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Livestock genomes not enough

You may remember we nibbled a Science paper entitled Time to Tap Africa’s Livestock Genomes which got a lot of traction in the press a few weeks ago. It has also generated an interesting discussion at the DAD-Net forum, set off by the following contribution by Dr Ilse Köhler-Rollefson of the League for Pastoral Peoples and Endogenous Livestock Development, which she has kindly allowed us to reproduce here.

Congratulations on this article – it is certainly great to have these issues raised in a high profile scientific journal! However, after reading the summary about it presented in the BBC interview, I am a bit worried about the notion of the need to “tap Africa’s animal genetic resources” before they have become extinct. For one, they are already being “tapped” by African pastoralists — and have been tapped for hundreds or thousands of years — to enable survival in inhospitable areas. One crucial aspect of pastoralist livestock is the ability to walk for ever and thereby access and then ingest and metabolize vegetation that would otherwise be of no use to humans. Their contribution to food security is thus enormous. Unfortunately, to my knowledge, no scientific research has ever focused on “walkability.”

But what we urgently need to realise is that many of the wonderful characteristics of African and other pastoralist livestock are not a question of genetics, but of learned behaviour, as Saverio Kraetli has shown in his seminal studies of WoDaaBe cattle breeders in Niger. It is therefore a fallacy to believe that we can “fix” certain weaknesses of Western or high-performance breeds by introducing the genes of African livestock into them.

This does not make it less urgent to conserve pastoralist livestock, as food security for people in marginal areas remains a major concern. In their Biocultural Community Protocol, the Samburu have testified how replacement of the Red Massai sheep with Dorper has undermined their drought resistance.

African livestock breeds and their unique traits can only be conserved in living systems, using agroecosystem approaches as spelled out in one of the Strategic Priorities for Action of the Global Plan of Action for Animal Genetic Resources. Consequently we need enabling policies for livestock keepers, much more than additional research at the genome level — which would be unable to address complex traits such as walkability.

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From fiasco to food systems

A contribution from Jessica Fanzo of Bioversity International. Many thanks, Jess!

As of 2010, one billion people are hungry, and 129 and 195 million children under five years of age are underweight and stunted respectively, with 90% of these children living in just 36 countries. Vitamin A and zinc deficiency alone contribute to over half a million child deaths annually. How could things have gone so wrong? Why is hunger and poor nutrition increasing or at least stagnating in much of the developing world?

Much of this falls on the nutrition and development community themselves. Although the prevention and treatment interventions highly endorsed in the 2008 Lancet series on maternal and child undernutrition provided some consensus among the global nutrition community, not all are comfortable with the current interventions being put forth to scale, which are predominantly health- and clinic-based interventions. To add more complications, the “how” to implement interventions from country to country in the developing world remains elusive. But then the international nutrition community has always been contentious.

The latest debate is coming from Michael Latham’s recent paper in World Nutrition, which is rebuking an often regarded “life saving” and cost effective intervention of giving children ages 6 to 59 months of age two high doses of vitamin A. Pioneering work by colleagues such as Professors Alfred Sommer and Keith West demonstrated very effectively that vitamin A can save children’s lives and prevent vitamin A caused blindness. And it certainly does, particularly in places where vitamin A deficiency has wreaked havoc on the lives of children. And we know that there are pockets where vitamin A deficiency still does.

Latham reported that what was thought of as a stop gap or short-term approach in preventing vitamin A deficiency, became THE only recommended approach to treat such deficiencies. He contests the evidence that the supplements reduce child morbidity: they not only have little effect on mortality, but can have adverse effects on respiratory infections, he says. Latham argued that the International Vitamin A Consultative Group and UNICEF pushed for the “magic bullet” capsule approach, in collaboration with industry, with little regard for other approaches, including plant-based foods.

So the debate continues. What PREVENTATIVE approaches should be undertaken? Prevention and treatment-based interventions, such as vitamin A supplementation, form a necessary and important dimension of addressing immediate needs and undernutrition. But more durable reductions in hunger must be accompanied by strategies that enhance food and livelihood security, including food production-based approaches aimed to enhance food availability and diet quality through local production and agricultural biodiversity.

There are food-focused interventions that can be integrated into the agriculture investments (largely staple crop food production) that could improve diet diversity and quality of diets rich in vitamin A sources, directly impacting the nutritional status of children. Promotion and usage of diverse homegardens and intercropping of plant foods rich in carotene, such as leafy greens and fruits such as mango, papaya, bananas, and pumpkin, along with plant oils, can provide rich sources of vitamin A for family diets, especially for complementary foods for young children. Livestock and small animal rearing can provide rich sources of vitamin A even if consumed a few times during the week. Introduction of nutrient-rich foods such as orange-fleshed sweet potato have been shown to increase vitamin A intake and serum retinol concentrations in young children in east Africa.

