Study On Compensation Effect Of Rice After Rewatering

Pot experiment was conducted to study the compensation effect of rice under water stress. The results indicated that the compensation effect of water stress on physiological characteristics yield and water use efficiency(WUE)were likely to appear after stress period. Degree of compensation effects depends on water stress duration, stress severity, stress periods and nourishment condition after water stress.1. Rewatering after water stress advanced the optimal/maximal photochemical efficiency of PS II in the dark(Fv/Fm) of rice leaves, all different leaves had compersation, and the new ones were obviously. The diefferent leaves had different performance on photosynthesis, the new-born leaves had photosynthesis compersation.2. Rewatering after water stress improved the capability of leaves to resist light inhibiting, changed the numerical value of fluorescence and photosynthesis but the trendof day diversification.3. Applation of nitrification after water stress , advanced the stomatic conductance and the optimal/maximal photochemical efficiency of PS II in the dark, boosted up photosynthesis ability of rice leaves. The trend of the day diversification of fluorescence and photosynthesis were aslo afected by application of nitrification .4. Water stress acombined with nitrification advanced the photosynthesis of rice leaves, reduced the root/shoot ratio, and changed the relationship between storage and source of rice, stimulated assimilation transported to grain. Severe stress in adding nitrification tillering stage and mild stress in jointingstageadding nitrification highed the yield obviously .