Category: History

Posted on

Data is not the destination

Mike Jackson’s account of the early molecular work at IRRI’s International Rice Genebank is a nice reminder that the idea of the “genomic genebank” (as he calls it) is not as new as it may sounds. In the 1990s, RAPD and AFLP markers were already being used to identify duplicates, reveal genetic structure and, more ambitiously, to predict which accessions might possess useful traits. It’s the continuation of the trajectory I traced in my recent post on descriptors: from names and human-scored traits to photographs, digital phenotypes, molecular markers and now genomic information, each adding a layer of information that makes the collection more searchable and usable. The question keeps shifting from “what do we have?” to “which of what we have might be useful?”

Jackson’s story is also a key piece of the argument I tried to make in another recent post: preserving options is only the beginning. More, and better, information makes options easier to discover, but discovering an option is not the same as exercising it. The harder question is what happens next: how do we turn knowledge about what’s in a collection into actual selection, testing, breeding, adoption and impact? Data can open the door to better use of genebank collections. It cannot walk through it for us.

And there is a danger here. As our information about genebank collections becomes ever more layered, richer and more precise, it can start to look as though we’re solving the problem of use. We are not. We are solving the problem of finding possibilities. That’s only one part of the journey. A genomic prediction is not a breeding line; a photograph is not a phenotype under farmers’ conditions. The distance between knowing an option exists and actually exercising it still has to be travelled. That is a social and institutional process as much as a biological and technological one, and it starts only when the search is over.

Posted on

When farming worlds collide

When we think about crops moving around the world — and we often do around here — the Columbian Exchange is the canonical example, and why not? The transatlantic movement of maize, potatoes, tomatoes, cassava, and chili peppers to Europe, Africa and Asia, and of wheat, sugar, coffee, and livestock to the Americas, was profoundly transformative. It reshaped global agriculture and diets more dramatically than any single event in human history after the Neolithic.

But similar, if maybe smaller-scale, “exchanges” happened long before 1492. The deep history of agriculture features several ancient “mixing bowls,” let’s call them, where traditions from different geographic origins met and interacted in fascinating ways. These are natural experiments in how new crops become part of diversified farming systems, and I think they can be especially useful in thinking about “opportunity crops.”

Usually, by opportunity crops we mean local or regional crops that were perhaps once more important, and then declined. Or, even if they were never very important, they could still do more, given the chance, whether for diets or incomes, or resilience: indigenous fruits and vegetables, forgotten grains, traditional tubers, you know the kind of thing. Their local resurgence is a crucial path to diversification, for sure. But those agricultural mixing bowls suggest that crops from the outside also have a role in enriching local farming.

Continue reading “When farming worlds collide”

Posted on

There are no opportunity crops

At least, not in any biological sense.

No plant is born an “opportunity crop.” It becomes one when somebody finds a way to make its particular combination of characteristics valuable, in a particular context.

That does not make the term useless. It can be a convenient way to describe crops whose potential seems underdeveloped, or whose qualities come to matter more under changing climates, diets and markets. But the phrase can also mislead. It can make opportunity sound like something that resides in a species or variety.

But consider the Georgia peach. Today, the US state of Georgia is almost synonymous with peaches, at least to Americans. But it was not always so. The fruit arrived in North America with the Spanish in the mid-1500s1, spreading rapidly through the Southeast from seed, almost weed-like. For generations, peaches were mostly a local resource, made into pies, fed to livestock or turned into brandy.

As William Thomas Okie recounts in a recent piece in Smithsonian Magazine, it took deliberate selection and breeding, better production practices, research, transport and access to distant markets to turn the peach into a commercial industry — and eventually the icon it is today.

The lesson is not that peaches are in any way special. It’s almost the opposite.

When we talk about “opportunity crops” in the Global South, we often seem to be looking for crops that already possess a particular combination of characteristics: nutritious, climate resilient, locally adapted, culturally valued and perhaps capable of generating income.
But why should opportunity be an intrinsic property of a crop?

All crops contain genetic variation. Some of that variation may become valuable because of a new breeding objective, a new processing technology, a change in consumer preferences, a new market or simply changing environmental conditions.

We cannot know all of those opportunities in advance. Nobody knew in advance that the peach presented an opportunity in the American South.

The Georgia peach story also reminds us that an opportunity is not necessarily an opportunity for all. That industry developed within a society shaped by slavery and racial inequality, and its commercial success depended on agricultural labourers who didn’t much share in the value they helped create. If a neglected African crop becomes commercially valuable, who controls the breeding, seed, processing and markets. Who gets paid?

This does not mean that every crop deserves the same investment. Resources are limited, and choices have to be made. But it does suggest that the most useful question may not be “Which crops are opportunity crops?” but rather “Where is there diversity from which new opportunities could be created?”

This is why we need genebanks. They preserve options, not predictions. A crop or variety that looks unremarkable today may contain a characteristic that becomes valuable tomorrow.

Perhaps, then, we should stop thinking of opportunity crops as a special category of crops, waiting to be discovered. The real opportunity lies in maintaining enough diversity across all crops to keep our options open for whatever the future may bring.

Posted on

Brainfood: The diverse lives and times of crop diversity

Posted on

Crops made, and remade

Two new studies of very different crops – banana and chrysanthemum, of all things – end up telling surprisingly similar, deliciously complicated stories. For these crops, domestication was not once and done, so to speak. They were both repeatedly remade as people moved them through landscapes containing new wild diversity.

In the banana study, the authors suggest that a partly domesticated Musa acuminata lineage from New Guinea was carried westwards through Southeast Asia, encountering and hybridizing again and again with different local wild bananas along the way. Each encounter added new genetic material to an already changing crop, helping produce the genomic mosaics found in mainland Southeast Asian bananas today.

The chrysanthemum study reveals a strikingly parallel history: cultivated plants originating in China were introduced to Japan, where they encountered local wild populations and acquired new genetic diversity, before later movements to Europe and further breeding reshaped the crop again.

The papers also show that an essentially similar process played out somewhat differently in the two crops. In banana, repeated hybridization appears to have been important in the building of the crop itself, as domesticated or partly domesticated plants became the starting material for successive encounters with wild Musa. In chrysanthemum, genomic analysis reveals a more complex network of relationships among multiple wild and cultivated groups, with C. indicum among the important ancestral contributors. In this genetic cauldron, hybridization and introgression repeatedly diversified an established cultivated genepool, contributing to traits such as flower form, colour and plant architecture.

Taken together, these papers challenge the familiar “funnel,” or bottleneck, image of domestication: a one-way downward slide from diverse wild relative to genetically narrow crop. Instead, they point to a more stop-start, two-way, non-linear, geographically contingent process, in which (semi-)cultivated plants continue to encounter, absorb and be reshaped by wild diversity.

In both banana and chrysanthemum — and probably many other cases — wild relatives have been more active, continuous participants in creating the diversity of the crops we know today than we sometimes give them credit for. Or I have given them credit for at any rate.

That argues for treating the wild genepool not simply as a reservoir from which to fish out useful genes one at a time. The historical evidence suggests that crops have benefited in the past from repeatedly absorbing larger chunks of wild genetic diversity, allowing selection to reconstruct useful combinations. Might it be worth trying to make that happen again? Is anyone out there doing pre-breeding explicitly with an eye to the past?