To determine the effects of nitrogen reduction combined with film mulching measures on the yield composition and the utilization efficiency of water and fertilizer of winter wheat in the Loess Plateau

and to provide theoretical basis for reducing the application of nitrogen fertilizer and increasing the yield of winter wheat in dry land

in 2013-2018

experiment was conducted in winter wheat growing region of dry highland in Southern Shanxi. In the experiment

four treatment were set up

which were farmer pattern

monitoring fertilization

monitoring fertilization plus ridge mulching-furrow planting and monitoring fertilization plus whole field filming with soil covering and hole-seeding. The yield components

soil moisture and the utilization efficiency of nitrogen

phosphorus and potassium fertilizer were analyzed under the condition of reducing nitrogen and mulching for five consecutive years. The results showed that: (1) Compared with farmer pattern

total nitrogen application in the monitoring fertilization treatments decreased by 46.9%

and under the condition of balanced application of phosphorus and potassium fertilizer

the average annual grain yield

biological yield and panicle number per hectare of winter wheat increased by 4.4%

4.0% and 4.3%

respectively

the nitrogen harvest index and the partial productivity of nitrogen fertilizer increased by 4.3% and 120.3%

respectively. At the same time

the uptake of phosphorus and potassium by above ground part of winter wheat was promoted. (2) On the basis of monitoring fertilization

plastic film mulching planting increased water use efficiency and water consumption in growth period by 13.8%~23.9% and 7.1%~10.1%

respectively. At the same time

the harvest index of nitrogen fertilizer increased by 1.7%~3.5%

the partial productivity increased by 21.7%~41.4%

the physiological efficiency reduced by 8.7%~16.8%

and the partial productivity of phosphorus fertilizer and potassium fertilizer increased by 22.4%~39.2% and 19.3%~37.1%

respectively. Good water and fertilizer regulation effect of plastic film mulching planting increased the grain yield

the biological yield

the hectares ears and the 1000-grain weight by 21.0%

39.2%

18.2% and 4.7% in the treatment of ridge mulching-furrow planting

respectively

and by 23.5%

40.3%

27.6% and 7.0% in the treatment of whole field filming with soil covering and hole-seeding

respectively. Therefore

in order to increase wheat yield and fertilizer efficiency

the combination of the nitrogen reduction and control fertilization technology and the ground film covering measures can be applied in the planting area of the Loess Plateau.