Nitrogen sidedressing and molybdenum leaf application on irrigated common bean in cerrado soil/Nitrogenio em cobertura e molibdenio via foliar no feijoeiro irrigado cultivado em solo de cerrado

Nitrogen is the nutrient required in greatest quantities by the common bean, and even when that nutrient is properly supplied, the yield of common bean plant may be limited by molybdenum deficiency, due to molybdenum participation in nitrogen metabolism. The objective of this work was to evaluate the performance of the irrigated common bean (Phaseolus vulgaris L.), cultivar 'BRS Pontal', affected by nitrogen sidedressing and molybdenum leaf application, when grown in Typic Quartzipsamment, in Cassilandia, Mato Grosso do Sul State, Brazil. A randomized complete block design was used, in a 4 x 2 factorial array with four replications. Treatments were constituted by four doses of nitrogen (0, 30, 60 and 120 kg [ha.sup.-1]), using urea and by the absence or presence of molybdenum (80 g [ha.sup.-1]) sprayed on leaves, in the form of ammonium molybdate. The relative chlorophyll index in leaves of common bean was increased by nitrogen sidedressing and molybdenum leaf application. Nitrogen sidedressing fertilization increased common bean grain yield only when combined with molybdenum leaf supply. Leaf application of 80 g [ha.sup.-1] of molybdenum increased N use efficiency by common bean.