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Green Revolution. Period beginning in 1940’s in which plant geneticists, used traditional methods of cross-breeding plants with desirable traits Plants selected for l arger , more nutritious seeds,fruit and/or for resistance to pest and disease Focused chiefly on wheat, corn, and rice.
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Green Revolution • Period beginning in 1940’s in which plant geneticists, used traditional methods of cross-breeding plants with desirable traits • Plants selected for larger, more nutritious seeds,fruit and/or for resistance to pest and disease • Focused chiefly on wheat, corn, and rice Norman Borlaug
Successes • As a result of the Green Revolution in the 1960's, 70's and 80's, crop yields soared in India, China and Latin America • Lower food prices globally • Where food remained scarce in these countries, may have been the result of politics and planning not lack of food
Side effects of successes • Uneven development • Displacement of small farmers • Increased dependency of small farmers on global markets • Dependency upon fossil fuels • Increased pesticide use • Changes in crop diversity and plant nutritional content
Uneven development • Not all locations benefited from Green Revolution • Crop yields average 1,500 pounds of cereals per acre in Africa compared with 2,300 pounds in India and 4,900 pounds in China in 2004. • Africa lagged in part because of political instability and lack of infrastructure. • Breeding targeted only certain crops that grow in rich soils with ample access to water. Plants for marginal lands not targeted • “Asking many African farmers to invest in Green Revolution technology meant asking them to invest in fragile plants in a harsh landscape."
Displacement and dependency of small farmers • Promotion of industrial agriculture • Neoliberalization • Monoculture export crops grown on plantations replaced diverse types of traditional agriculture • Conversion of natural lands • Land became concentrated with large landholders who can afford land and the cost of inputs
Displacement and dependency of small farmers • Food crops replaced by export products • Profits susceptible to changes in global markets • New crop types did not fit into local cultures • Export products have limited use as food • Suicides among Indian farmers
Loss of agricultural resilience • Goal was to eliminate variability and maximize production • Increased dependency upon • Irrigation • Fossil fuels for tractors, production of chemical inputs (pesticides), and for fertilizer production • More “brittle” system resulted • This is a hallmark of the command and control approach to resource management Haber process of fertilizer production
Increased chemical exposures Acute and chronic toxicity MutagenicTeratogenicEndocrine disruption Epigenetic effects Childhood and in utero exposures may result in slow mental development and ADHD disorders
Changes in plants and their foods • Loss of nutritional content
Loss of genetic diversity • Crop plants no longer resemble plant they were domesticated from • Uniformity in genetic makeup increases susceptibility to disease • On average, across all crops grown in the US. over 90% of the varieties grown 100 years ago are no longer in commercial production or maintained in major seed storage facilities. • In 1903, US seed catalogs listed 408 pea varieties; only 25 can be found now (a 95% decrease) and by 1970, just two pea varieties comprised 96% of the US commercial crop. • Nine varieties of wheat occupy half of all the wheat land in the US.
Loss of genetic diversity • A landrace is a local variety of a domesticated animal or plant species which has developed largely by adaptation to the natural and cultural environment in which it lives. • Landraces are usually more genetically and phenotypically (physically) diverse than formal breeds. • Landraces are analogous to heirloom varietals
In India farmers have planted 30,000 different varieties of rice over the past 50 years, with the varieties grown in a region closely matched to its soils, climate and so forth. With the advent of green revolution varieties, this has changed. It is estimated that 75% of all rice fields in India were planted to just 10 varieties in 2005.