kawuli (kawuli) wrote,
kawuli
kawuli

The Green Revolution

Posted in full at: http://ift.tt/2a81qaU at July 26, 2016 at 08:33AM
Today in Mo Talks About Agriculture: What is the Green Revolution? Is it the best thing ever and responsible for Saving the World? Is it a power grab by Evil Corporations to screw over farmers? Or, perhaps, is it a complex issue that has both good and bad attributes?



If you know me at all, you can tell I’m going to claim the third option.

What we call the Green Revolution started in about the 1960s, when scientists at the Centro de Mejoramiento de Mais y Trigo (Center for Maize and Wheat Improvement, CIMMYT), in Mexico, and the International Rice Research Institute (IRRI), in the Phillipines, developed dwarf hybrids of wheat and rice respectively. The most famous person associated with this is Norman Borlaug, who was from the US and developed the wheat hybrids at CIMMYT, and later won the Nobel Peace Prize for helping India avoid what was then considered an inevitable famine.

Before we go any further, I am going to clarify the word “hybrid” because somehow it’s gotten a bad rap that it doesn’t really deserve. A hybrid is a seed that comes from crossing two “inbred lines”–which are genetically uniform varieties that have been developed by crossing a plant with its close relatives (or itself, a trick only plants can do) over and over. Hybrids have a male and a female parent, just like people (don’t get political on me here this is the biology part). This is easiest to understand (and to do) in maize (corn for Americans). Maize has a male part–the tassel–and a female part–the silks. The pollen from the tassel gets blown onto the silks and together they create the maize embryo AKA seed. If you eat corn on the cob and find undeveloped grains (usually up at the top), those are the ones that didn’t get pollinated.


(Above: Maize in the field. Below: Maize plant diagram showing male and female parts)

Okay so for maize it’s easy: you have a male parent, which provides the pollen, and a female parent. You detassel the female parent so that the silks are fertilized only by the male parent. If you grew up somewhere where they produce seed corn, you may have worked detasseling, although now sometimes they do it by machine.

Other hybrids work basically the same way, except since in wheat, rice, sorghum, etc. the male and female parts are right next to each other, you have to play some games in order to ensure that the female parent doesn’t pollinate itself, like develop a female parent that doesn’t produce pollen (male-sterile).

See? Not evil, just biology. The reason people go to all this trouble is that the offspring of the two different parents has “hybrid vigor”– a.k.a. higher yield. In the case of the Green Revolution, the hybrids were also shorter–“dwarfs.” This meant that since the plant didn’t have to put so much energy into building a long stalk, it could put more into seeds. In addition, they were short and sturdy and so they didn’t fall over if they got too big (they “resist lodging”).

That meant you could put more fertilizer on these varieties and expect them to stay upright. I am not going to go into fertilizer and how it works here, but suffice it to say that for grains (maize, wheat, rice, etc) more nitrogen means more green stuff and more grain. If you put a lot of nitrogen on a local variety, it’ll get tall, produce more grain–and then fall over, because it’s too tall and spindly to support the weight of the grain.

Fantastic! Everyone should plant hybrids everywhere and put fertilizer on them and we can FEED THE WORLD!

Woah, calm down there, Monsanto.

First of all, and this is what most anti-hybrid people don’t like, you can’t really save hybrid seed from one year to the next. Because it’s made in that fancy way with a male and female parent, if you save the seed from your hybrid crop, it won’t be genetically the same as the seed you planted to get that crop. The grain is the result of a bunch of different crosses,with itself and any other varieties that are around. So if you plant that grain, it will grow to be all different heights and all different yields and you won’t get the hybrid vigor you got the first time. So you have to buy the seed again–and this is where it becomes important who produces the seed and who owns the intellectual property. Pioneer and Monsanto and all the rest own a lot of hybrid maize–even before they added specific genes through genetic modification. On the other hand, I worked with some sorghum breeders in Mali who’d developed sorghum hybrids and were working with farmer cooperatives to produce hybrid seed for sale. The intellectual property is a public good, available to anyone who wants to produce it. Big difference!

Second, hybrids are a little bit finnicky. If you graph environmental conditions (say, rainfall) vs. yield, you’d get a graph that looks something like this:



So there’s a fairly narrow range where a given hybrid does a lot better than a local variety, and out on the margins (too wet or too dry) the local does better. Also true of, say, soil fertility (although you wouldn’t get the right half of the graph). Also true–and this is important–for fertilizer rate. Most hybrids don’t outperform local varieties by much without fertilizer (the sorghum hybrids I was talking about earlier are a possible exception).

Now, all due respect to the organic agriculture people, but I don’t think it’s possible for all 7 billion people in the world to feed themselves without synthetic fertilizer. In any event it’d be very very hard. So I don’t see a problem, biologically, with applying fertilizer to get those hybrid benefits. However, not everyone can afford fertilizer, especially without access to credit to pay for it. Even in the US and the EU, if farmers couldn’t get loans, they would be completely screwed.

So, to get back to the Green Revolution, which was after all supposed to be the point of this post, we have these new hybrids, which are introduced in a package with fertilizer and, often, irrigation. In some places they work really well! India exported wheat! There was no giant famine! There’s a lot of farmers now who have invested in irrigation pumps and small tractors and have made a lot of money producing a lot of food. This is good.

But. Because using this package required money, required credit, required using resources differently, a) relatively few people (usually the ones who were already richer and had more land) benefited and b) damage has been done to the environment. Some small farmers went into huge amounts of debt paying for inputs they were told they had to have, and some of them have committed suicide because of it. The water table in some parts of India has dropped faster than the Ogallala aquifer (in the Western US, google it if you want to be worried about the future of US agriculture). Some people apply more nitrogen than plants can take up, and that nitrogen gets into the groundwater and poisons people. Not to mention the increasing use of pesticides that do the same. This is not an inevitable consequence of the technology. The EU especially is pretty good at enacting policies that enable farmers to use the best technology available, to regulate the use of chemicals so they cause less damage to the environment, and produce cheap food for people. (They do some damage to farmers in the Global South by exporting cheap subsidized milk powder among other things, but nobody’s perfect).

So really, the thing about the Green Revolution is that it developed some really useful technology, but then failed to deal with the institutional, social, cultural, economic, and environmental consequences of that technology. The further I get in studying science, the more I realize that technology is almost always the easiest part of any given system. It’s the people that are hard.

So the Green Revolution was great for some people, terrible for others, irrelevant for many–including most of Africa, which tends to fall outside of that window where hybrids are useful. There’s now a push for “A Green Revolution for Africa” (actually a thing, AGRA), which seems to be set on making exactly the same oversights that the first Green Revolution made: focusing too much on silver-bullet technologies and not on what in my research group we call “fitting options to context.” By which we mean looking at the environment, both ecological and social, and finding ways to develop technologies that fit into that environment (or change the environment, in some cases, by recommending policy things). That can only be done by working closely with farmers who would actually use the technologies, listening to what their priorities and constraints are, and that’s why we do participatory research. Anyway, all that is part of the framing of the paper I am working on, and a post for another day.

*Obligatory disclaimer: This is a tumblr post I wrote in under an hour, not a peer-reviewed scientific paper. I may be wrong on minor details. If you are interested, I can provide background reading on the history of the Green Revolution, how hybrids work, etc. but maybe google things first

Tags:mo talks about agriculture, muffins is an enabler, eatingmuffinsinanagitatedmanner, mo rambles, agriculture, my job, green revolution, crosspost

(Tumblr crosspost)
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