The Promise of High Protein Corn
The typical diet in the Sierra Madre consists of about 90% corn, in the form of tortillas, for corn is one of the few basic crops that grows well. The growing season is limited to the summer monsoons, which are torrential. Crops grown at other times must be irrigated, and in the steep barrancas, streamside plots which can be irrigated by gravity flow are very limited. Unfortunately, also, the alluvial flats by the river near Ajoya where irrigation by pumps would be economically feasible, are held by the wealthy land barons who prosper through share cropping and have little incentive for higher yield. Most planting is done by the slash and burn method on steep slopes, where profuse leaching during torrential summer rains makes for nitrogen-poor soil. Within one season after land is cleared, erosion makes the soil virtually useless until wild vegetation has slowly reestablished new topsoil. I have grown a variety of vegetables, experimentally, mostly with discouraging results. Many did poorly because of soil, others, such as giant pumpkins, grew robustly, only to rot before producing because of excessive rain. Other crops, such as sesame, mangoes and oranges near water courses grow well, but are in constant danger of invasion by leaf-cutting ants. Leaf-cutting ants make it impossible to grow wheat below 6000 feet, yet the leafcutters do not touch corn.
Corn, after all, is a native American plant as suited to living with leaf-cutting ants as the Indians are suited to corn. In many ways corn is the ideal crop. Even if another more nutritious crop were found to grow as well, the villagers would be slow to change their taste and planting habits. Unfortunately corn lacks certain factors needed for adequate human nutrition. It is deficient in niacin, hence the high incidence of pellagra in the world’s corn belt. While corn has most of the essential amino acids, it is low in lysine and tryptophane, so that protein deficiency is common with a high corn diet. We have treated hundreds of children for severe protein deficiency. It is of interest to note, however, that we have seen fewer cases of marked malnutrition in the darker skinned, more pure blooded Indians than in fairer individuals of more obviously Spanish extraction. The predominantly Indian families, even when dirt poor and surviving on tortillas with chilies and salt, are often surprisingly hardy, the mothers producing ample milk and their children roly-poly. By contrast, impoverished Spanish mothers tend to go dry early. Their children, weaned on corn meal and water are often sadly malnourished. It is conceivable that the Indians, through a longer history on a high corn diet, have better adapted to it.
A significant breakthrough on the problem of protein deficiency with high corn diet has recently been made by agronomists at Cornell University, who developed a hybrid corn called Opaque-2. This new corn, high in both lysine and tryptophane, supplies all the essential amino acids for human nutrition. Keith McFarland of Los Altos, California, secured four varieties of Opaque-2 for experimental planting in the barrancas. Dr. Donald Aitkin of La Honda, California, obtained for Project Piaxtla, a grant of $100 from the John Muir Institute for Environmental Studies, to conduct the planting experiment. At present, we have thirty experimental plots, some planted by plow and some with planting stick, in varying terrain from 1000 to 5500 feet in elevation. It is still too early to know the final results, but most of the corn is growing well and already producing ears. If Opaque-2 succeeds in the barrancas, it will make a tremendous difference in the nutritional level of the people.