Fertilización foliar del frijol común (Phaseolus vulgaris L.): II. Efecto de la aplicación foliar del nitrógeno con y sin aplicación de nitrógeno al suelo

Rosolem, C.A; Machado, J.R; Balducci Junior, J.J; Hing, L.T.

Alternative title

Foliar fertilization of beans (Phaseolus vulgaris L.):II. Effects of nitrogen with and without topdressing

Adubaçao foliar do feijoeiro (Phaseolus vulgaris L.): II. Efeitos do nitrogenio com e sem cobertura nitrogenada.

Résumé

In two field experiments, the effects of nitrogen fertilizers applied in the soil and/or on the leaves on bean production were studied. The first experiment was conducted during the wet season and the second during the dry season. Nitrogen (32-0-0) was applied on the leaves on 5 levels (0, 12, 24, 36 and 48 l/ha divided into a applications (15, 30, 45 and 60 days from seedling emergence), in the presence or absence of 30 kg/ha of topdressed nitrogen. The topdressed nitrogen always increased bean production. In the wet season there was a small production increase due to foliar fertilization in the absence of topdressing, but in the dry season a tendency to quadratic reponse to foliar fertilization was noticed irrespective of topdressing. Nitrogen application on the soil (20 days from seedling emergence) caused an increase in number of pods per plant whilst the foliar fertilization with nitrogen in the absence of topdressing increased the thousand-grain weigth.