Abstract

AREVALO-GALARZA, G.; HERNANDEZ-MENDOZA, T. M.; SALCEDO-PEREZ, E.  and  GALVIS-SPINOLA, A.. APPLICATION OF SYNTHETIC FERTILIZERS OR GREEN MANURE AND THEIR EFFECT ON THE AMOUNT OF RESIDUAL NITRATE IN SOIL. Rev. Chapingo ser. cienc. for. ambient [online]. 2007, vol.13, n.2, pp.85-90. ISSN 2007-4018.

The application of nitrogen fertilizers has the purpose to complete soil nitrogen supply to satisfied the crop demands; however, the inappropriate use of these inputs increase the quantity of residual nitrate in soil (Nr) and the risk of its posterior leaching, not being an issue if the fertilizers are synthetic (FS) or organic. The goal is to compare the effect of fertilization over Nr an essay of response to application of nitrogen was made, considering broccoli as crop indicator for its high demand in this nutrient. The elements were FS or green manure, this last applied on transplantation time (AV1) or fifteen days before the same (AV2). The broccoli response was quadratic (300 kg N·ha-1 as optimums physiological rate) with maximum yield of 1.94, 1.55 and 1.31 kg·plant-1 for FS, AV1 and AV2, respectively. The FS release less Nr, followed by AV1 and AV2, so we conclude that if organic fertilizers are not applied on time the Nr will increase, with the subsequent risk of leaching and water table pollution.

Keywords : leaching; mineralization; broccoli.