Alightbrownspotted-leafmutantofricewasisolatedfromanethanemethylsulfonate(EMS)-inducedIR64mutantbank.Themutant,designatedaslbsl1(lightbrownspotted-leaf1),displayedlightbrownspotinthewholegrowthperiodfromthefirstleaftotheflagleafundernaturalsummerfieldconditions.Agronomictraitsincludingplantheight,growthduration,numberoffilledgrainsperpanicle,seed-settingrateand1000-grainweightofthemutantweresignificantlyaffected.Geneticanalysisshowedthatthemutationwascontrolledbyasinglerecessivegene,tentativelynamedlbsl1(t),whichwasmappedtotheshortarmofchromosome6.Bydevelopingsimplesequencerepeat(SSR)markers,thegenewasfinallydelimitedtoanintervalof130kbbetweenmarkersRM586andRM588.Thelbsl1(t)geneislikelyanovelricespotted-leafgenesincenoothersimilargeneshavebeenidentifiednearthechromosomalregion.Thegeneticdataandrecombinationpopulationsprovidedwillfacilitatefurtherfine-mappingandcloningofthegene.
