Improvement of Lucerne Cutting Management: The Relative Impact of Initial Organic Reserves, Cutting Height and Residual Leaf Area on Forage Yield

Improvement of Lucerne Cutting Management: The Relative Impact of Initial Organic Reserves, Cutting Height and Residual Leaf Area on Forage Yield

Less lucerne (Medicago sativa L.) is now grown because of difficulties arising from 2 interacting characteristics: productivity and stand persistence. Optimisation of these two parameters depends highly of the cutting management (cutting height and/or frequency) and of the taproot N reserves. For example, Avice et al. (1997) showed that lucerne shoot regrowth is relates closely to taproot soluble protein concentrations (especially vegetative storage protein: VSP). However, it is not known how stubble C-N reserves and/or residual leaf area (both depending of the cutting management) influence the contribution of taproot reserve-derived C-N supply to regrowing lucerne shoots after defoliation. This study aimed to estimate the role of stubble C/N reserves or residual leaf area (RLA) on the contribution of taproot N reserves to shoot regrowth of lucerne after cutting.