Nearisogeniclinescarryinglarge-effectQTL(qtl12.1),whichhasaconsistentinfluenceongrainyieldunderuplanddroughtstressconditionsinawiderangeofenvironments,wereevaluatedunderwaterstressinthefields.Thelinewhichgavehigheryieldunderdroughtwascrossedwithalocaleliteline,PMK3,andforwardedtoF2:3generation.SignificantvariationwasfoundamongtheF2:3linesforagronomictraitsunderwaterstressinthefields.Lowtohighbroadsenseheritability(H)forinvestigatedtraitswasalsofound.Waterstressindicatorssuchasleafrollingandleafdryingwerenegativelycorrelatedwithplantheight,biomassandgrainyieldunderstress.Bulkedsegregantanalysis(BSA)wasperformedwiththemarkersinthevicinityofqtl12.1,andRM27933wasfoundtobesegregatedperfectlywellininpidualcomponentsofdroughtresistantanddroughtsusceptiblebulkswhichwerebulkedbasedonyieldunderwaterstressamongF2:3lines.Hence,thissimpleandbreederfriendlymarker,RM27933,maybeusefulasapotentiallyvaluablecandidatemarkerforthetransferoftheQTLqtl12.1intheregionalbreedingprogram.BioinformaticanalysisoftheDNAsequenceoftheqtl12.1regionwasalsodonetoidentifyandanalyzepositionalcandidategenesassociatedwiththisQTLandtoascertaintheputativemolecularbasisofqtl12.1.
