Dry matter and qualitative characteristics of alfalfa as affected by harvest times and soil water content

The best trade-off between quantity and quality in forage crops is one the most important targets of the agronomic research, since quantitative and qualitative traits are generally inversely correlated. With the aim of exploring the effect of harvest time (early and late), soil water content (irrigated and rainfed) and variety (Equipe, Europe and Midi) on duration, yield and quality of alfalfa, a four year trial was carried out in a Mediterranean environment. Early cut resulted in a reduction of forage yield (12%) with a faster reduction of longevity, but with a higher quality characteristics in terms of protein (20.2%) and fibre (23.1%) compared to the late cut (18.0 and 25.9%, respectively for protein and fibre). Dry treatment led to a limited reduction of yield and quality traits, suggesting alfalfa is a potential forage resource for the improvement of hilly areas of Mediterranean environment. The tested varieties show all a good regrowth capability allowing three, sometimes four, cut per year. The obtained results pointed out that the combination of early and late harvest times would allow a better distribution of the forage production between the months of June and September as well as a fair useful forage regrowth during the months of October and November.