versão impressa ISSN 0006-8705
NOBREGA, Sylvio de A. e FREIRE, E. S.. Experiments on methods of applying nitrogen to potatoes. Bragantia [online]. 1964, vol.23, n.unico, pp.351-364. ISSN 0006-8705. http://dx.doi.org/10.1590/S0006-87051964000100029.
Eleven experiments with potatoes were conducted in the State of São Paulo to compare, in the presence of PK, the effect of increasing rates of mineral nitrogen applied either exclusively in the planting furrows (usual method), or as top-dressing, the highest rate being also parceled out and applied in both manners. The study indicated that the application of the usual nitrogen dosis in the planting furrows gives satisfactory results only when followed by rainy weather; otherwise, it delays sprouting or reduces the stands. On the other hand, the application of the whole dosis as delayed top-dressing may result in nitrogen hunger by the plants during the period of the most active growing. Based on the observations made in the present and previous experiments, the authors therefore suggest the application of part of the dosis with PK by the side-placement method, the remaining part being top-dressed as soon as the first sprouts appear on the soil surface. When planting during the normally drier season, it should be more indicated to apply the supplementary part deeper than the side-placed part.