Effects of water stress on leaf photosynthetic characteristic in leaf of rice of different genotypes

In order to promulgate the mechanism of the decrease of photosynthesis characteristic under water stress,the effects of short water stress treatments on rice leaf photosynthetic characteristic were studied with rice seedling solution experiments under water stress.The results indicated that the photosynthetic characteristic reduced obviously,0~30 min arid fluorescence kinetic parameter,Fv/Fm,Φ PS Ⅱ,Qp,NPQ showed different changes,and NPQ showed slightly rising trend,other indicators were lower,but the decline was generally smaller,Fv/Fm,qp and ΦPSⅡ decreased quickly after being present to 90 min treatment.NPQ began to decrease at 120 min,which marked an obvious effect on the photosynthetic apparatus of leaf.The changes of photosynthetic characteristic were restricted stomatal limitation and non-stomatal limitation,and the damages of photosynthetic apparatus was the main reason of the decrease of photosynthetic efficiency.