Effects of the application of sewage sludge and fowl manure on soils of Paraná state in maize plants (Zea mays L.) as a macro-nutrients source

The potential of two organic residues as sources of macro-nutrients in three types of soils of the third plateau of Paraná state was studied. Treatment consisted of a dose (38 t.ha-1) of fowl manure and sewage sludge neutralized by a 3:1 (CaO+MgO) mixture. Fowl manure was kept in natura. Maize (Zea mays L.)was reference plant. After 30 days of seeding, the aerial parts of the plants were cut. They were dried at 70 0C till constant weight was obtained, then weighted and ground. Analyses were undertaken after nitric-perchloric digestion of the samples. Macro-nutrient levels in soils and in plants were determined by atomic absorption spectrometry, flame technique. Results showed that production of dry matter was higher when fowl manure was used. Levels of macro-nutrients in Terra Roxa - TR were higher than those of Latossolo Vermelho Escuro - LE (Deep Red Latisol) and Podzólico Vermelho - PV (Red Podzolic), soils respectively. In aerial parts of maize plants collected in the soils treated with organic residues the concentrations of K, Ca, Mg, S and P were higher than those without treatment. The sewage sludge caused highest relation in Ca:Mg.<br>Em casa de vegetação avaliou-se a potencialidade de dois resíduos orgânicos como fonte de macronutrientes em três solos do terceiro Planalto do Estado do Paraná. Os tratamentos consistiram numa dose (38 t.ha.-1) de esterco de ave e de lodo de esgoto neutralizado, permanecendo o esterco de ave in natura. O milho safrinha (Zea mays L.) foi utilizado como planta teste. Após 30 dias da semeadura, cortou-se a parte aérea das plantas. Estas, foram secadas a peso constante, moídas e analisadas após digestão nitro-perclórica. Os teores de macronutrientes nos solos e nas plantas foram determinados por espectrometria de absorção atômica. Os resultados mostraram que a produção de material seco foi superior com a cama de ave. Os teores de macronutrientes no solo TR (Terra Roxa) foram superiores aos dos solos LE (Latossolo Vermelho Escuro) e PV (Podzólico Vermelho), respectivamente. Na parte aérea das plantas de milho apenas as concentrações dos elementos K, Ca, Mg, S, P foram estatisticamente diferentes. O lodo de esgoto 60% foi responsável pela maior relação Ca:Mg

Effects of the application of sewage sludge and petrochemical residue in maize culture as source of micro-nutrients on soils of Paraná state

An evaluation of the potential of two organic residues as source of micro-nutrients in three soils of Paraná state was studied. Treatments consisted of one dose (38 t.ha-1) of sewage sludge and residue of purified used motor oil both neutralized with CaO+MgO mixture in 3:1 rate. Maize (Zea mays L.) was used as reference plant. After 30 days of seeding, the aerial parts of the plants were cut. They were dried at 70&ordm;C till constant weight and ground. Analysis was undertaken after nitric-perchloric digestion. Micro-nutrients levels in the soils and in the aerial parts of the plants were determined by atomic absorption spectrometry. The results showed a production of the aerial parts of the plants treated with sewage sludge higher than those in other treatments. The micro-nutrients in Terra Roxa - TR were higher than those of Latossolo Vervelho Escuro - LE (Deep Red Latisol) and Podzólico Vermelho - PV (Red Podzolic) soils, respectively. In the aerial part of the maize plants in treated soils concentrations of micro-nutrients Cu, Fe, Mn and Zn were higher than those without treatment