简介：Forthetwo-linehybridricesystem,pollensterilityisregulatedbyrecessivegenethatrespondstotemperature.Therecessivegenecontrollingthermo-sensitivegeneticmalesterility(TGMS)isexpressedwhentheplantsaregrowninconditionswithhigherorlowercriticaltemperatures.Totransfertgmsgene(s)controllingTGMStoThairicecultivarsbybackcrossbreedingmethod,amalesterilelinewasusedasadonorparentwhileThairicecultivarsChaiNat1,PathumThani1,andSuphanBuri1wereusedasrecurrentparents.TheBC2F2linesweredevelopedfrombackcrossingandselfing.Moreover,thesimplesequencerepeat(SSR)markersweredevelopedforidentifyingtgmsgeneandthelinkedmarkerwasusedforassistingselectioninbackcrossing.Theidentificationlineswereconfirmedbypollenobservation.TheresultsshowedthesuccessofintrogressionofthetgmsgeneintoThairicecultivars.TheselineswillbetestedforcombiningabilityandusedasfemaleparentinhybridriceproductioninThailand.

简介：Introgressionlines(ILs)derivedfrominterspecificcrossesareasourceofnewgeneticvariability.Atotalof55ILsderivedfromtwocrossesSwarna×O.nivaraIRGC81848(populationA)andSwarna×O.nivaraIRGC81832(populationB)werecharacterizedforyieldandyield-relatedtraits/QTLs.Segregationof103simplesequencerepeat(SSR)markersassociatedwithyield-relatedQTLswasstudied.PopulationAshowedanaverageof12.6%homozygousO.nivaraallelesandpopulationBshowed10.6%.Interestingly,threeSSRmarkers,RM223,RM128andRM517,showedconspicuouspatternofsegregation.ThedistributionofparentalallelesatthreelociRM223,RM128andRM517linkedtoyield-relatedtraitswasunique.Thesemarkersflankedtoseveralyield-relatedQTLs.RM223,flankingtoqyld8.3,washeterozygousinalmostallthe55ILsexceptinIL10-3SandIL131S.RM128onchromosome1andRM517onchromosome3weremutuallyexclusivein46outof55ILs.These46ILsshowedeitherofthemarkeralleleRM128orRM517fromO.nivarabutnotboth.IL166ShadbothRM128andRM517fromO.nivaraandtheotherILsshowedhomozygousSwarnaalleleatRM517exceptIL65S.Populationstructureassignedthe55ILstothreesub-populationsbasedontheirgenomicdiversity.IL65S,IL166S,IL248S,IL7KandIL250Kshowedhighyieldsinmulti-locationtrials,andIL248SwasreleasedforcultivationasDRRDhan40.