Effects Of Irrigation And Phosphorus Fertilizer On Water Consumption Characteristics And Grain Yield And Its Physiological Basis In Wheat

1 The difference of water consumption characteristics and grain yield between two wheat cultivarsDifferences in water use characteristics and grain yield between different wheat cultivars was studied by using two wheat cultivars including Jimai20 (J20) which with strong gluten potential and Taishan 23 (T23) which with medium gluten potential. Setted up two treatments including no irrigation (expressed as W0), irrigation at sowing stage, jointing stage and anthesis stage (expressed as W1), the irrigation amount was 30mm once. The principal results were as follows.Under the condition of treatment W0 and W1, the grain yield and water use efficiency of Taishan 23 was higher than that of Jimai 20.1.1 The difference of water consumption characteristics between different wheat cultivarsFrom jointing to maturity, T23 was mainly using the soil moisture of 60~160cm soil layers, but J20 was mainly using the soil moisture of 60~120cm soil layers, under the condition of treatment W0. Under the condition of treatment W1, T23 was mainly using the soil moisture of 80~140cm soil layers, but J20 was mainly using the soil moisture of 60~120cm soil layers. The soil water consumption amount in 100~140cm of T23 was significantly higher than that of J20. These showed that the ability to absorb and utilize the deep soil storage water of T23 was higher than that of J20.Under the condition of treatment W0, soil water consumption amount in 120 to 140cm soil layer and the ratio of it to total soil water consumption amount of T23 was higher than that of J20, and soil water consumption amount in 60 to 100cm soil layer and the ratio of it to total soil water consumption amount of T23 was lower than that of J20. Under the condition of treatment W1, soil water consumption amount in 0 to 60cm soil layer and the ratio of it to total soil water consumption amount of T23 was higher than that of J20. These indicated that the deep soil storage water amount which absorbed by T23 was higher than J20 under the condition of treatment W0, but the upper soil storage water amount which absorbed by T23 was higher than J20 under the condition of treatment W1.Under the condition of treatment W0 and W1, soil water consumption amount at emerging to before winter and revival to jointing of T23 was lower than that of J20, and soil water consumption amount at anthesis to maturity stage of T23 was higher than that of J20, these showed that the ability to absorb and utilize the soil storage water at the earlier growing stage of T23 was lower than that of J20, and that of T23 at the late growing stage was lower than that of J20.Under the condition of treatment W0, the ratio of different water resource to total water consumption amount were not significantly between T23 and J20. Under the condition of treatment W1, the water supply content of soil and the ratio of water supply content of soil to water consumption of T23 were higher than that of J20. These showed that soil moisture utilization rate of T23 was higher than that of J20 under the condition of treatment W1.Under the treatments W0 and W1, water consumption amount of T23 was lower 2.15% and 2.36% respectively than that of J20 from sowing to pre- wintering, but it was higher 1.93% and 5.53% respectively from anthesis to maturity. 1.2 The difference of grain yield and water use efficiency between different wheat cultivarsRelative water content, photochemical efficiency, sucrose content of flag leaf and the ratio of dry matter distributed into grain of T23 were higher than that of J20 at filling stage. The grain yield and water use efficiency of T23 was higher than that of J20.2 Effects of irrigation and phosphorus fertilizer on water consumption characteristics and grain yield and its physiological basis in wheatThe effect of irrigation amount and phosphorus fertilizer rate on grain yield and water use efficiency was studied by using wheat cultivar Jimai20 which with strong gluten potential and Taishan 23 which with medium gluten potential. The experiment utilized the split-plot design with irrigation amount as main plots and fertilizers as subplots. Setted up four treatments including no irrigation (expressed as W0), irrigation at sowing stage, jointing stage and anthesis stage, the irrigation amount was 30mm (expressed as W0), 60mm (expressed as W2), 90mm (expressed as W3) once and three treatments of different phosphorus fertilizer rates: 0 kg·hm-2 (expressed as P0), 105 kg·hm-2 (expressed as P1), 210 kg·hm-2 (expressed as P2). The principal results were as follows.Grain yield of treatment P1W2 was higher than other treatments, and the water use efficiency of treatment P1W2 was higher.2.1 Effects of irrigation and phosphorus fertilizer on water consumption characteristicsUnder the condition of treatment P1, soil moisture content in 60 to 100cm and 100 to 140cm soil layer of treatment W2 was higher than that of treatment W0 and W1 at jointing to maturity stage. At the base of treatment W2, more irrigation rate increased soil moisture content in 100 to 140cm at jointing to maturity stage. These showed that 60~100cm and 100~140cm soil layers from jointing stage to maturity stage must be contained proper water content to ensure high grain yield. Under the condition of treatment P1, soil water consumption amount in 40 to 200cm soil layer of treatment W2 was higher than that of treatment W3. These showed that treatment W2 increased the soil moisture utilization rate under 40cm soil layer compared with treatment W3.Under the condition of treatment P1W2, the contribution percentage of irrigation rate to total water consumption rate of T23 and J20 were 38.22% and 39.34%, the contribution percentage of precipitation rate to total water consumption rate of T23 and J20 were 40.15% and 41.33%, the contribution percentage of soil water consumption rate to total water consumption rate of T23 and J20 were 21.36% and 19.33%. At the base of treatment W2, more irrigation rate decreased the ratio of precipitation rate and soil water consumption rate to total water consumption rate, increased the total water consumption rate.Under the condition of treatment P1W2, the amount of water consumption percentage was 42.25% and the water consumption daily was 4.60mm at the period from anthesis to maturity stage. At the base of treatment W2, more irrigation rate increased water consumption percentage not significant, but increased significantly.2.2 Effects of irrigation and phosphorus fertilizer on grain yield and water use efficiencyUnder the condition of treatment P1, treatment W2 increased the Fv/Fm,фPSⅡ, sucrose content, the endopeptidase activity and free amino acid content of flag leaf. These showed that treatment W2 raised source supply ability in grain yield and protein formation. At the base of treatment W2, more irrigation rate decreased the transformation of the source and the amino acid from vegetative parts to grain during middle and late filling stage, and it went against the formation of grain weight and grain protein.Under the condition of treatment P1, the total starch content and its components content of treatment W2 was higher than that of treatment W0 and W1. At the base of treatment W2, more irrigation rate decreased the ratio of amylopectin to amylose significantly. Compared with treatment P0, phosphorus application increased the starch content, and had no significant effect on the ratio of amylopectin to amylose. The difference between treatment P1 and P2 was not significantly.The grain yield of treatment W2 was higher than that of treatment W0 and W1 under the condition of treatment P1. At the base of treatment W2, more irrigation rate did not increase grain yield, and it decreased the water use efficiency significantly. Phosphorus application improved the grain yield and water use efficiency significantly, but there was no significant difference between grain yield of treatment P1 and P2. The water use efficiency of treatment P2W2 decreased significantly.