Moleculardesignbreedingisoneofstraightforwardapproachestobreakyieldbarriersinrice.Inthisstudy,GW6geneforgrainlengthandwidthfromBaodaliwastransferredintoanindicarecurrentparent9311andajaponicavarietyZhonghua11(ZH11)usingmarker-assistedbackcross(MAB).Oneandthreeintrogressionlineswereselectedforphenotypicanalysisfrom9311andZH11geneticbackgrounds,respectively.SSL-1,animproved9311nearisogeniclinewithGW6performed11%,19%and6.7%higherofgrainlength,1000-grainweightandsingleplantyield,respectively,ascomparedwith9311.AllthethreeimprovedZH11-GW6lines,R1,R2andR3,hadmorethan30%increaseingrainweightandabout7%higheringrainyield.SeedplumpnessofR1,R2andR3wasimprovedsynchronouslybecausethethreeZH11-GW6linescontainedGIF1(GrainIncompleteFilling1),adominantgrainfillinggene.Thus,GW6hashighpotentialinincreasingtheyieldofinbredlinesthroughMAB,makingitanimportantgeneticresourceinsuperhybridricebreeding.ThisstudyprovidesinsightsintheutilizationofGW6forlargegrainandhighyieldricebreedingviamoleculardesignbreeding.
