| Aims:This study aimed to study the law of nutrient uptake and water use of drip irrigated spring wheat, to provide a experimental basis for developingreasonable irrigation fertilization plan for high fertilizer and irrigation efficiency for drip irrigated wheat cultivation in arid area. Methods:The study was conducted in Agriculture Experiment Station of Shihezi University in 2013 to 2014. Soil texture is loam, Xinchun 6 spring wheat variety was used in the study. Field experiment was designed to study wheat nutrient under drip irrigation. The experiment is a three factors partial design, the dosage of N was 0, 210, 300, 390kg/hm2, P was 0, 60, 120kg/hm2, K was 0, 45, and 90kg/hm2). Nitrogen application pattern experiment was set to study N optimal split application method. The dosage of N was 300kg/hm2, the application pattern was(1) mainly applied in basal,(2) mainly applied in early growth period(3) mainly applied in late growth period. Irrigation experiment was conducted in 2014. The experiment is a split design. The main factor was irrigation method(flooding irrigation and drip irrigation), the secondary factor is irrigation volume(3000, 5250, 7500m3/hm2). Shoot biomass, shoot nutrient uptake, soil moisture, root morphology parameters was sampled and measured in different growth stages to determine the law of spring wheat nutrient uptake and water consumption.Result:(1)The highest yield under different NPK treatment was 7529 kg/hm2. NPK uptake in this yield were 307 kg/hm2, 59kg/hm2 and 407kg/hm2, N, P, K recovery rate was 46.63%, 17.05%, 58.62%.(2)The dynamic of N, P, K uptake can be fit by logistic curve, the peak of NPK uptake appears in 26-57 days after seedling emergence, or from shooting to heading stage. During this period wheat uptake NPK nutrient occupied the total nutrient uptake 66%-79%, 62%-69% and 66%-70%, respectively. With the increasing of fertilizer rate, the nutrient uptake rate and maximum uptake rate also increased, the beginning of quick uptake stage was move up and last for a longer time. The quick uptake stage of N appeared earlier than K, and P was the latest. NPK quick uptake stage lasted for around 24 d, 26 d and 21 d.(3)Drip irrigation maturity of nitrogen, phosphorus and potassium accumulation respectively higher 7%,, 9%, 2% of flood. With increasing irrigation amount, the distribution ratio of nutrients increase in the vegetative organs in particular to stem. Too large to reduce the proportional distribution of grain. Under drip irrigation nitrogen, phosphorus and potassium accumulation respectively higher flood4.66-5.37%,3.81-4.63%,1.02-1.59% in grain, Stem potassium accumulation lower of 4.19-4.72%.(4)Wheat yield increased with the increase of N input, while if surpass optimal point, yield decline with further N input. Grains per spike, unit spike number, grain weight was affected by N fertilization, spike number was most significantly affected by N application. P and K mainly affect wheat spike number and hence affect yield. The intense of yield increment by different fertilizer was order by N> P> K.(5)The optimal apparent water consumption for drip irrigated spring wheat was 548.17 mm for whole growth period, Drip irrigation water more than flooding 3.92-14.06 mm jointing and heading period was critical period of water demand for spring wheat. Water consumption order was heading stage> jointing> Flowering> tillering> Booting> filling> mature> seedling, Each growth period consumption mold coefficient by order of 7.53%, 15.3%, 22.11%, 9.83%, 15.53%, 17.45%, 8.96%, 3.28%.(6)Root length in drip irrigated spring wheat is greater than in flooding irrigation, in drip irrigation, root near the drip tape was shorter than far from the drip line. Both drought or over irrigation reduce root growth but optimal irrigation quota produced the longest root length. Root mean diameter was smaller in drip irrigation than in flooding irrigation, and high amount of irrigation result in small root diameter. Drought stress was beneficial for root surface area than over irrigation, but the biggest root surface appeared in optimal irrigation treatment.(7)The positive effect area of water and fertilizer for spring wheat fertilization was N < 319 kg / hm2 and irrigation number <5587m3 / hm2, N = 319 kg / hm2 and irrigation number =5587m3 / hm2 was the peak point for N input and irrigation. Additional inputs produce negative results. Water and fertilizer performance abide by law of diminishing, and the partial effect of the two factor was N > irrigation amount, Fertilizer performance was greater than irrigation effect if N>268kg/hm2, WD>4440m3/hm2. Conclusions:(1)The peak of NPK uptake appears in 26-57 days after seedling emergence, or from shooting to heading stage. The quick uptake stage of N appeared earlier than K, and P was the latest. The intense of yield increment by different fertilizer was order by N> P> K. Drip irrigation maturity of nitrogen, phosphorus and potassium accumulation respectively higher 7%,, 9%, 2% of flood. With increasing irrigation amount, the distribution ratio of nutrients increase in the vegetative organs in particular to stem. Too large to reduce the proportional distribution of grain. Under drip irrigation nitrogen, phosphorus and potassium accumulation respectively higher flood4.66-5.37%,3.81-4.63%,1.02-1.59% in grain, Stem potassium accumulation lower of 4.19-4.72%.(2)The optimal apparent water consumption for drip irrigated spring wheat was 548.17 mm for whole growth period,Drip irrigation water more than flooding 3.92-14.06 mm,jointing and heading period was critical period of water demand for spring wheat. Water consumption order was heading stage> jointing> Flowering> tillering> Booting> filling> mature> seedling.(3)The positive effect area of water and fertilizer for spring wheat fertilization was N < 319 kg / hm2 and irrigation number <5587m3 / hm2, Water and fertilizer performance abide by law of diminishing, and the partial effect of the two factor was N > irrigation amount, Fertilizer performance was greater than irrigation effect if N>268kg/hm2, WD>4440m3/hm2. |
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