简介：Theperformanceandinheritanceof7qualitytraitswerestudiedusingF2ricegrainderivedfrom8×8diallelcrossingmadebyemploying8parentsofdifferentecologicaljaponicaricetypes.Differencesineachtraitamong8parentswerenotobvious,butinF2generation,transgressivephenomenawerefoundinallthetraitsstudied,indicatingthatthegenescontrollingthesetraitsamongparentsweresegregated.Theinheritanceofgrainwidth,grainweight,chalkinessscore(CS),gelatinizationtemperature(GT)andgelconsistency(GC)weresuitabletoadditive-dominantmodel,anddominanteffectcontributedmainlyforthe5traits.Theinheritanceofgrainlength(GL)andamylosecontent(AC)didnotfitintoadditive-dominantmodel,existingepistaticinteractions.Dominantgenesforgrainwidthandgrainweighthadtheefficiencyofdecreasingeffect,anddominantgenesforCS,GTandGChadtheefficiencyofenhancingeffect.Koshihikaricontainedmorerecessivegenesforgelatinizationtemperaturethanothervarieties.Zhendao88hadmoredominantgenesingrainwidthandgrainweightthanothervarieties.Xiushui04possessedmoredominantgenesforGLandGC,andmorerecessivegenesforCSthanothervarieties.

简介：Apopulationofricebrownplanthopper(BPH)NilaparvatalugenscollectedfromapaddyfieldinHangzhouwassuccessivelyrearedonsusceptiblericeTaichungNative1(TN1)inalaboratoryfreefrominsecticidesformorethan14generations.Thechangesinsusceptibilitytoinsecticidesandecologicalfitnessondifferentresistantricevarietiesweremonitoredineachgeneration.Theresistanceratiotoimidaclopridsharplydeclinedwiththesuccessionofrearinggenerationswithoutinsecticidesfrom359.94-foldatF1to6.50-foldatF14comparedwiththesusceptiblestrain,andtheresistanceratiotochlorpyrifoswasfrom9.90-foldatF1to5.94-foldatF14.Nymphaldurationandweightsofnewlyhatchedfemaleadultsweresignificantlyaffectedbyricevariety,generationandtheirinteractions,butnymphalsurvivalwassignificantlyaffectedbythegenerationonly.Theratioofbrachypterousadultsinmaleswasaffectedbythegenerationandgeneration×varietyinteraction,whereasnodifferencewasfoundinfemales.Nymphaldurationextendedwithincreasinggenerations,andthefemalenymphaldurationwasshorterinthesusceptiblevarietyTN1thanthoseintheresistantvarietiesIR26andIR36.Inaddition,thefemaleadultweightinTN1washigherthanthoseinIR26andIR36.TheseresultsindicatedthattheresistanceoffieldBPHpopulationtoinsecticideswasreversedafterseveralgenerationsofno-exposuretoinsecticides,andtheecologicalfitnessinTN1washigherthanthoseinIR26andIR36.ThesefindingssuggestedtherationalandreduceduseofinsecticidesincombinationwiththemanipulationofresistantricevarietieswouldbeeffectiveforBPHmanagement.