Efficacy of qFL-chr1, a Quantitative Trait Locus for Fiber Length in Cotton (Gossypium spp.)

Inanearlieradvanced-backcrossquantitative� traitlocus�(QTL)�analysisofaninterspecificGos- sypium hirsutumL.��Gossypium barbadenseL.� population,�28�fiberlengthQTLswereidentified� includingqFL-chr1� onchromosome� 1� ofthe� A-subgenome.�TheG. barbadensealleleatthis� QTLcontributedtolongerfibersandexplained� upto�24%�ofthephenotypicvariance.�Tosub- stantiatetheassociationofthisgenomicregion� withfiberlength,� threeBC 3 F 2 � plantsheterozy- gousforthegeneticmarkersthatdelineatethe� qFL-chr1�QTLwereselectedtoconstructthree� independentpopulationsofnear-isogenicintro- gressionlines� (NIILs).� TheefficacyofqFL-chr1� wasevaluatedamong� 140� NIILsgrownin� 2� yr.� TheresultssupportthepositiveeffectofqFL- chr1� onfiberlength.� AsingleNIIL,� R01-40-08,� hadabout� 94.3%� ofrecurrentgenomecom- positionandsignificantlylongerfiberthanthe� recurrentparentwhengrowninNanjing,�China.� Therefore,�inadditiontoconfirmingtheefficacy� ofqFL-chr1� toenhancefiberlength,� thiswork� providesavaluablegeneticresourceforthe� improvementofcotton.