减氮结合不同覆盖对冬小麦产量、 水氮利用及根系的影响.

[Objective] The effects of nitrogen reduction combined with different mulching methods on water-saving and yield-increasing of winter wheat were studied in dry land of Loess Plateau, to explore dry land winter wheat yielding under reduced nitrogen binding overlay mode, efficient and environmentally friendly cultivation fertilization techniques. [Methods] A field test was conducted in Yongshou county Shaanxi province in 2014 -2016 years, to determine the effects of nitrogen reduction and different mulching methods on winter wheat yield, water use efficiency and root growth. [Result] Under the nitrogen application rate of 150 kg, hm-2, compared with the household nitrogen reduction, the physiological efficiency of nitrogen fertilizer of ridge mulching and furrow sowing increased by 12% in the fust year, water consumption increased by 7% in second year. The yield and water storage before sowing and physiological efficiency of nitrogen fertilizer of whole film mulching increased by 15%, 15 % and 16 % in the first year, while increasing by 12%, 10% and 35% in second year. The yield and water storage before sowing of straw mulching increased by 9 % and 16 % in the first year, water use efficiency and above-ground nitrogen uptake increased by 12 % and 17 % in the second year respectively. The total root length of ridge mulching and furrow sowing and whole film mulching decreased 35 % and 26 % in the first year. The total dry weight and total root length of straw mulching decreased 63 % and 43 % in the first year, while decreasing by 41 %, 10 % and 17 % in second year. [Conclusion] Compared with the farmer model, there was no significant effect of nitrogen reduction on yield, water use and root growth of winter wheat compared with farmer model. Under the nitrogen application rate of 150 kg / hm-2. Compared with the farmer nitrogen reduction, the ridge mulching and furrow sowing increased the nitrogen fertilizer physiological efficiency and water consumption. The whole film mulching significantly increased winter wheat yield, water storage and water use efficiency, and the nitrogen absorption and utilization efficiency can be improved. Straw mulching significantly increased water storage and water use efficiency before sowing, thereby increasing winter wheat yield. Reducing total root weight and total root length of dry winter wheat by ridge mulching and furrow sowing, whole film mulching and straw mulching. Therefore, the nitrogen reduction combined with different cover measures is an important measure to achieve efficiency of dry land winter wheat yield. [ABSTRACT FROM AUTHOR]