IR8 is a high-yielding semi-dwarf rice variety developed by the International Rice Research Institute (IRRI) in the early 1960s. It was developed by a
IRRI team
consisting of Peter Jennings, Henry Beachell, Akira Tanaka, Te-Tzu Chang, Surajit Kumar De Datta, and Robert F. Chandler.

Research

IR8 was the eighth of 38 crossbred rice varieties in a 1962 experiment by IRRI. It was a cross of Peta, a high yield rice variety from

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

, and Dee-geo-woo-gen (DGWG), a dwarf variety from

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

. The ''semidwarf-1'' gene (sd-1 or Os01g0883800), which encodes an

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

in the production of the hormone

gibberellin Gibberellins (GAs) are plant hormones that regulate various Biological process, developmental processes, including Plant stem, stem elongation, germination, dormancy, flowering, flower development, and leaf and fruit senescence. They are one of th ...

, which affects plant height; this improved its yield. IR8 was well suited to the places it was first introduced. However, it “did not fit most rice-growing situations,” which involve heavy

monsoon A monsoon () is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in Atmosphere of Earth, atmospheric circulation and precipitation associated with annu ...

s or deep flooding.

Cultivation

In November 1966, IR8 was introduced in the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

and India. Promoters such as the IRRI and farmer benefactors of IR8 have called it 'miracle rice', and celebrate it for fighting famine. IR8 dramatically increased the yields of Asian rice from 1 or 2 ton per hectare to 4 or 5 tons per hectare.World Food Prize Foundation 1996 Laureate: Beachell and Khush
worldfoodprize.org It played a significant part in the

Green Revolution The Green Revolution, or the Third Agricultural Revolution, was a period during which technology transfer initiatives resulted in a significant increase in crop yields. These changes in agriculture initially emerged in Developed country , devel ...

References

Rice varieties {{poaceae-stub