate change in those highland areas.

Having shown that the seed supply for one crop in one region is not as vulnerable to climate change as might have been expected, the big question is: how general might this be? Roughly half the highland maize grown in the developing world is outside Mexico. Farmers there will need to prepare too. And many other crops important to smallholder farmers are sourced through traditional, informal seed systems. As the authors note:

This approach, based on quantifying the spatial scope of traditional seed systems and relating these spatial scopes to potential climate shifts that would modify the distribution of growing environments and hence the fit between the germplasm to which farmers currently have access to and the one needed in the future, can be applied to different systems and circumstances, although the specifics probably will vary from one case to another.

How soon might those additional studies happen?

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Berry go Round part deux

Kate over at Beyond the Brambles put out an exuberant floristic Berry-go-round a few days ago. Her blog, her choices, although it did seem a little light on actual botany, to me. So once again I’m abusing a position of privilege to share some of the other submissions to July’s carnival. And if you would like to leave a submission for next month’s effort, hosted by Dave Coulter at Osage and Orange, well, just pop on over and fill in the submission form.

Speaking of Dave, he draws attention to a little known aspect of Detroit’s green renaissance. Sure, we’ve all heard about the urban ag and stuff, but he points to the birth of an amazing maze.

Mazes are stripes, and some plant leaves have stripes. On, then, to Part 2 of Joseph Tychonievich’s account of variegation at Greensparrow Gardens. I remember a great exhibit at Chelsea on variegation …

Greensparrows lead inexorably to rose gentians, of the square-stemmed sort. JSK has the lowdown on Sabatia angularis. And, for what they’re worth, Green Comet Milkweed (Asclepias viridiflora), thought to have been a victim of a nasty road accident, and Clasping Milkweed (Asclepias amplexicaulis). Herpetologists will recognize the specific epithet, but will they know what’s clasping what.

You want taxonomy? We’ve got taxonomy. And evolution. And links between the two. Joseph Craine at Wild Plants Post goes into the evolutionary history of the grasses and the forces that might have driven their adaptive radiation.

It’s all a question of niche exploitation. Or is it? Sarcozona goes all biblical on us as she attempts to untangle the knots surrounding invasive species. I’ve almost given up trying to control the ones that invade my terrace.

We’ve been a bit busy ourselves here at The Agricultural Biodiversity Weblog, hosting a guest post on the food that fed a thousand canoes and wondering whether Katherine of Aragon could possibly have been handing her pet a highly appropriate monkeynut (Arachis hypogaea)? The jury is still out.

And finally, a salute to the man without whom … Daniel does Gregor, and so did Google.

Have fun.

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Brainfood: Barley genes, Stability & Diversity, Access & Benefit Sharing,

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Onions evaluated “for food security”

Scientists at Warwick University’s Crop Centre have examined “96 of the world’s onion varieties” for resistance to basal rot (caused by the ubiquitous Fusarium oxysporum) and their ability to form close relationships with certain beneficial fungi. The press release doesn’t go into any detail, such as which varieties top the lists, or anything useful like that, although it does raise some questions. Like, where were the onions from? Andrew Taylor, the researcher in charge, said this:

“We have developed a unique onion diversity set from material sourced from across the globe. We now have a extremely useful library of the variation in traits … all of which will be extremely useful to growers and seed producers dealing with changing conditions and threats to onion crops.”

Spiffy. And a nice alternative, eventually, to current control methods. But what exactly is this “unique onion diversity set”. Is it, by any chance, anything to do with the Allium collection maintained at the old UK National Vegetable Collection at Wellesbourne, recently threatened with closure? And if so, why wouldn’t that have been mentioned by the Warwick Crop Centre, which absorbed Wellesbourne and its Genetic Resources Unit? Surely anything good that comes out of the Wellesbourne genebank is an argument for continued support.

On a purely personal note, I’d love to know whether two varieties, Up-to-date and Bedfordshire Champion, were among the 96 that were evaluated. That’s because in 1948 the UK Ministry of Agriculture Fisheries and Food noted that Up-to-date had excellent resistance to white rot, while Bedfordshire Champion was highly susceptible. In the mid 1960s, MAFF decided they were the same variety, under synonyms, and dropped Up-to-date from the National Catalogue.Wellesbourne did maintain it, and it would be interesting to know whether the two had different profiles in this latest round of evaluation.

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Famine and diversity

The famine unfolding in Africa is rightly dominating news and comment around the world, the more since it is now “official”. One recurrent theme is that the disaster could have been, and was, foretold … and ignored. Jeffrey Sachs says he warned the US President.

[T]wo years ago, in a meeting with US President Barack Obama, I described the vulnerability of the African drylands. When the rains fail there, wars begin. I showed Obama a map from my book Common Wealth, which depicts the overlap of dryland climates and conflict zones. I noted to him that the region urgently requires a development strategy, not a military approach.

Obama responded that the US Congress would not support a major development effort for the drylands. “Find me another 100 votes in Congress,” he said.

I shouldn’t think the votes are there now, either, but Sachs’ fourfold prescription remains at least partially valid. Whether this particular drought can be laid at the door of climate change is not relevant; climate change will make droughts (and floods) more severe an we need to deal realistically with the greenhouse gas emissions that are driving climate change. Fertility rates are high, but if history is anything to go by, they won’t come down until living conditions and prospects improve. The region is poor and so, as Sachs notes, shocks that other regions might shrug off push it towards calamity. And unstable politics exacerbate the other problems; food security is hard to achieve in a region without other forms of security.

The big question is what sort of development strategy would work best in the region. Sachs, naturally enough, favours something like the interventions going on in the Millennium Villages Project. None of those, however, seem to me to address the root problem, which is that the land is too dry and too unpredictable to support anything other than pastoralism, and that pastoralism is a victim as much of modern geopolitics as it is of climate change. I have no idea what to think when I read things like this:

The government [of Kenya] has announced plans to immediately put 10,000 hectares of land in the River Omo delta around Lake Turkana under irrigation to produce maize, sorghum, vegetables and fruits to ease the food crisis frequently experienced in the region.

Can that possibly be the right approach? It seems very unlikely. Meanwhile, I’ll keep an eye on the information being shared at ILRI’s newsy blog.