Origins of the Maize
Maize is the domesticated variant of teosinte. The two plants have very dissimilar appearance, maize having a single tall stalk with multiple leaves and teosinte being a short, bushy plant. The difference between the two is largely controlled by differences in just two genes.
Several theories had been proposed about the specific origin of maize in Mesoamerica and the most accepted is that it comes from a direct domestication of a Mexican annual teosinte, Zea mays ssp. parviglumis, native to the Balsas River valley in south-eastern Mexico, with up to 12% of its genetic material obtained from Zea mays ssp. mexicana through introgression.
However, it is hard to understand why farmers were interested in the teosinte plant which such a small. But this is based on the aspect that at the plant today.
An American and British researchers team has just discovered that teosinte may be different in the climate conditions eleven thousand years ago. They cultivated teosinte plants in a greenhouse in which the temperature and the CO ₂ content were adjusted to those prevailing in Central America at the end of the Ice Age (40 % less CO ₂ in the atmosphere, warmer and drier). Result: teosinte grown in these conditions is very similar to the maize. Just a few years of cultivation were enough to demonstrate it.
Domestication
Maize crop landscape from Stéphanie’s house, Popocatepetl volcano, Puebla
The domestication of maize is of particular interest to researchers — archaeologists, geneticists, ethnobotanists, geographers, etc. The process is thought by some to have started 7,500 to 12,000 years ago. Research from the 1950s to 1970s originally focused on the hypothesis that maize domestication occurred in the highlands between the states of Oaxaca and Jalisco of Mexico, because the oldest archaeological remains of maize known at the time were found there. However, archaeobotanical studies published in 2009 point to the lowlands of the Balsas River valley, where stone milling tools with maize residue have been found in a 8,700-years old layer of deposits. Archaeological remains of early maize ears, found at Guila Naquitz Cave in the Oaxaca Valley, date back roughly 6,250 years; the oldest ears from caves near Tehuacan, Puebla (where I passed through!), date ca. 3,450 BC.
Most widely grown grain crop in the World
The Olmec and Mayans cultivated it in numerous varieties throughout Mesoamerica, cooked, ground or processed through nixtamalization. Beginning about 2500 BC, the crop spread through much of the Americas. The region developed a trade network based on surplus and varieties of maize crops. After European contact with the Americas in the late 15th and early 16th centuries, explorers and traders carried maize back to Europe and introduced it to other countries. Maize spread to the rest of the world because of its ability to grow in diverse climates.
Maize is the most widely grown grain crop throughout the Americas.
> Top five maize producers in 2012 (in tonnes)
United States 273,832,130
China 208,258,000
Brazil 71,296,478
Argentina 25,700,000
Mexico 22,069,254
World 690,668,292.
Mexico and more generally Mesoamerica is considered as the center of the Maize diversity
In the world, sugar-rich varieties called sweet corn are usually grown for human consumption directly as corn on the cob while field corn varieties are used for animal feed and as chemical feedstocks. But in Africa maize is as important for human food as in Mesoamerica.
As we could see, maize is central to Mexican food. Virtually every dish in Mexican cuisine uses maize. On form of grain or cornmeal, maize is the main ingredient of tortillas, tamales, pozole, atole and all the dishes based on them, like tacos, quesadillas, chilaquiles, enchiladas, tostadas and many more. In Mexico even a fungus of maize, known as huitlacoche is considered a delicacy (but not really to our taste).
Nowadays, new products like plastics, fabrics, adhesives, and many other chemical products from maize starch or bio-fuel are creating considerable new demands on maize crops.
Threats of Maize diversity
One of the major threats of maize diversity is the development genetically modified maize (GMO). As we could see, despite the moratorium of the Mexican government signed in 1998, several crop can be seen all along the route. We were astonished to see also in very remote areas, where the population is very poor and where it seems to be hard to buy GMO’s seeds every year for them.
Its neibourgh the US is the first maize producer in the world and 85% of the maize planted in there in 2009 are GMOs. As everybody knows, pollens do not know country borders and can fly easily and contaminate crops in the Mexican side, as it has already been reported in various occasion.
Other threats are more complex, about the intensification of agricultural techniques in rural areas where a high diversity is encountered. For example, while I was traveling through the Puebla and Oaxaca states of Mexico, I talked with farmers about their varieties. Many local varieties (of which « criollo » or creole varieties) do still exist but are disappearing because of social and agricultural changes.
Another threat that we want to point out is the progressive increase of wheat-based food in the Mexican diet, that replace little by little maize-based food. The typical example is the bread and pastries (like pan dulces) that we can find almost everywhere in Mexico. With the government support, programs are trying to promote the use of masa from nixtamalized maize and wheat, apparently to get a better nutritionally balanced food, as they say. As far as we know, Mexicans have never showed alimentary carency… Do you feel any lobby pressure in your diet from big companies like Bimbo, Sabritas, Gameta, etc?
Moreover, maize originally cultivated in the milpa agro-ecosystem, including at least corn, beans and squash plants, is disappearing as well for (apparently) more productive agro-systems. The milpa, through history, has been the site where the peasant, every year, has experienced, selected and domesticated plants, so that, along the time, was creating a pool of cultivated plants known as agrobiodiversity.
According to Genetic Resources Action International « only 20% of local maize varieties reported in Mexico in 1930 are still known. » And this could be a problem, not only for the agricultural/cultural heritage, but also for human health and economy, knowing that lack of genetic diversity can be linked to many of the major crop epidemics in human history…
Action for the Maize Diversity Preservation
Even is that sounds a very hard challenge, organizations and non-governmental organizations (NGO) are involved in the preservation of diversity of maize. We want to promote the work of some of them.
First, events are organized to foster interchange of maize seeds, like in Puebla and Oaxaca states. They are supporter by international organizations like Greenpeace and WWF.
COCIM (Consultora y Capacitación Integral Municipal, S. C.) en Oaxaca organizes events to promote the milpa, works with rural communities to rescue and promote it in the Oaxaca state, which still hosts a wide variety of native seeds adapted to all microclimates. It aims to assess, recover and enhance native seeds of the Milpa, seeking food security of families living presently in this area and for later generations.
GIRA in Michoacan aims to promote participatory processes of self-management, self-regulation and planning at local and regional levels, to research, develop and promote techniques and management systems based on the sustainable use of local resources, to generate and implement methodologies for diagnosis and evaluation of management systems, to serve as a training center, for documentation and dissemination and to influence policy-making.
Demonstration of tortilla making, Puebla
Milperos Autonomos : The collective organized the Maize harvesting Fair in Puebla, a great occasion to promote the tradition associated to the maize. I attended to this event, learnt how to make tortillas, how to nixtamalize the maize grain. I discovered all kind of handcrafts with grains and leaves of the maize, delighted the delicious home-made corn-based dishes and finally shared a good moment with a rock music concert in Nahuatl language. Amazing!
You can support them!!!
SUR LA ROUTE DU PATRIMOINE 