Efeito residual de fontes de fósforo nos atributos químicos do solo, nutrição e produtividade de biomassa da cana-de-açúcar

Abstract

RESUMOEm regiões de clima tropical o efeito residual da fonte de adubo fosfatado é de importância crucial. Objetivou-se avaliar os efeitos da aplicação de fontes de P nos atributos químicos do solo, nutrição e produtividade da cana-de-açúcar durante a cana planta e a primeira e segunda soqueiras. Foram aplicadas, no sulco de plantio, as fontes de P, superfosfato triplo, fosfato de Arad, farinha de ossos (100 kg ha -1 de P 2 O 5 total) e um controle, sem P, nas variedades de cana-de-açúcar IAC86-2480 e SP79-1011. Utilizou-se o delineamento de blocos casualizados em esquema fatorial 4 x 2, com quatro repetições. O trabalho foi realizado no município de Alta Floresta-MT, Brasil, em Latossolo Vermelho Amarelo distrófico. Após cada corte foi avaliado, no solo, o teor de P, Ca e pH. Na planta avaliaram-se a produtividade de fitomassa verde, de matéria seca da parte aérea, a concentração de P na biomassa coletada, a exportação de P e a eficiência agronômica das fontes de P. A farinha de ossos apresentou maior eficiência agronômica, proporcionou maior acúmulo e exportação de P pela cultura, maior teor de Ca e P disponível no solo e aumento do pH. O fosfato natural reativo de Arad aumentou sua eficiência agronômica entre os ciclos de cultivo.Palavras-chave: adubação fosfatada, eficiência agronômica, farinha de ossos, Saccharum spp. Residual effect of phosphorus sources in soil chemical properties, nutrition and biomass productivity of sugarcane ABSTRACTIn tropical regions, the residual effect of phosphate fertilizer source is of crucial importance. This study aimed to evaluate the effects of application of P sources in chemical properties of soil, nutrition and productivity of sugarcane plant and during the first and second ratoon. The sources of P applied in furrows at planting were, triple superphosphate, Arad phosphate, bone meal (100 kg ha -1 P 2 O 5 total) and a control without P, the varieties of sugarcane studied were IAC86-2480 and SP79-1011. A randomized block design in a 4 x 2 factorial was used, with four replications. The study was conducted in the municipality of Alta Floresta-MT, Brazil, in Typic Hapludox. After each cutting, in soil P content, pH and Ca were evaluated. In the plant, the production of green and dry matter of shoots, the concentration of P in the biomass harvested, the export of P and agronomic efficiency of the sources of P were determined. The bone meal had a higher agronomic efficiency resulted in greater accumulation and export of P by crop, higher content of available Ca and P and increase soil pH. The Arad reactive phosphate increased its agronomic efficiency between crop cycles.

Inoculation With Growth-Promoting Bacteria Associated With the Reduction of Phosphate Fertilization in Sugarcane

“…Albuquerque et al (2016) described that application of P as triple superphosphate up to 100 kg P 2 O 5 ha −1 in the furrow increases the yield of cane variety RB92579. Application of P in the furrow as triple superphosphate (at the rate of 100 kg P 2 O 5 ha −1 ) increased the yield of sugarcane by 34% in comparison of control (Caione et al, 2013). Calheiros et al (2012) performed experiment with same variety (RB92579) under different phosphate fertilizer and observed that greater stalk yield (133,000 kg ha −1 ) was recorded with application of 90 kg P 2 O 5 ha −1 .…”

Agro-industrial quality of plant cane, first and second ratoon in sugarcane varieties

“…Phosphorus is a macronutrient that has great importance in the growth and development of plants, since it participates in the structural composition of macromolecules, such as nucleic acids, phospholipids and adenosine triphosphate. In sugarcane, P plays a key role in metabolism, particularly in the formation of proteins, cell division, photosynthesis, energy storage, splitting of sugars, respiration and energy supply from ATP and formation of sucrose (Calheiros et al, 2012;Caione et al, 2013).…”

Nutrient Contents in Sugarcane Biomass in the First Regrowth Cycle

“…Various studies have shown that P the macronutrient least required by sugarcane (Benett et al, 2013;Rossato et al, 2016), although it is one of the elements that has most limited the cultivation of sugarcane in the tropics (Caione et al, 2013;Sousa et al, 2013;Simões Neto et al, 2015;Albuquerque et al, 2016). This fact is associated to the complex phosphorus dynamics in tropical soils, where there is predominance of 1:1 clays and iron and aluminum oxyhydroxides, which have high P adsorption capacity, promoting P fixation and reducing the efficiency of phosphate fertilization (Sanchez & Uehara, 1980).…”