Effectofintermittentirrigationontheproductionofpaddyricewasstudiedinawell-puddledpaddyfieldwithfourtreatmentsand2replicates:continuoufloodingirrigation(CFI),andintermittentirrigationⅡ-0，Ⅱ-1andⅡ-2,inwhichplantswerere-irrigatedwhenthesoilwaterpotentialfellbelow0,-10,and-20toabout-10or-20kPadidnotsignificantlyaffectthenumberofgrainsandthepercentageofripenedgrains.While,alowercropgrowthrate(CGR)resultedfromadecreaseinthenetassimilationrate(NAR)duringintermittentirrigationⅡ-1andⅡ-2,andtherewasalsoareductionintheleafareaindex(LAI)durinindtermittentirrigationⅡ-2.SenescenceoflowerleavesonstemswaspromotedintreatmentsⅡ-1andⅡ-2attheripeningstage.Earlysenescenceatripeningstageandwaterstressaroundmiddaydecreasedtherateofphotosynthesisinleaves,causingthelowerNAR,Thesephysiologicalresponsesoftheplantswereresponsibleforthereductioninthedrymatterproductionandgrainyieldintheintermmittentirrigationtreatments.
