Knowledge of the nutrient uptake by crops at different stages of growth may provide the basis for rational application of fertilizers, which may lead to reduced production costs and improved use of fertilizers by plants. Based on this knowledge, we conducted this study to determine the biomass and nutrient accumulation curve of the onion cultivar Bella Vista in a system of transplanted seedlings. The experiment was carried out in Ituporanga-SC, Brazil, by using a randomized block design with three replicates. Eleven plant collections were carried out throughout the crop cycle. The variables evaluated included plant length; total dry biomass of leaves, bulbs, and roots; and concentrations of macro- and micronutrients. The maximum dry biomass accumulation in the shoots and bulbs at 140 days after transplanting (DAT) was 4.26 and 27.41 mg per plant, respectively, which contributed to 13% and 85% of the whole plant dry biomass at the end of the cycle, respectively. Potassium (K, 521.6 mg) was accumulated in the largest quantity per plant, followed by nitrogen (N, 465.7 mg), calcium (Ca, 253.3 mg), sulfur (S, 109.0 mg), magnesium (Mg, 86.9 mg), and phosphorus (P, 76.5 mg). The micronutrient accumulation was as follows: iron (Fe, 6,227.5 µg), boron (B, 902.3 µg), zinc (Zn, 573.7 µg), manganese (Mn, 573.7 µg), and copper (Cu, 241.4 µg).

ABSTRACT:Nitrogen fertilization and an appropriate cutting thickness can result in firmer sod that can be handled in less time with greater turfgrass regrowth during the subsequent cycle.This experiment was conducted on a sod production farm located in Capela do Alto, in the state of Sao Paulo, Brazil. The soil was a dystrophic Rhodic Hapludox (Oxisol) with a medium texture.The experiment had two statistical designs; the initial design was randomized blocks with seven treatments and four replicates. Treatments were five doses of liquid organo-mineral fertilizer (OMF) corresponding to 0, 100, 200, 300 and 400 kg ha -1 of nitrogen (N) with supplementation of phosphorous (P) and potassium (K) as well as two control treatments -one with 300 kg ha-1 of N as OMF and the other with 300 kg ha -1 of N-urea + P and K. At harvest, the adopted design was a split-plot type with four replicates in a 7 × 3 factorial arrangement with seven treatments as the main plot and three sod cutting heights (9, 16 and 22 mm) as subplots. Nitrogen doses in the form of OMF influenced the percentage of ground cover (PGC) by turfgrass in both cycles.The N dose of 300 kg ha -1 formed the sod more quickly and provided the largest mass of roots and stolons and the highest sod tensile strength. The thinnest sod samples had faster regrowth and provided higher PGCs.

The history of sod production in Brazil is somewhat recent when compared with conventional agricultural crops. This review describes the beginning of sod production in Brazil and the introduction of Emerald grass, as well as the emergence of Sod Growers Associations, which coincides with the marked expansion of the sector. The grass species and cultivars grown in Brazil are also presented and the main characteristics described. The text also reports few data in sod production area in the country, providing an overview planting evolution and characteristics of the market.

The objective of this study was to evaluate the effect of nitrogen topdressing rates applied to an intercrop of maize (M) with paiaguás grass (G) and pigeonpea (P) on silage production and on the pasture development in the offseason. Treatments consisted of two simultaneous intercropping systems (M + G; and M + G + P) and four N topdressing rates (0, 80, 160, and 240 kg ha?1). The introduction of pigeonpea into the system and the increasing N rates provided gains in yield and silage quality. Pigeonpea responded to nitrogen fertilization by having good regrowth and good dry matter yields in the intercrop. For silage making, the N rates of 240 kg ha?1 N for M+G and 120 kg ha?1 for M+G+P can be recommended. Nitrogen rates promote an increase in the dry matter yield of the grass and of pigeonpea, resulting in improvements in the pasture during the offseason.

Objetivou-se com este trabalho avaliar a influência do gesso na taxa de cobertura verde do solo pela forragem e a exportação de nutrientes em função das doses aplicadas. O experimento foi conduzindo em campo nos anos de 2012 a 2014 na Fazenda Escola da Universidade Estadual de Goiás, Câmpus São Luís de Montes Belos/GO. O delineamento experimental utilizado foi o de blocos ao acaso, com seis tratamentos e quatro repetições. Os tratamentos foram constituídos por quatro doses de gesso (450, 900, 1800 e 3600 kg/ha) e mais dois tratamentos adicionais: um controle (sem gesso e adubação) e um tratamento que recebeu somente a adubação química. Os tratamentos com gesso também receberam a adição de fertilizantes. O gesso promoveu aumento da taxa de cobertura verde do solo pela forrageira, principalmente no período da seca. A ordem decrescente de extração para o capim-marandu, considerando extração máxima de cada nutriente, foi: K > N > Mg > Ca > P > S. Para uma produção média de 10 t/ha · ano do capim Marandu necessita-se de 146, 13, 179, 31, 32 e 14 kg/ha de N, P, K, Ca, Mg e S, respectivamente.

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The objective of this work was to evaluate the productivity and extraction of macronutrients by Urochloa brizantha cv. BRS Paiaguás (Syn. Brachiaria brizantha cv. BRS Paiaguás) single and intercropped with pigeon pea (Cajanus cajan cv. BRS Mandarim), subjected to four doses of nitrogen applied in topdressing (0, 80, 160 and 240 kg ha-1). The experiment was carried out in São Luís de Montes Belos, GO, in soil classified as dystrophic red latosol, under Cerrado conditions. Plant height and dry mass of pigeon pea, plant height, number of tillers, dry mass, and macronutrient extraction by Paiaguás palisadegrass were evaluated. Higher mass production was observed in the pasture intercropped with the legume, requiring a lower amount of N. Based on the results exposed, the cultivation of Paiaguás palisadegrass reaches higher productivity when intercropped with a legume such as pigeon pea, in addition to providing greater efficiency in the use of nutrients such as N, P and K. Nitrogen fertilization has a negative influence on the production of dry mass and height of pigeon pea plants.

The aim of this work was to increase the aerial part, biometry, and yield of achenes from sunflower plants on the effect of increasing doses of blood residue, as an alternative source of phosphorus (P), in a clayey-textured red Oxisol. The experimental design used was randomized blocks, with six treatments and four replications. The treatments consisted of five doses of blood residue (0, 6, 12, 24 and 48m3 ha-1) and a control treatment that received phosphate chemical fertilization, 80kg ha-1 of P2O5. The increasing doses of blood residue and chemical fertilization do not show disproportionality for P concentration in soil, leaf, plant height (PH), stem diameter (SD), chapter diameter (CD) and achene production. The analysis of the principal component (PC) revealed that the first PC presents the greatest accumulated variation (74%). Based on the first PC, the dose of 12m-3 ha-1 has greater influence for PH, SC, and CD. Due to the greater influence on the biometric characteristics of sunflower plants, the blood residue (12m-3 ha-1 = 98.4kg P ha-1), can be used as an alternative source of phosphorus for the cultivation of sunflower in clayey oxisols.