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Blogging the big birthday: One man’s selection

As the entire thinking world prepares to celebrate the 200th anniversary of the birth of Charles Darwin, tomorrow, lots of people (ourselves including) are unable to contain themselves. One of those is R. Ford Denison, who shares a selection of Darwin quotes that he was preparing to take to a celebratory dinner. A great selection it is too, revealing Denison’s own status as a man who takes evolution in agriculture very seriously. I wouldn’t say that this was my own favourite, but it is one that I had not noted before:

Look at a plant in the midst of its range, why does it not double or quadruple its numbers? We know it can perfectly well withstand a little more heat or cold, dampness or dryness, for elsewhere it ranges into slightly hotter or colder, damper or drier districts. In this case we can clearly see that if we wish in imagination to give the plant the power of increasing in number, we should have to give it some advantage over its competitors, or over the animals which prey on it.

There’s more where that came from.

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Agrobiodiversity everywhere, if you look

My weekend reading included two pieces that I felt sure would prove well written and engaging, but which I frankly did not think would yield much in the way of agrobiodiversity fodder. Turns out I was wrong, at least on the latter point.

Felipe Fernandez-Armesto’s review of the Encyclopedia of Exploration 1850 to 1940 by Raymond John Howgego is indeed a model of its type: informative, stimulating and charming. It also includes a reference to the late nineteenth-century Swiss ethnobotanist of Paraguay Moisés Bertoni, who described Stevia rebaudiana, a controversial sugar substitute. And another to the Société Impériale Zoologique d’Acclimatation, which had a famous birthday boy as a loyal member in its early days. ((It’s now the Société nationale de protection de la nature.)) A Colonel Henry Wayne apparently won the society’s gold medal for his efforts to introduce camels to the US.

The second piece that intrigued me over the weekend was an article by Matt Jenkins in the Smithsonian Magazine about the elite pilots who guide ships through the treacherous, sand-barred mouth of the Columbia River in Oregon. What’s the agrobiodiversity angle? Well, Portland and other upriver ports are the the main gateway in the US for its wheat and barley exports. The river pilots can shut down the entrance to the river if conditions are too bad, but, to quote one of them:

“When we shut down the bar for two days, trains are backed up all the way into the Midwest. And just like a traffic jam on the freeway, once you clear the wreck, it takes a long time for it to smooth out again.”

It’s a great image. The world’s interdependence for agricultural products ((And coincidentally I came across a great graphical representation of that yesterday, thanks to blogging machine Tom Barnett.)) resting on the judgement of a dozen or so salty sea dogs in the Pacific Northwest.

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Maize aguafiestas

From Jacob van Etten.

Uncorking a big bottle of agrobiodiversity, that is what Mexico’s first farmers did when they domesticated maize. Not only is maize enormously malleable, genetic diversity also goes everywhere through cross-pollination. That is in traditional farming systems. Modern maize improvement has been about sorting out this abundance by “freezing” it into breeding lines, to get some control over the diversity feast. But what happens when the hybrids are released into the dance room again?

An Italian study just out quantifies the gene flow from hybrids to traditional varieties. It finds different degrees of purity in the traditional varieties, but no genetic erosion. This is an interesting finding in the light of writings about “creolisation” in Mesoamerican agriculture. Creolisation, the mixing of modern and traditional varieties, is thought to lead to plants that combine their benefits. I have always wondered if the creolised varieties of Mesoamerica are not modern varieties “creolised” by selection instead of mixing with traditional varieties. Something similar to the Italian study would be needed to find this out.

The question is only one step removed from the issue of gene flow from transgenic crops to traditional varieties. Perhaps you remember the Quist and Chapela paper published in Nature in 2001 on the presence of transgenes in Mexican traditional maize, and the controversy it generated. A new study confirms the presence of transgenes in Mexico with an improved study design. Through genetic population simulations it also explains why detection of transgenes is erratic and prone to giving false negatives. The distribution of the transgenes is likely to be very skewed. A few fields will have much of them, but most will have very few. This has to be taken into account and therefore authors call for more rigorous sampling methods to detect transgene presence.

There is little discussion or speculation about the effects of transgenes on maize diversity. Will the transgenes just add to the existing diversity, like the hybrids in Italy? Will they perhaps produce some benefits, like the creolized varieties? Or will, in some Monty Python-like scenario, the big seed companies pick up the message about rigorous sampling and start to trace transgenes in Mexico in order to charge farmers for unlicensed use of their technology?

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Is all climate change bad?

Julián Ramírez-Villegas commented on the 4th World Congress on Conservation Agriculture, which we nibbled last week. We’re elevating his comment to a guest post.

I was on that conference last week (the conservation agriculture one). Surprisingly, all people there are completely [certain] that climate change is completely bad (and that there are no chances of survival for our agricultural systems while we don’t switch to conservation agriculture). They always point [out] the bad side of each issue (i.e. they say: more rainfall means flooding and less rainfall means more water consumption) and put that as an universal truth, which is not very scientific I guess, but you judge.

They also have these global-averages indicating that population is growing up to a number we won’t be able to feed in 2050, that water resources are to decline worldwide, that yields are completely falling down, and that soil is about to lose its most important fertility properties. But I wasn’t able to find any specific case where all those things could happen at the same time. However, at the end of each presentation you find the phrase “more resources for R & D”, which from my side looks a bit suspicious.

Say, I’m not sure about what could happen up to 2050, but we have these GC models saying that impacts vary according to different areas. And I wonder if one could try to change all agricultural systems in the world (one by one) using such global averages and coarse statistics.

And a very quick question: “how would one expand/intensify a conservation agriculture system, if it is supposed to be used in smallholdings, which owners don’t have either the land or the financial support to expand/intensify their systems?”