However, there is more than one way to skin a mango. The food-focused interventions are as essential as the vitamin A supplements as stop gaps in areas with documented vitamin A deficiency. But we need to go further. Recent calls for greater attention to hunger and undernutrition highlight the importance of integrating technical, well-coordinated interventions with broader strategies that address underlying causes of food insecurity – incorporating perspectives from agriculture, health, water and sanitation, infrastructure, gender and education. We need to think beyond “interventions” and more about systems approaches – in particular, food systems. How can food be better grown to improve the quantity and quality of the diet and of livelihoods. Food systems involve not only the land itself, but also water, natural resources, the ecosystem as a whole, and of course food, but all tethered to together with gender equity, better education, and legal reform and land tenure. Long-term investments in ensuring food systems are protected, conserved, rebuilt or promoted will be critically important to making real progress in preventing vitamin A deficiency, undernutrition and hunger, and ultimately the big culprit of them all, poverty.

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Perennial grains gain credibility

ResearchBlogging.org It has been almost 10 days since the publication of Increased Food and Ecosystem Security via Perennial Grains in the Policy Forum of the journal Science. 1 Not long in the 10,000 year history of agriculture, agreed, but long enough to have had a bit more impact, which it deserves for two reasons. First, there’s the subject itself: perennial grains. Then, there’s where it appeared; Science is pretty mainstream on most things, and its willingness to publish 29 authors from 21 institutions must help to bring perennial grains in from the cold.

As ever, the article is behind a paywall, so a summary is in order. Jerry Glover, of the Land institute in Salinas, Kansas, and his co-authors make several points. Grain yields from major crops have doubled since the 1950s, but 1 in 7 people are malnourished. Populations continue to grow, and biofuels are competing with food production. The best croplands are not at risk of soil erosion or degradation, but those lands are only 12.6% of total land area. More than half the world’s population depends instead on marginal lands, which are capable of growing crops but which are at risk of degradation under annual crops. Global food security depends on annual production of cereals, legumes and oilseeds, but for a variety of reasons the production of these staples is unsustainable and fragile. Against this background, as the authors say:

Development of perennial versions of important grain crops could expand options.

They go on to list the benefits of perennial crops, which I won’t repeat here, and some of the past history of this exciting research area. One of the key arguments against perennial crops is that plants make a trade-off between storing resources to overwinter vegetatively and putting those resources into seeds that can survive adverse conditions. In other words, you can have deep roots etc. or big seeds, but not both. But even if true, perennial grains may still be a good idea, for two reasons.

First, high yield is not the only factor governing the use of specific crops. Wheat, for example, yields less than maize, but is grown on a larger area than maize because it will produce some yield under conditions where most maize will produce none.

[L]ower yield perennial crops could be options where higher yield annuals cannot reliably achieve full yields. In semiarid regions of sub-Saharan Africa, annual crops often use less than 30% of rainfall due to high rates of water draining below root zones, evaporation and runoff … Perennial crops can reduce … water losses and be grown on highly erodable sites. For example perennial types of pigeon peas, important food crops and sources of biologically fixed nitrogen, are grown on steep slopes in regions of Malawi, China, and India.

The second reason perennial crops may be a good idea even though yields remain lower at present is that by virtue of their deeper roots and longer-lived leaf canopy, they can convert more sunlight into biomass than even the most advanced, most pampered annual crops. Miscanthus (a grass heavily touted for biofuel production) for example, with no additional fertilizer, produces almost 60% more aboveground biomass than heavily-fertilized maize.

Glover and his co-authors point out that plant breeders need to combine many desirable traits in perennial grains, and that new technologies like genome screening and marker-assisted selection can speed the process. They also point out that this requires greater investment, calling for new and expanded breeding programmes, expanded research, better global coordination, agreed prioritiy-setting and capacity development and training. 2 They also identify the many ways in which perennial crops could contribute to what they call “domestic and international challenges,” pointing out that several US agencies ought to have an interest in promoting R&D into perennial grains.

And that, perhaps, is where the article’s real importance lies, and why I am a little surprised that it has not (yet?) generated more discussion. With governments increasingly talking about food security in a much broader context than mere calories and proteins, and given Science’s clout as an outlet for important ideas, one can but hope that somewhere serious-minded people are considering shifting just a tiny bit of the agricultural research budget into obviously attractive alternatives to seeds and feeds.