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Hybrid rice is any genealogy of rice produced by crossbreeding different kinds of rice. As with other types of hybrids, hybrid rice typically displays heterosis (or hybrid vigor) such that when it is grown under the same conditions as comparable high-yielding inbred rice varieties it can produce up to 30% more rice.〔(About hybrid rice ), from the International Rice Research Institute.〕 High-yield crops, like hybrid rice, are one of the most important tools for combating world food crises. The earliest high-yield rice was cultivated by Henry 'Hank' Beachell in 1966, but it was not until the 1974 that the first hybrid rice varieties were released in China.〔(Hybrid rice ), International Rice Research Institute〕 In crop breeding, although the use of heterosis in first-generation seeds (or F1) is well known, its application in rice was limited because of the self-pollination character of that crop. In 1974, Chinese scientists successfully transferred the male sterility gene from wild rice to create the cytoplasmic genetic male-sterile (CMS) line and hybrid combination. The first generation of hybrid rice varieties were three-line hybrids and produced yields that were about 15 to 20 percent greater than those of improved or high-yielding varieties of the same growth duration. At the present time, Yuan Longping, the "Father of Hybrid Rice", may be the most famous in research on hybrid rice. In the 1970s, he made his seminal discovery of the genetic basis of heterosis in rice. This was a unique discovery because it had been previously thought that heterosis was not possible for self-pollinating crops such as rice.〔(Hybridizing the world - The father of hybrid rice ), Rice Today (Oct-Dec, 2010)〕 According to the China Daily, in 2011, Yuan developed a new hybrid rice that can produce 13.9 tons of rice per hectare.〔(Hope from hybrid rice ), China Daily, 21 September 2011.〕 In China, hybrid rice is estimated to be planted on more than 50% of rice-growing land there and it is credited with helping the country increase its rice yields, which are among the highest within Asia. Hybrid rice is also grown in many other important rice producing countries including Indonesia, Vietnam, Myanmar, Bangladesh, India,〔Oudhia P, Pandey N, Ganguli RN & Tripathi RS (1999) Gall midge (Orseolia oryzae) infestation in hybrid rice as affected by agronomical practices. Insect Environment 4: 123–124.〕 Sri Lanka, Brazil, USA, and the Philippines.〔(Hybrid rice history ), International Rice Research Institute.〕 A 2010 study published by the International Rice Research Institute (IRRI), reports that the profitability of hybrid rice in three Indian states varied from being equally profitable as other rice to 34% more profitable.〔(IRRI Technical Bulletin No.14 - Hybrid rice adoption in India: farm level impacts and challenges )〕 Outside of China other institutes are also researching hybrid rice, including the International Rice Research Institute, which also coordinates the (Hybrid Rice Development Consortium ).〔(Our science: Hybrid rice ), International Rice Research Institute.〕 ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hybrid rice」の詳細全文を読む スポンサード リンク
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