Stalk yield and technological attributes of planted cane as related to nitrogen fertilization

Abstract

A still unclear question related to sugarcane cropping refers to the low response of the planted cane to nitrogen fertilization. Two experiments were carried out in areas under a Typic Hapludox, located in Pirassununga, São Paulo State, Brazil, and an Arenic Kandiudult, located in Jaboticabal, São Paulo State, Brazil, with the objective to evaluate planted cane response to nitrogen fertilization at planting. The experimental design was organized as random blocks and treatments consisted of three N rates (40, 80, and 120 kg ha -1 Nurea) and a control without N. Nitrogen fertilizers were applied to the bottom of the planting furrow and then incorporated into the soil. During the maximum growth stage, +1 leaf samples were collected from all experimental plots to evaluate the crop nutritional status. In the Pirassununga experiment, N fertilization at planting increased N, K, Mg, and S contents in the leaves and increased the stalk yield, without effect in the technological attributes. Conversely, no stalk yield response was observed at the Jaboticabal experiment, but N fertilization benefited the stalk technological attributes. The N rates increased the sugar yield per hectare in both experiments. The highest margin of agricultural contribution was obtained at the rate of 40 kg ha -1 N. Key words: Saccharum spp., nitrogen, urea Produção de colmos e atributos tecnológicos da cana planta relacionados com a adubação nitrogenada RESUMO: Uma questão não esclarecida na cultura da cana-de-açúcar se refere à baixa resposta da cana planta à adubação nitrogenada de plantio. Nesse sentido, foram desenvolvidos dois experimentos em áreas cultivadas sobre um Latossolo Vermelho-Amarelo Distrófico (Pirassununga, SP) e um Latossolo Vermelho Distrófico (Jaboticabal, SP), com objetivo de avaliar a resposta da cana planta a adubação nitrogenada de plantio. O delineamento experimental foi em blocos ao acaso, e os tratamentos foram três doses de N (40, 80 e 120 kg ha -1 na forma de uréia) mais um tratamento controle sem adição de N. Os fertilizantes nitrogenados foram aplicados no fundo de sulco de plantio e incorporados ao solo. Durante a fase de máximo crescimento da cultura, foram coletadas amostras de folhas +1 em todas as parcelas experimentais para a determinação do estado nutricional. Em Pirassununga, a adubação nitrogenada de plantio aumentou as concentrações de N, K, Mg e S nas folhas diagnósticas e a produção de colmos, sem apresentar efeito nos atributos tecnológicos. Por outro lado, em Jaboticabal não houve resposta em produtividade, mas houve efeito nos atributos tecnológicos. Obtiveram-se incrementos na produção de açúcar por hectare em ambas as áreas em função da fertilização nitrogenada. A maior margem de contribuição agrícola foi obtida com a dose de 40 kg ha -1 de N.

Contribution of nitrogen from sugarcane harvest residues and urea for crop nutrition

“…The amount of N-urea recovered by plant cane was 24.7 kg ha -1 , equivalent to 31 % of N rate initially applied. Those results were consistent with Franco et al (2010) which observed recovery of 28 % of N-urea by the plant cane for the average of two other sites in the Sao Paulo State using the same variety, N source and rate (80 kg of N ha -1 ). After plant cane, the recovery of N-urea applied at planting remained constant as (5; 4; and 3 % relative to first, second and third ratoons, respectively).…”

Assessment of sugarcane trash for agronomic and energy purposes in Brazil

“…The percentage of tops dry matter in our study was slightly higher than those observed by Franco et al (2010) with SP81-3250 in plant cane experiments in which the proportion of tops were in the range of 30 to 35 %. The amounts of trash produced did not vary among the eight sugarcane varieties as also found in the studies with post harvest residues of sugarcane in Brazil (Gava et al, Sci.…”

“…Regardless of the point of view of trash preservation or energy generation, all estimation have been done based just on the amount of crop residues, without taking into account the biomass composition. Sugarcane trash is a heterogeneous material formed by tops and dry leaves, which presents quite different physical-chemical composition (Franco et al, 2008;Franco et al, 2010).…”

Yield of sugarcane submitted to nitrogen fertilization and water depths by subsurface drip irrigation

“…The fact that there was no effect of N application, especially in the plant cane cycle, was possibly due to the high content of organic matter in the soil used in the study (Table 1). The response of the plant cane to N is little expressive and normally occurs at low doses (Franco et al, 2010;Fortes et al, 2013).…”

“…Nitrogen (N) fertilization can also promote yield increment in the plant cane cycle (Franco et al, 2010;Fortes et al, 2013); however, the responses to N application are still controversial. Localized irrigation, therefore, may present itself as an alternative, in which water and fertilizers are simultaneously applied through the drip system, promoting reduction in the consumption of water and fertilizers, which may result in higher sugarcane productions (Esperancini et al, 2015).…”