Details

Autor(en) / Beteiligte

• Amossé, Camille
• Jeuffroy, Marie-Hélène
• Mary, Bruno
• David, Christophe

Titel

Contribution of relay intercropping with legume cover crops on nitrogen dynamics in organic grain systems

Ist Teil von

• Nutrient cycling in agroecosystems, 2014, Vol.98 (1), p.1-14

Ort / Verlag

Dordrecht: Springer-Verlag

Erscheinungsjahr

2014

Quelle

SpringerLink

Beschreibungen/Notizen

• Nitrogen (N) management is a key issue in livestock-free organic grain systems. Relay intercropping with a legume cover crop can be a useful technique for improving N availability when two cash crops are grown successively. We evaluated the benefits of four relay intercropped legumes (Medicago lupulina, Medicago sativa, Trifolium pratense and Trifolium repens) on N dynamics and their contribution to the associated and subsequent cash crops in six fields of organic farms located in South-East France. None of the relay intercropped legumes affected the N uptake of the associated winter wheat but all significantly increased the N uptake of the succeeding spring crop, either maize or spring wheat. The improvement of the N nutrition of the subsequent maize crop induced a 30 % increase in grain yield. All relay intercropped legumes enriched the soil–plant system in N through symbiotic fixation. From 71 to 96 % of the N contained in the shoots of the legumes in late autumn was derived from the atmosphere (Ndfa) and varied between 38 and 67 kg Ndfa ha⁻¹. Even if the cover crop is expected to limit N leaching during wintertime, the presence of relay intercropped legumes had no significant effect on N leaching during winter compared to the control.