Ammonium sulphate on maize crops under no tillage

Abstract

The objectives of this work were to evaluate the management of N and S (as ammonium sulphate) fertilization under notillage system on the components of maize productivity and on N and S accumulation in the crop, as well as to evaluate the minimum value of the Nitrogen Sufficiency Index (NSI 0.95) as an indicator for side dressing requirements. The experiment had a completely randomized block design with six treatments and four replications carried out in Red Latosol dystrophic soil (Hapludox), in Campo Mourão, Paraná State, where the following treatments in summer growth maize were applied: T1-120 kg ha -1 N in seeding; T2-120 kg ha -1 N in side dressing; T3-40 kg ha -1 N in seeding and 80 kg ha -1 N in side dressing; T4-30 kg ha -1 N in seeding and 90 kg ha -1 N in side dressing, monitored by a chlorophyll meter using the Nitrogen Sufficiency Index (NSI); T5-120 kg ha -1 N anticipated in wheat seeding; T6-without nitrogen fertilization. NSI was determined by the relationship between the leaf chlorophyll index (ICF) average of T4 plants and that one in the plot fertilized with 120 kg ha -1 N at the maize seed sowing (T1). During two years, ammonium sulphate was applied to the maize crop after wheat under no tillage system. In the first year, with adequate rainfall, the maize yield was similar to the one in which the complete ammonium sulphate dose application was done in maize seeding and side dressing. The anticipated fertilization to wheat seed sowing resulted in maize yield without difference from the parceled form. In the second year, with irregular rainfall, all treatments with N were similar and they increased maize yield compared to that without N fertilization. NSI of 0.95 was not efficient to evaluate maize N requirements in side dressing, and resulted in lower maize yield. N was accumulated mainly in the grains unlike S that accumulated in the plant shoots; both were highly correlated to maize productivity.Key words: Zea mays, Triticum aestivum, fertilizer management, nitrogen, sulfur.Resposta à aplicação do sulfato de amônio na cultura do milho cultivado sob plantio direto ResumoOs objetivos do trabalho foram avaliar o manejo de adubação com N e S (como sulfato de amônio) nos componentes de produção do milho e no N e S acumulados pela cultura, assim como avaliar o valor mínimo de Índice de Suficiência em Nitrogênio (ISN=0,95), como um indicativo da necessidade da adubação em cobertura, em plantio direto. O delineamento experimental foi blocos casualizados com seis tratamentos e quatro repetições em Latossolo Vermelho distrófico (Hapludox), em Campo Mourão (PR), utilizando os tratamentos no milho: T1-N 120 kg ha -1 na semeadura; T2-120 kg ha -1 de N em cobertura; T3-40 kg ha -1 de N na semeadura 80 kg ha -1 de N em cobertura; T4-30 kg ha -1 de N na semeadura e 90 kg ha -1 N em cobertura, cuja necessidade foi monitorada pelo clorofilômetro, em função do Índice de Suficiência em Clorofila (ISC); T5-120 kg N ha -1 antecipado na semeadura do trigo; T6-controle, sem aplicação de N. A necessidade da ...

In vitro establishment and early development of barueiro (Dipteryx alata Vogel)

“…This fact elucidates the reason chlorophyll contents is greater in the MS media, which provides more nitrogen and favours higher chlorophyll synthesis. This finding is contrary to the statement of Silva et al (2012) that the chlorophyll concentration is correlated with the concentration of nitrogen in the plant, as well as crop productivity. Based on this principle, the chlorophyll index has been used not only during in vitro culture, but also in the management of fruit already installed in the field, such as citrus and pecan (HARDIN et al, 2012;SOUZA et al, 2011).…”

Effects of Varieties and Nitrogen Fertilizer on Yield and Yield Components of Maize on Farmers Field in Mid Altitude Areas of Western Ethiopia

“…All maize varieties were given higher N accumulation at full recommended nitrogen fertilizer application as compared to half recommended nitrogen application and without fertilizer N application. da Silva et al [48] found that grain N accumulation was higher in all treatments with ammonium sulphate fertilization. The N accumulation in plants and grains was in agreement with the reports by Zotarelli et al [50].…”

“…Similarly, Anbessa and Juskiw [7] found that biomass N yield was increased with the rate of N fertilizer. The correlation coefficients between maize productivity and N accumulated in shoots (leaves, corncobs, straws, and stems) were high [48]. Moser [46] found that maize varieties differed significantly in shoot N concentration and shoot N accumulation and shoot N concentration was increased with increased rate of nitrogen.…”

“…Moser [46] found that maize varieties differed significantly in shoot N concentration and shoot N accumulation and shoot N concentration was increased with increased rate of nitrogen. The average of N accumulation in shoots collected at harvesting was 69.7 ha −1 [48]. Total amount shoot N accumulation increased as the rate of nitrogen fertilizer increased [46].…”

Teor de clorofila e índice SPAD no abacaxizeiro cv. vitória em função da adubação nitrogenada

“…As leituras instantâneas de maneira não destrutiva de folhas, proporcionadas pelo clorofilômetro, apresentam-se como alternativa de indicação do teor de clorofila presente na folha da planta (KLOOSTER et al, 2012). O teor de clorofila correlaciona-se com a concentração de N na planta e, também, com a produtividade das culturas (SILVA et al,2012b). Em algumas frutíferas, como citros (SOUZA et al, 2011) e nogueira-pecã (HARDIN et al, 2012), o uso do índice SPAD tem-se mostrado adequado para auxiliar no manejo na adubação nitrogenada.…”