An adaptive spacing of root‐zone hole fertilization to improve production and fertilizer utilization of rapeseed

Abstract BACKGROUND Root‐zone hole fertilization has a positive impact on enhancing crop production and fertilization efficiency. However, a suitable spacing for hole fertilization in rapeseed cultivation is unclear. To explore an adaptive hole spacing for improving rapeseed yield and fertilization efficiency, field experiments were conducted. Four spacings of hole fertilization were designed: 10 (FD10), 20 (FD20), 30 (FD30) and 40 cm (FD40), using no fertilization (F0) and deep‐banded placement of fertilizer (DBP) as controls. The burial depth was 10 cm for FD and DBP treatments. RESULTS Compared to DBP, hole fertilization impacted soil microenvironment, crop growth and yield components, resulting in a significant increase of 28.4% in seed yield and 25.6% in oil yield. Seed yield in FD20 (4345.43 kg ha −1 ) increased by 4.3%, 9.4% and 15.1% compared to FD10, FD30 and FD40, respectively. Fertilizer partial factor productivity under FD20 was 4.2%, 8.6% and 13.9% greater than FD10, FD30 and FD40, respectively; whereas the increase for agronomic efficiency was 6.0%, 12.7% and 21.0%, and the increase for N recovery efficiency was 39.5%, 52.5% and 62.9%, respectively. CONCLUSION Fertilization with a hole spacing of 17 cm is a promising practice to maintain high production and fertilization efficiency when cultivating rapeseed. These results provide a theoretical foundation and scientific basis for improving rapeseed productivity and fertilizer utilization. © 2024 Society of Chemical Industry.