Increasing the water use efficiency and fertilizer use efficiency are the key issues of water saving agriculture and dry farming. A research of different fertilization methods on crop water and nitrogen use, crop yield and biological characteristics was conducted based on the fertilization experiment on dry-land in Loess plateau. The main conclusions were drawn as follows: The biomass and grain yield have been increased by application of fertilizer. With the increasing of nitrogen and phosphorus application, the biomass and grain yield of winter wheat were increased within a certain range. The harvest index in wheat increased with N applied amount growing and decreased with P applied amount growing. During the whole growth period, the dry matter accumulation changed as an S curve and the change law for accumulation rate obvious: slow-fast-slow. Returning green to flowering was an important stage of dry matter accumulation. Increasing N-fertilizer and P-fertilizer can obviously improve the dry matter accumulation and fertilizers cooperating application was useful to increase the dry matter accumulation rate.Diurnal fluctuation of physiological rate (Pn) of winter wheat leaf was a not obvioustwo-hump curve anddiurnal fluctuation of transpiration rate (Tr) was a typical resupinate “U” and the Pn and Tr in a.m. were distinctly higher than in p.m., but the time at which the maximum appeared was different in different growth stage. The time of maximum appeared of Tr and Pn was same in elongation stage and the time of maximum appeared of Tr was later than that of Pn in grain filling stage. The influence of environmental factors on physiologic indexes in elongation stage was more obvious than that in grain filling stage. The most important environmental influencing factorson Pn and Tr were photosynthetic active radiation (PAR) and CO2 concentration. The influence of Temperature (T) and relative humidity (RH) on stomatal conductance (Gs) was progressively increased and the influence on intercellular CO2 concentration was obvious. The diurnal fluctuation of water use efficiency was a not obvioustwo-hump curve and the time of maximum appeared was earlier than those of Pn and Tr. The daily mean WUE in filling stage was lower than that in elongation stage to 30.5%.The correlations among Pn, Tr and Cond were very significant and there was a significant negative correlation between temperature of leaf and Gs. The correlation inconsistency betweentemperature of leaf and Pn, Tr revealed that the wheat had some adaptability to dry because of the deficiency of precipitation in Loess plateau and this is an opportunity in cultivating wheat of high WUE.Increasing nitrogen application decreased the leaf WUE in prior period of growing periods but increased it in later period and increased the LAI of wheat. There were no obvious impacts on leaf WUE and LAI by increasing the phosphate fertilizer. Increasing nitrogen application significantly increased WUE in level of biomass and yield by increasing biomass and field of wheat and more phosphate fertilizer application increased the biomass and yield but were no significant impacts on WUE in level of biomass and yield. Correlation analysis between biomass, yield, LAI and WUE were significantly correlated because of increasing the LAI of wheat by fertilizing and then increasing the photosynthetic efficiency of population and accumulation of dry matter and increasing the WUE finally.During the whole growth period, the SPAD reading values of winter wheat changed as a resupinate ”L” curve. With the increasing of N-fertilizer amount, the SPAD was obviously increased but SPAD showed downtrend with the increasing of P-fertilizer amount at filling stage. The nitrogen content in root, stem, leaf and ear of winter wheat were increased with the increasing of nitrogen application. The nitrogen content of root showed downtrend with the increasing of phosphorus application and phosphorus application excess may lead to the loss of nitrogen in ear of winter wheat at filling to maturity. The changing tendency of grain filling rate was similar to accumulation rate of seed and increased at earlier growth stage then decreased at late growth stage. The changing tendency of nitrogen in seed was opposite to that of grain filling rate. The peak of grain filling rate and nitrogen accumulation rate was increased by increasing the nitrogen application. The nitrogen accumulation in a seed of winter wheat was in sequence of N1> N1P2> N1P1>CK. The biomass of winter wheat was obviously increased by increasing the nitrogen and phosphorus application, thus increasing the nitrogen accumulation per unit area, but the nitrogen accumulation in a seed was hardly increased.
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