green revolution

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The development and use of high-yielding crops (HYVs) in conjunction with improved agricultural technology. New breeds of crops have been developed to increase yields two to four times, to shorten the time required for growth such that more than one crop a year can be produced, and to produce a plant which can withstand extremes of climate or disease. The use of Mexican wheat has doubled yields in the Punjab, and HYV rice has been used to such effect in the Philippines that imports are no longer necessary. The green revolution has had most impact in South and East Asia, and in South America, but has not been taken up to the same extent in sub-Saharan Africa.

There have been drawbacks, however. The grain may not be as palatable or as attractive in appearance as the grain it replaces, and it may use up more energy to process. Seeds have to be bought, as the hybrids are not self-fertile, and some varieties are less resistant to drought and disease. Heavy applications of expensive fertilizers and insecticides are required and these are often made from non-renewable resources.

Herbicides are required because the fertilizer stimulates weed growth as well as crop growth. The high yields and reliance on artificial fertilizers can lead to impoverished soils. Traditional rice exporters, like Burma, have seen the collapse of their markets. Increased yields mean that landowners can use their holdings more profitably and this often means that tenants are dispossessed. Copious, but strictly regulated, irrigation is required.

The green revolution has benefited the most prosperous farmers in the most prosperous areas but its price is too high for many of the peasants who need its help. To that extent, it has only been a partial success.

In the early 1960s developments in agricultural production, sponsored by international funding agencies, led to what came to be called the Green Revolution. These developments emphasized hybrid seeds, mechanization, and pest control as answers to the agricultural backwardness of the Third World. High-yielding varieties were promoted, as was the use of pesticides, and economies of scale of production, which could be successful only through mechanization of agriculture. This initiative did result in much better production figures across a range of countries. However, the Green Revolution has been criticized by environmentalists and others for resulting in environmental disasters in the countries where it was most effective. Mechanization of agriculture, where successful, led to changing work and social patterns, an exacerbation of class divisions in society, and the displacement of minority groups like tribal peoples and politically marginalized groups such as women from agricultural production. Further, new types of crops were not resistant to local diseases and required high levels of pesticides which polluted the local waterways, impoverished the land, and also increased the dependency of many Third World countries on the West with import of pesticides. Moreover, the commercialization of agriculture led to the exporting of food out of the local areas, increasing the dependence of producers on market forces that did not always benefit the majority of producers.

— Shirin Rai

The Green Revolution was the notable increase in cereal-grains production in Mexico, India, Pakistan, the Philippines, and other developing countries in the 1960s and 1970s. This trend resulted from the introduction of hybrid strains of wheat, rice, and corn (maize) and the adoption of modern agricultural technologies, including irrigation and heavy doses of chemical fertilizer. The Green Revolution was launched by research establishments in Mexico and the Philippines that were funded by the governments of those nations, international donor organizations, and the U.S. government. Similar work is still being carried out by a network of institutes around the world.

The Green Revolution was based on years of painstaking scientific research, but when it was deployed in the field, it yielded dramatic results, nearly doubling wheat production in a few years. The extra food produced by the Green Revolution is generally considered to have averted famine in India and Pakistan; it also allowed many developing countries to keep up with the population growth that many observers had expected would outstrip food production. The leader of a Mexican research term, U.S. agronomist Norman Borlaug, was instrumental in introducing the new wheat to India and Pakistan and was awarded the Nobel Peace Prize in 1970.

Borlaug (b. 1914) was hired in 1944 to run a wheat-research program established by the Rockefeller Foundation and the government of Mexico in an effort to make that country self-sufficient in the production and distribution of cereal grains. Borlaug's team developed varieties of wheat that grew well in various climatic conditions and benefited from heavy doses of chemical fertilizer, more so than the traditional plant varieties. Wheat yield per acre rose fourfold from 1944 to 1970. Mexico, which had previously had to import wheat, became a self-sufficient cereal-grain producer by 1956.

The key breakthrough in Mexico was the breeding of short-stemmed wheat that grew to lesser heights than other varieties. Whereas tall plants tend both to shade their neighbors from sunlight and topple over before harvesting, uniformly short stalks grow more evenly and are easier to harvest. The Mexican dwarf wheat was first released to farmers in 1961 and resulted in a doubling of the average yield. Borlaug described the twenty years from 1944 to 1964 as the "silent revolution" that set the stage for the more dramatic Green Revolution to follow.

