| As a kind of modern technology, drip irrigation is widely recognized as a water-saving and efficient irrigation method. Study on irrigation conducted both at home and abroad mostly are on higher output crops like fruit trees, vegetables, cotton, melons and some others and has been promoted to large area. While researches on spring wheat drip irrigation is comparatively less. Through the comparison of physiological characteristics,water consumption,harvest yield and yield components of spring wheat growing under drip irrigation and conventional flood irrigation of field investigations and small area control test in 2008-2009 in north Xinjiang, the thesis analyses the effect of different water treatments on spring wheat growth,dry matter accumulation, yield components and water use efficiency, It discusses the characteristics of the water requirement and yield components. Through the research it draw the following conclusions:(1) the same soil layer 0-20cm Department, with different drip irrigation treatments the soil moisture is different too. Soil moisture content has a significant change before and after irrigation; 0-40cm layer of soil water content as a whole tended to be stable, of which the overall treatment showed as Wl treatment <W2 treatment<W3 treatment<W4 treatment; 40-60cm soil layer with a different distance from the drip soil water content did not change significantly, indicating profound changes in the soil for irrigation has little effect, and with the deepth of the soil reduce the water content change rate.(2) The evapotranspiration of drip irrigation wheat throughout the growth period was 545.94 mm, the average water consumption was 5.35 mm/d. Two breedes in different water conditions, the drip irrigation wheat of yield and water consumption showed a single peak curve, when water consumption raised to a certain extent, the yield instead lower; the WUE of different breedes of wheat in different irrigation treatments and drip irrigation wheat and flood irrigation wheat, W3 treatment was the highest, xinchun 6 was 10.39 kg/mm·hm2, flood irrigation treatment the WUE of xinchun 22 was 6.61 kg/mm·hm2; drip irrigation wheat of crop coefficient was 0.75 at sowing-jointing, jointing-Tassel up to 1.05, Tassel-milk reached to 1.09, in the milk-maturity reduced to 0.79.(3) The height of plants of low and high line appears a "wavy" trend under the same water treatment of W1, W2. The LAI of drip irrigation wheat and flood irrigation wheat showed a normal curve. With the increases of GDD, the LAI go up at first, then down. The SPAD value of drip treatment of wheat W1, W2 processing decreased from the beginning of anthesis; Pn value of treatment in W1, W2 processing shifts are:first line> second line> third line, W3 treatment maximum value of Pn is about ten days after flowering, then maintained a higher value; Tr value change is in the early and mid filling rising to 20 days after flowering, reached the maximum, then decreased rapidly; Cd value declines slowly withinn the 10 days after flowering to spend and decline rapidly after until maturity.(4)dry matter and the spike accumulation of spring wheat consistented with the typical "S" curve, while a parabola of quadratic function was detected in the change of leaf and stem during growth. The growth degree days of effective dry matter accumulation (GDDEDMA) of spring wheat watered with drip irrigation was 1180.14℃, and the growth degree days of high-speed dry matter accumulation (GDDHDMA) was 670.68℃. The growth degree days (GDD) of spring wheat watered with drip irrigation was 83.38℃lower, while wheat production quantity during growth degree days (PEGDD) was 2.42 (kg/hm2)/℃higher than flood irrigation when spring wheat reach the highest dry matter accumulation rate. When compared with flood irrigation, spring wheat in drip irrigation with higher biomass accumulation, leaf and spike allocation rate, leaf and spike output and transaction rate. (5) the yields between different water treatments differ significantly between 1%, As effected by the different amount of irrigation, the yields under the same water treatment between different lines differ too. Different water treatments on the impact of different wheat spike length, spikelet number and seed sterile spikelets were significance; sterile spikelet number with distance farther drip irrigation belt, the more sterile spikelets; the maximum number of spike grains were 48, the minimum is 11.7; grain weight of drip irrigation wheat is heavier than wheat of flood irrigation wheat, of which the 1000-grain weight was 51.8g. |
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