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1、HybridRiceHybridriceisanygenealogyofriceproducedbycrossbreedingdifferentkindsofrice.Aswithothertypesofhybrids,hybridricetypicallydisplaysheterosis(orhybridvigor)suchthatwhenitisgrownunderthesameconditionsascomparablehigh-yieldinginbredricevarietiesitcanproduceu
2、pto30%morerice.High-yieldcrops,likehybridrice,areoneofthemostimportanttoolsforcombatingworldfoodcrises.Theearliesthigh-yieldricewascultivatedbyHenry'Hank'Beachellin1966,butitwasnotuntilthe1974thatthefirsthybridricevarietieswerereleasedinChina.Incropbreeding,alt
3、houghtheuseofheterosisinfirst-generationseeds(orF1)iswellknown,itsapplicationinricewaslimitedbecauseoftheself-pollinationcharacterofthatcrop.In1974,Chinesescientistssuccessfullytransferredthemalesterilitygenefromwildricetocreatethecytoplasmicgeneticmale-sterile
4、(CMS)lineandhybridcombination.Thefirstgenerationofhybridricevarietieswerethree-linehybridsandproducedyieldsthatwereabout15to20percentgreaterthanthoseofimprovedorhigh-yieldingvarietiesofthesamegrowthduration.Atthepresenttime,YuanLongping,the"FatherofHybridRice",
5、maybethemostfamousinresearchonhybridrice.Inthe1970s,hemadehisseminaldiscoveryofthegeneticbasisofheterosisinrice.Thiswasauniquediscoverybecauseithadbeenpreviouslythoughtthatheterosiswasnotpossibleforself-pollinatingcropssuchasrice.AccordingtotheChinaDaily,in2011
6、,Yuandevelopedanewhybridricethatcanproduce13.9tonsofriceperhectare.InChina,hybridriceisestimatedtobeplantedonmorethan50%ofrice-growinglandthereanditiscreditedwithhelpingthecountryincreaseitsriceyields,whichareamongthehighestwithinAsia.Hybridriceisalsogrowninman
7、yotherimportantriceproducingcountriesincludingIndonesia,Vietnam,Myanmar,Bangladesh,India,SriLanka,Brazil,USA,andthePhilippines.[8]A2010studypublishedbytheInternationalRiceResearchInstitute(IRRI),reportsthattheprofitabilityofhybridriceinthreeIndianstatesvariedfr
8、ombeingequallyprofitableasotherriceto34%moreprofitable.OutsideofChinaotherinstitutesarealsoresearchinghybridrice,includingtheInternationalRiceResearchInstitute,whichalsocoor
