The Green Revolution was a movement by which methods of agriculture in many developing nations were radically changed, leading to a significant increase in agricultural output. As a result of an agricultural breakthrough, seeds were modified to increase crop yield. Strains of maize, wheat and rice were created that are referred to high-yielding varieties (HYVs). These HYVs were more responsive to petrochemical fertilizers and controlled irrigation, and produced more than the original varieties.
The Green Revolution grew and flourished, and by the 1970s, the new seeds accompanied by chemical fertilizers, pesticides and irrigation had replaced traditional farming practices in several developing countries. One of the most important features of the Green Revolution was double cropping, which was made possible by improved irrigation facilities, because of which the farmer could harvest two crops in a year, rather than one. Other basic elements of the Green Revolution were continuing expansion of farming areas, increase in the use of chemical fertilizers, increase in the use of irrigation facilities and utilization of HYV seeds.
 Spread of the Green Revolution
In the mid-1940s, Mexican researchers developed a variety of wheat that was able to convert fertilizer and water into high yields. These new and improved seeds boosted Mexican wheat production and were instrumental in averting famine in India and Pakistan. Norman E. Borlaug, leader of the Mexican team, was awarded the 1970 Nobel Peace Prize for his efforts. There were even significant improvements in corn production.
A similar rice research effort was started in the Philippines and a network of research centres — dedicated to food crops and environments of developing countries — was established. By 1992, this network had 18 centres, mostly in developing countries, supported by global scientists, foundations, national governments and international agencies.
By the 1990s, almost 75 per cent of rice areas in Asia were sown with HYV seeds. Half the wheat planted in Africa and more than half in Latin America and Asia were planted with these varieties. Similarly, 70 per cent of corn planted was of the high-yielding variety.
 Effects of the Green Revolution
Though it brought self sufficiency in foodgrains in some regions, the Green Revolution has had several negative ecological and social effects across the world.
- Ecological effects: Large farms were established where HYV crops were cultivated. These crops needed plenty of inorganic fertilizers, pesticides, fungicides and other chemicals. Effects of exposure to chemicals such as DDT were revealed to be carcinogenesis and mutagenesis. Residues of these toxins are still present in the soil, even 20 years later. Agricultural pesticides have brought about the creation of resistant pests, new pests and have intensified pest outbreaks. In some places, over-irrigation led to salination of soil, changing its composition. Hence, use of HYV seeds has, in effect, rendered large areas of land infertile.
- Social effects: Socially, the Green Revolution has had a negative impact, especially in developing nations, where it was instrumental in widening the gap between the rich and the poor. The farmers who were already well off could afford expensive agricultural inputs and got government support for irrigation facilities, subsidized rates in power supply, low rate of interest loans etc. The poorer farmers could not afford to invest in these agricultural inputs and their situation remained the same. Hence, the Green Revolution was unable to accomplish self-sustainability of the rural people, and instead caused increased inequity and social unrest. The Green Revolution replaced traditional methods of farming with modern techniques, hence disturbing the traditional set up in many Asian countries, where agriculture has a close relationship with religion and culture.
 References and Useful Websites
- Frank Environmental Education by Reeta David