Mechanical resistance of wheat to stem breakage in the late growth period considering mineral nitrogen and organic fertilisation

Abstract

In a long-term field trial IOSDV at Jable near Ljubljana (SLO) the impact of mechanical resistance of wheat stem to breakage and its dependency of N fertilisation rate and organic fertilisation were examined. The investigation was undertaken at the beginning of the waxy growth stage (EC 81/82). Results confirmed that organic fertilisation has a moderate impact on the N-content (mg N g⁻¹ DM) in wheat stem and on the bending moment (M) at stem breakage. The mechanical resistance of wheat stem to break was the strongest (M ≈ 0.1 Nm) at low mineral N fertilisation (65 kg ha⁻¹), while at the variants without mineral N fertilisation, bending moment was the lowest (M ≈ 0.02–0.03 Nm). N-content in the stem increased exponentially to the highest N fertilisation step (195 kg ha⁻¹), however there is not enough evidence to show that concentration of N in stem significantly effected bending moment at stem breakage.

Keywords:

• long-term field trial
• wheat stem
• bending moment
• N fertilisation rate
• N-content
• cropping system