INFLUENCE DE LA FERTILISATION AZOTEE ET DE L’ECARTEMENT ENTRE LES RANGS DE CEREALES-ABRI RECOLTEES COMME FOURRAGE SUR L’ETABLISSEMENT DE LA LUZERNE

The effect of companion crop management on the establishment of alfalfa was evaluated. The studied variables included species of cereals, row spacing and seeding rate of companion crop, stage of maturity of the companion crop at harvest, and an additional nitrogen fertilizer application. The cereals were harvested as forage. In the year after the seeding year, the first yield of alfalfa was determined. In seven trials, forage yields of a pure stand of alfalfa were 3350 kg/ha in the first cut of the seeding year. These yields averaged 60% of forage yields obtained from the combination of alfalfa and companion crop. However, cereals substantially reduced the total digestible nutrients, crude protein and calcium contents of the forage as compared to the pure alfalfa. The additional 38 kg/ha of nitrogen at tillering provided an extra yield of 600 kg/ha. Row spacing had little or no effect on forage yield. Even though wider spacings has considerably reduced seeding rates increased spacing from 18 to 54 cm did ...