The effect of nitrogen fertilization on root distribution of winter wheat

摘要

The effect of nitrogen fertilization on root length (RL) distribution of winter wheat (Triticum aestivum L.) was investigated. The study was conducted in Prague-Ruzyne on clay loam Chernozemic soil in the years 1996–2003. Two (N0, N1) and three (N0, N1, N2) treatments, unfertilized (N0), fertilized with 100 kg (N1) and 200 kg N/ha (N2) were studied in 1996–2000 and 2001–2003, respectively. Nitrogen rate 100 kg/ha had no effect on RL in soil layers (P 0.1) in years 1996–2000 and 2002–2003 and there was not significant interaction between N treatment and soil layer except for year 1998 (P 0.01). Nitrogen fertilization affected RL distribution significantly (P = 0.013) only in 2001 due to reduction of root growth in subsoil layers in treatment N2 (200 kg N/ha) in comparison with N0 and N1. The effect of N fertilization on total RL in rooted soil volume was insignificant. There was a significant effect of year on total RL (P 0.01) but not of interaction of year and N treatment. Roots reached, with the exception of two years, the depth between 100 and 130 cm. Nitrogen fertilization (N1) had no effect (P = 0.59) on rooting depth (RD) in years 1996–2000 but there was a significant effect of interaction between year and N fertilization on RD (P  0.01). In the second experimental series (2001–2003) N fertilization rate 200 kg N/ha significantly reduced maximum RD (P 0.01) in comparison with N0 and N1. The year had highly significant effect on RD.