Science and technology changed agriculture profoundly in the 20th century. Today, much of the developed world’s agriculture is a large-scale enterprise: mechanized, computer-controlled and based on sophisticated use of chemistry and knowledge of plant and soil physiology.
The invention of chemical fertilizers early in the century and their increasing use, together with mechanization and the development of high-yielding grain varieties, propelled the growth of agricultural productivity in the developed world. The Green Revolution brought these benefits to less developed nations.
As a result, despite a tripling of the global population, we have so far evaded Malthus’ 1798 prediction that human population growth would inevitably outstrip our ability to produce food. Over the second half of the 20th century, the hungry of the Earth shrank from half of its 3 billion human inhabitants to less than a billion of the current 6.5 billion.
Twentieth-century plant breeders learned to accelerate genetic changes in plants with chemicals and radiation — a rather shotgun approach to the genetic improvement of plants. The introduction of molecular methods began the current agricultural revolution. The use of such techniques is referred to as genetic modification (GM), genetic engineering or biotechnology. GM crops that resist certain pests and tolerate herbicides have gained rapid acceptance in many countries.
According to the International Service for the Acquisition of Agri-biotech Applications (ISAAA), GM crop adoption is growing at double-digit rates, reaching 114.3 million hectares in 23 countries last year. Perhaps most importantly, 11 million of the 12 million GM farmers are resource-poor smallholders.
In the 12 years since their commercial introduction, insect-resistant GM crops have increased yields while significantly decreasing the use of toxic pesticides. Herbicide-tolerant plants have decreased herbicide use and encouraged the widespread adoption of no-till farming, markedly reducing topsoil loss and promoting soil fertility.
Despite dire predictions, no adverse effects of GM crops on health, biodiversity or the environment have been documented to date. The only unanticipated effects so far have been beneficial. Insect-resistant GM corn, for example, shows much lower levels of mycotoxin contamination than conventionally or organically grown corn because the plants are resistant to the insect larvae that bore holes through which fungi enter plants. No holes, no fungi, no mycotoxins.
GM techniques are widely accepted in medicine and food technology. What would we do today in the face of the growing worldwide diabetes epidemic without human insulin, now produced on a very large scale from human insulin genes expressed in microorganisms?
But the use of molecular techniques to improve crop plants continues to be rejected emphatically by many countries in Europe, by Japan and — most tragically — by many African countries.
Food and energy price shocks have pulled the world up short. The so-called “food crisis” this year was not really a crisis in the sense of a condition that can be resolved by the quick application of emergency measures. It has been developing for decades. And it is not likely to disappear soon, though food prices are moderating for the moment.