No-till and nitrogen fertilizer reduction improve nitrogen translocation and productivity of spring wheat (Triticum aestivum L.) via promotion of plant transpiration

Abstract

Excessive nitrogen (N) fertilizer has threatened the survivability and sustainability of agriculture. Improving N productivity is promising to address the above issue. Therefore, the field experiment, which investigated the effect of no-till and N fertilizer reduction on water use and N productivity of spring wheat (Triticum aestivum L.), was conducted at Wuwei experimental station in northwestern China. There were two tillage practices (conventional tillage, CT; and no-till with previous plastic film mulching, NT) and three N fertilizer rates (135 kg N ha–1, N1; 180 kg N ha–1, N2; and 225 kg N ha–1, N3). The results showed that NT lowered soil evaporation (SE) by 22.4% while increasing the ratio of transpiration to evapotranspiration (T/ET) by 13.6%, compared with CT. In addition, NT improved the total N accumulation by 11.5% and enhanced N translocation (NT) quantity, rate, and contribution by a range of 6.2–23.3%. Ultimately, NT increased grain yield (GY), N partial factor productivity, and N harvest index by 13.4, 13.1, and 26.0%, respectively. Overall, N1 increased SE (13.6%) but decreased T/ET (6.1%) compared with N3. While, N2 enhanced NT quantity, rate, and contribution by a range of 6.0–15.2%. With the integration of NT, N2 achieved the same level of GY and N harvest index as N3 and promoted N partial factor productivity by 11.7%. The significant positive correlation of NT relative to T/ET and GY indicated that improving T/ET was essential for achieving higher NT. Therefore, we concluded that no-till coupled with N fertilizer rate at 180 kg N ha–1 was a preferable management option to boost the N productivity of spring wheat in arid areas.

Grain yield and interspecific competition in an oat-common vetch intercropping system at varying sowing density

“…Previous studies have shown that intercropping oats with common vetch significantly increase photosynthetically active radiation interception by oats, while decreasing interception by common vetch, thereby enhancing the overall light use efficiency of the intercropping system (Li et al, 2014). However, overcrowded plant populations exacerbate intraspecies competition, worsen canopy conditions, and reduce individual photosynthetic capacity, resulting in decreased grain yield per plant (Fan et al, 2022). Intercropping oats with common vetch reduced the common vetch grain yield by 1.51-13.77%, which indicating that the yield increase in oats comes at the cost of reduced common vetch yield.…”