Effect of Combined Application of Nitrogen and Phosphorus on Photosynthesis Parameters at Grain-filling Stage and Grain Yield in Winter Wheat
The effect of nitrogen and phosphorus fertilizer on photosynthetic characteristics and grain yield of winter wheat were investigated in the Northwest Oasis area of China.Four treatments were 2 for nitrogen (165 and 225 kg·hm-2) and 2 for phosphorus (105 and 165 kg·hm-2).With low N application (N1P1,N1P2),the diurnal variations of net photosynthetic rate (Pn),stomatal conductance (Gs) and transpiration rate (Tr) were presented as double-peak curves,with obvious midday decrease in photosynthesis.With high N (N2P1,N2P2),the midday decrease in photosynthesis weakened or even disappeared.Fertilizer P had less effect on the photosynthesis as compared with N.Among the fertilization treatments,treatment N2P2 conferred the highest leaf area index,canopy apparent photosynthetic rate (CAP),grain number,spike number,1 000 grain weight and grain yield as compared with N1P1 and N1P2,but not N2P1.Water-use efficiency was lower with N2P2 than N2P1 and significantly higher for both N1P1 and N1P2,with no difference between N1P1 and N1P2.Fertilizer N had greater effect on the midday decrease in photosynthesis than P,but the combined application of N and P had no significant co-effect.A combined application of 225 (N) and 105 kg·hm-2 (P) enhanced Pn and grain yield.
国家科技期刊平台
NSTL
万方数据
维普