In the 1960s, many observers felt that widespread famine was inevitable in the developing world and that the population would surpass the means of food production, with disastrous results in countries such as India. The United Nations Food and Agriculture Organization calculated that 56 percent of the human race lived in countries with an average per-capita food supply of 2,200 calories per day or less, which is barely at subsistence level (cited by Mann, p. 1038). Biologist Paul Ehrlich predicted in his 1968 bestseller The Population Bomb that "hundreds of millions" would starve to death in the 1970s and 1980s "in spite of any crash programs embarked upon" at the time he wrote his book (Ehrlich, p. xi).

In 1963, just such a devastating famine had threatened India and Pakistan. Borlaug went to the subcontinent to try to persuade governments to import the new varieties of wheat. Not until 1965 was Borlaug able to overcome resistance to the relatively unfamiliar crop and its foreign seeds and bring in hundreds of tons of seed to jump-start production. The new plants caught on rapidly. By the 1969–1970 crop season—about the time Ehrlich was dismissing "crash programs"—55 percent of the 35 million acres of wheat in Pakistan and 35 percent of India's 35 million acres of wheat were sown with the Mexican dwarf varieties or varieties derived from them. New production technologies were also introduced, such as a greater reliance on chemical fertilizer and pesticides and the drilling of thousands of wells for controlled irrigation. Government policies that encouraged these new styles of production provided loans that helped farmers adopt it.

Wheat production in Pakistan nearly doubled in five years, going from 4.6 million tons in 1965 (a record at the time) to 8.4 million tons in 1970. India went from 12.3 million tons of wheat in 1965 to 20 million tons in 1970. Both nations were self-sufficient in cereal production by 1974.

As important as the wheat program was, however, rice remains the world's most important food crop, providing 35–80 percent of the calories consumed by people in Asia. The International Rice Research Institute in the Philippines was founded in 1960 and was funded by the Ford and Rockefeller Foundations, the government of the Philippines, and the U.S. Agency for International Development. This organization was to do for rice what the Mexican program had done for wheat. Scientists addressed the problem of intermittent flooding of rice paddies by developing strains of rice that would thrive even when submerged in three feet of water. The new varieties produced five times as much rice as the traditional deepwater varieties and opened flood-prone land to rice cultivation. Other varieties were dwarf (for the same reasons as the wheat), or more disease-resistant, or more suited to tropical climates. Scientists crossed thirty-eight different breeds of rice to create IR8, which doubled yields and became known as "miracle rice." IR8 served as the catalyst for what became known as the Green Revolution. By the end of the twentieth century, more than 60 percent of the world's rice fields were planted with varieties developed by research institutes and related developers. A pest-resistant variety known as IR36 was planted on nearly 28 million acres, a record amount for a single food-plant variety.

In addition to Mexico, Pakistan, India, and the Philippines, countries benefiting from the Green Revolution included Afghanistan, Sri Lanka, China, Indonesia, Iran, Kenya, Malaya, Morocco, Thailand, Tunisia, and Turkey. The Green Revolution contributed to the overall economic growth of these nations by increasing the incomes of farmers (who were then able to afford tractors and other modern equipment), the use of electrical energy, and consumer goods, thus increasing the pace and volume of trade and commerce.

As successful as the Green Revolution was, the wholesale transfer of technology to the developing world had its critics. Some objected to the use of chemical fertilizer, which augmented or replaced animal manure or mineral fertilizer. Others objected to the use of pesticides, some of which are believed to be persistent in the environment. The use of irrigation was also criticized, as it often required drilling wells and tapping underground water sources, as was the encouragement of farming in areas formerly considered marginal, such as flood-prone regions in Bangladesh. The very fact that the new crop varieties were developed with foreign support caused some critics to label the entire program imperialistic. Critics also argued that the Green Revolution primarily benefited large farm operations that could more easily obtain fertilizer, pesticides, and modern equipment, and that it helped displace poorer farmers from the land, driving them into urban slums. Critics also pointed out that the heavy use of fertilizer and irrigation causes long-term degradation of the soil.

Proponents of the Green Revolution argued that it contributed to environmental preservation because it improved the productivity of land already in agricultural production and thus saved millions of acres that would otherwise have been put into agricultural use. It is estimated that if cropland productivity had not tripled in the second half of the twentieth century, it would have been necessary to clear half of the world's remaining forest-land for conversion to agriculture (Brown, Eco-Economy).

