科研之友
微信
新浪微博
Facebook
分享链接
摘要
A field experiment was conducted to examine the effects of different depths of nitrogen (N) fertiliser placements on N accumulation, remobilisation and NO3--N content in soil of rainfed wheat. Nitrogen was applied on the surface (D-1) and in the 10 cm (D-2), 20 cm (D-3) and 30 cm (D-4) soil layers from 2010 to 2012. Compared with D-1 and D-2, D-3 and D-4 treatments obtained significant higher N distribution amounts in grain and N accumulation amounts at maturity. D-3 and D-4 treatments increased the N accumulation amount of vegetative organs at anthesis and at maturity. D-3 treatment resulted in significantly higher N translocation amounts from vegetative organs to grains compared with D-1 and D-2 treatments and had no significant difference with D-4 treatment. Compared with the D-1 and D-2, D-3 and D-4 treatments obtained significant higher NO3--N contents in the 20 cm to 120 cm soil layer at anthesis from 2011 to 2012. However, D3 treatment showed no significant differences with D-1 and D-2 treatments at maturity in terms of the NO3--N contents in the 40 cm to 100 cm soil layer. D-4 treatment produced the highest NO3--N contents in the 40 cm to 140 cm soil layer. Grain yield, N uptake efficiency, apparent N recovery efficiency, N agronomic efficiency and N partial factor productivity were significantly increased by D-3 and D-4 treatments. These results suggest that the D3 treatment facilitates the best wheat production and highest efficiency among all treatments.
