Biomass Production and Seed Yield in the Association of Sunflower (Helianthus annus L.) and Common Bean (Phaseolus vulgaris L.) as Affected by Nitrogen and Phosphorus

The study was carried out during the 2003 in Montecillo, state of Mexico, to determinate the effect of nitrogen (0, 40 and 80 kg N ha(-1)) and phosphorus (0, 30 and 60 kg P2O5 ha(-1)) on the crop of sunflower (cv. Victoria) and common bean (cv. Michoacan). With the supply of 80 kg N ha(-1) the biomass production and seed yield was increased in a 32% and 35%, respectively, in relation to the control treatment group. When 60 kg P2O5 ha(-1) were added, the production on dry matter and seed yield surpassed the control treatment in a 24% and 27% respectively. Although interaction nitrogen x phosphorus was not significant, a positive tendency existed according to the increased levels of nitrogen and phosphorus (80 - 60 - 00), reaching the most values in biomass production (2667.9 g m(-2)) and seed yield (644.6 g m(-2)), which surpassed the control treatment in 49% and 50%, respectively.