However, the rates at which production increased in the early years of the program could not continue indefinitely, which caused some to question the "sustainability" of the new style. For example, rice yields per acre in South Korea grew nearly 60 percent from 1961 to 1977, but only 1 percent from 1977 to 2000 (Brown et al., State of the World 2001, p. 51). Rice production in Asia as a whole grew an average of 3.2 percent per year from 1967 to 1984 but only 1.5 percent per year from 1984 to 1996 (Dawe, p. 948). Some of the leveling-off of yields stemmed from natural limits on plant growth, but economics also played a role. For example, as rice harvests increased, prices fell, thus discouraging more aggressive production. Also, population growth in Asia slowed, thus reducing the rate of growth of the demand for rice. In addition, incomes rose, which prompted people to eat less rice and more of other types of food.

The success of the Green Revolution also depended on the fact that many of the host countries—such as Mexico, India, Pakistan, the Philippines, and China—had relatively stable governments and fairly well-developed infrastructures. These factors permitted these countries to diffuse both the new seeds and technology and to bring the products to market in an effective manner. The challenges were far more difficult in places such as Africa, where governments were unstable and roads and water resources were less developed. For example, in mid-1990s Mozambique, improved corn grew well in the northern part of the country, but civil unrest and an inadequate transportation system left much of the harvest to rot (Mann, p. 1038). According to the report by David Gately, with the exception of a few countries such as Kenya, where corn yields quadrupled in the 1970s, Africa benefited far less from the Green Revolution than Asian countries and is still threatened periodically with famine.

The Green Revolution could not have been launched without the scientific work done at the research institutes in Mexico and the Philippines. The two original institutes have given rise to an international network of research establishments dedicated to agricultural improvement, technology transfer, and the development of agricultural resources, including trained personnel, in the developing countries. A total of sixteen autonomous centers form the Consultative Group on International Agricultural Research (CGIAR), which operates under the direction of the World Bank. These centers address issues concerning tropical agriculture, dry-area farming, corn, potatoes, wheat, rice, livestock, forestry, and aquatic resources, among others.

Future advances in agricultural productivity depend on the development of new varieties of plants such as sorghum and millet, which are mainstays in African countries and other less-developed areas, and on the introduction of appropriate agricultural technology. This will probably include biotechnology—the genetic alteration of food plants to give them desirable characteristics. For example, farmers in Africa are plagued by hardy, invasive weeds that can quickly overrun a cultivated plot and compel the farmer to abandon it and move on to virgin land. If the plot were planted with corn, soybeans, or other crops that are genetically altered to resist herbicide, then the farmer could more easily control the weeds and harvest a successful crop. Scientists are also developing a genetically modified strain of rice fortified with vitamin A that is intended to help ward off blindness in children, which will be especially useful in developing countries. While people have expressed concern about the environmental impact of genetically modified food plants, such plants are well established in the United States and some other countries and are likely to catch on in the developing world as well.

Bibliography

Borlaug, Norman. "The Green Revolution, Peace, and Humanity." Nobel Lecture. Delivered 11 December 1970. Available at http://www.nobel.se.

Brown, Lester R. Eco-Economy: Building an Economy for the Earth. New York: Norton, 2001.

Brown, Lester R., et al., eds. State of the World 2001: A World-watch Institute Report on Progress Toward a Sustainable Society. New York: Norton, 2001.

Dawe, David. "Re-Energizing the Green Revolution in Rice." American Journal of Agricultural Economics 80 (1998): 948–953.

Easterbrook, Gregg. "Forgotten Benefactor of Humanity." TheAtlantic Monthly 279, no. 1 (January 1997): 75–82.

Ehrlich, Paul R. The Population Bomb. Revised and expanded. New York: Sierra Club / Ballantine, 1971. A reprint of the 1968 edition.

Gately, David. "Backgrounder: The Past 25 Years: Successes, Failures, and Lessons Learned in Feeding the World." International Food Policy Research Institute, Washington, D.C., 2001. Available at http://www.ifpri.cgiar.org/2020/backgrnd/25years.htm.

Lappé, Frances Moore, Joseph Collins, and Peter Rosset. WorldHunger: 12 Myths. New York: Grove Press, 1998.

Mann, Charles. "Reseeding the Green Revolution." Science 277 (1997): 1038–1043.

Walsh, John. "The Greening of the Green Revolution." Science 242 (1991): 26.

—Richard L. Lobb

The increase in the world production of cereals such as wheat and rice during the 1960s and 1970s because of better seed and new agricultural technology.

• Business and Science of Agriculture - green revolution: introduction of high-yield crops and use of improved agricultural techniques, esp. in underdeveloped nations, to increase food production
• Cultural Movements, Events, and Institutions - green revolution: increased food production for underdeveloped nations through improved agricultural methods