In the forage genebank on the Addis Ababa campus of the International Livestock Research Institute (ILRI), Cary Fowler, executive director of the Global Crop Diversity Trust (left), and Jean Hanson (middle), a geneticist who headed ILRI forage diversity work for two decades and now consults for ILRI, and a member of ILRI’s forage diversity team examine specially designed bags that will store duplicate forage seed that ILRI sent for permanent storage in the Svalbard Seed Vault located in the Norwegian Arctic Circle (photo credit: ILRI/Mann).

Cary Fowler, executive director of the Global Crop Diversity Trust, has published another well-articulated and eminently sensible argument in his Crop Diversity Topics e-newsletter on the wisdom on not ‘betting the farm’ on any one crop or one strategy.

Fowler argues for combining strategies for conserving human food and livestock forage plants both in laboratories (ex situ) and on farms (in situ). Here he talks about the diversity of our food and feed crops. Much of his advice, however, is also applicable to strategies for conserving the diversity of the world’s livestock breeds.

‘. . . [A]gro-conservationists of all stripes continue to squabble amongst themselves over how to conserve. Should the diversity of our agricultural crops be conserved ex-situ in genebanks or in-situ on farms and in natural habitats?

‘A majority employs the word “or”. It seems only a less vocal minority can imagine and actually promote a different formulation: ex-situ and in-situ. . . .

‘No single strategy for conserving crop diversity is perfect or fool-proof. Something can always go wrong. As an organization, the Global Crop Diversity Trust is constitutionally focused on ex-situ conservation. It supports genebank collections. It believes that this approach to conservation has great merit. Rigorous protocols can be established. Research on the diversity is facilitated. And those needing the diversity—for plant breeding, for example—can locate and acquire it easily, across borders, and according to recognized norms. . . .

‘[But] the conservation of crop diversity on farms and in protected areas (for crop wild relatives) also deserves support. . . .

‘Promoting in-situ conservation as an exclusive strategy has instant and visceral appeal to many well-meaning people. It seems natural. It keeps the plants outside where at least theoretically they can continue to evolve. It involves farmers, not big institutions. What’s not to like about it?

‘Conservation in-situ allows for continual evolution, a definite plus. But, if we promote this kind of conservation exclusively, we have to accept that even as farmers promote continued and beneficial adaptation, they can inadvertently select against and eliminate other diversity in the varieties under their care—including traits that might someday be worthwhile. As a way of promoting evolution, the in-situ approach excels; as a method for conserving what already exists, it has shortcomings.

‘Most in-situ conservation is secondary to production. Farms are not museums. If a farmer is conserving a unique crop variety, it is usually because he/she wants to eat or sell it in the future. This, of course is hardly a completely reliable situation. The farmer might die or move to the city. Newer, higher yielding varieties can come along and in the blink of an eye the farmer can decide to replace the old with the new. We call this “genetic erosion.” The phenomenon is well documented and on-going. Genebanks are full of samples of varieties abandoned by farmers—varieties the in-situ “system” no longer conserves.

‘Finally, we turn to the purpose of conservation of crop diversity, which is not conservation but use. . . .

‘Many farmers—typically the poorest—are not adequately served by modern plant breeding programs whether public or private. Such farmers often scrape by on small plots of infertile land with low-yielding varieties. In many cases, they are growing crops for which there are few or even no trained plant breeders. That’s life for a subsistence farmer in many developing countries.

‘How will these farmers—and their crops—meet the challenge of climate change? As it stands now, I’m not sure they will. Where will their climate-ready varieties come from? At the moment, no one seems to be offering a credible solution. A tragedy of epic proportions is thus unfolding.

‘One possible response, I believe, lies in uniting in-situ and ex-situ advocates in a common cause. Let’s bring together the scientific and genetic resources of genebanks with the local knowledge and outreach of national programs and NGOs. This could provide new diversity to large numbers of farmers, empowering them to ratchet up their own indigenous selection and plant breeding efforts.

‘Who knows, such a joint effort might even encourage enthusiasts of the two complementary conservation strategies to become more complimentary towards each other. . . .’

Read the whole article at Crop Diversity Topics: No. 26–Betting the farm, 2011.