Production and levels of foliar nitrogen in rocket salad fertilized with controlled-release nitrogen fertilizers and urea

Abstract

Controlled-release nitrogen fertilizers enhance crop productivity and decrease nitrogen loss through volatilization and leaching. This study aimed at determining the effect of nitrogen treatments provided by controlled-release nitrogen fertilizers and urea. The following fertilizers were tested: 1 (agricultural urea), 2 (ammonium sulfonitrate + nitrification inhibitor, dimethylpyrazole phosphate (Entec 26®)),3 (urea + Kimberlit polymer (Kimcoat N®)) and 4 (urea + NBPT (Super N - Agrotain®)). Treatments corresponded to 0, 100, 200, 400 and 800 kg ha-1 of N with rocket salad grown inside a greenhouse, assessing the production of fresh and dry leaf mass as well as levels of foliar nitrogen. Doses of different controlled-release nitrogen fertilizers showed significant polynomial regressions for the production of rocket salad fresh leaf mass and levels of foliar nitrogen, whereby Entec 26® did not show significant polynomial regression, considering the last parameter evaluated. The production of rocket salad dry leaf mass did not display significant linear regressions. The maximal production of rocket salad fresh leaf mass was reached at doses of 600, 490, 765, and 462 kg ha-1 of N with the use of urea, Entec 26®, Kimcoat N® and Super N®, respectively.

Cultivation of lettuce fertilized with controlled-release nitrogen fertilizer and urea

“…The use of coated urea was not enough to prevent losses of N, probably because of the daily irrigation of the crop. These data were in contrast to those of Ratke et al, (2011), who found increased productivity with the use of slow release fertilizers on rocket salad. Urea and coated urea present N in the starch form, which is transformed in the soil into the ammonium form (NH 4 + ), by the action of an enzyme, known as urease.…”

Effects of hydrogel and nitrogen fertilization on the production of arugula in successive crops

“…Regarding fresh mass, there was a quadratic fit of the data to quadratic polynomial regressions with maximum values estimated at 179.8 and 132.9 kg N ha -1 for the SFM and RFM, respectively (Figure 2). Ratke et al (2011), working with N fertilization in the cultivation of arugula, found that the SFM increased quadratically with a maximum value of 600 kg ha -1 , which is greater than that obtained in the present study.…”

Yield and chlorophyll index in cabbage in function of enhanced-efficiency nitrogen fertilizers and urea

“…Pesquisas têm demonstrado que a ureia tratada com inibidor de urease ou revestida com polímeros maior eficiência de aproveitamento de N e maiores produções de planta, em função das reduções de perdas de N por volatilização (Watson et al, 2008;Scivittaro et al, 2010;Cobena et al, 2011). Entre essas, Ratke et al (2011) observaram que a produção de massa fresca de folhas de rúcula foi mais eficiente utilizando ureia revestida com polímeros (Kimcoat N) ou tratada com inibidor de urease (NBPT), em comparação a ureia comum. Resultados similares foram observados por Oliveira et al (2016), na cultura do milho fertilizado com ureia revestida por três polímeros.…”

“…A ureia, que responde por mais de 50% dos fertilizantes nitrogenados na agricultura brasileira (IFA, 2019), apresenta limitações quanto à aplicação superficial devido à possibilidade de perdas por volatilização de amônia (NH 3 ). O processo de volatilização envolve, inicialmente, a hidrólise da ureia por meio da urease, que é uma enzima extracelular produzida por bactérias, actinomicetos e fungos do solo ou, ainda originada de restos vegetais (Reynolds et al, 1985;Cantarella, 2007). Além das perdas por volatilização de amônia, há ainda, perdas decorrentes da lixiviação de nitrato (NO 3 -), que ocorre devido ao processo de nitrificação, onde há a oxidação de amônio (NH 4 + ) a nitrato (NO 3 -), pela ação de bactérias quimioautotróficas do solo que obtêm energia no processo (Cantarella, 2007).…”