From the 1950s to 1970s, in an effort to combat world hunger, plant breeders at the International Rice Research Institute (IRRI) in the Philippines developed new rice varieties that were, when fertilized, higher yielding than traditional varieties. The new varieties were shorter and less likely to fall over, which made them easier to harvest mechanically. They also ripened sooner, reducing the risk of poor weather affecting yield, and enabling farmers to harvest and replant several times during the growing season. While successful in many areas, the new varieties required more money for fertilizer and chemical pesticides, and in some cases, machines for sowing and harvesting—tools often too costly for peasant farmers. In some areas a single new rice variety replaced diverse, centuries-old varieties adapted to thrive in a particular climate and soil type and with some resistance to local insects and diseases. The new variety was not able to thrive in these areas, and the crop yields were not always greater.Rice breeders at IRRI and other research facilities are now trying to increase yields through genetic engineering. They hope to create rice varieties that are genetically designed to require less fertilizer, resist insects and diseases, tolerate poor soil, require less irrigation, and photosynthesize more efficiently.
Scientific classification: Rice is an annual grass in the grass family, Poaceae (formerly Gramineae). Asian rice is classified as Oryza sativa and African rice as Oryza glaberrima.
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