Acúmulo de macronutrientes por duas cultivares de cebola produzidas em sistema de semeadura direta

Economically, onion is the third more important vegetable in Brazil. As a consequence of the increasing by use of new hybrid varieties, the nutritional management of the crop needs to be adequately known. This research was carried out in São José do Rio Pardo, São Paulo State, Brazil, from March 7 to August 8, 2004. The objective was to quantify, under field conditions, the accumulation of macronutrients by onion cultivars established by direct sowing. The experimental design was in randomized blocks with three replicates. The cultivars studied were Optima and Superex. Samples were taken at 30, 50, 70, 90, 110, 130 and 150 days after sowing. With population of 354,000 plants ha -1 and productivity estimated in 64.8 t ha -1, 'Optima' extracted on 150 days after sowing: 78.77, 13.04, 75.77, 59.09, 11.70 and 24.38 kg ha -1 of N, P, K, Ca, Mg and S, respectively, and 'Superex', for the same plant population, and productivity at 72 t ha -1, 64.68, 10.33, 68.28, 65.58, 13.03 and 24.74 kg ha -1 of N, P, K, Ca, Mg and S, respectively. The Optima hybrid exported through its bulb about 49.17% of N, 60.60% of P, 61.16% of K, 41.15% of Ca, 43.56% of Mg, and 47.18 of S, the equivalent to 38.73, 7.90, 46.34, 24.32, 5.10 and 11.51 kg ha -1, respectively. The Superex hybrid exported through its bulb about 44.29% of N, 55.85% of P, 62.54% of K, 35.71% of Ca, 31.82% of Mg, and 48.80% of S, the equivalent to 28.65, 5.77, 42.70, 23.42, 4.15, and 12.07 kg ha -1, respectively.

Condutividade elétrica da solução nutritiva e acúmulo de macro e micronutrientes no cultivo de crisântemo

The study of growth and uptake of nutrients is important to determine the times of increased demand in order to schedule the fertigation. The present research was developed with the objective of evaluating the effects of different levels of electrical conductivity on growth and accumulation of nutrients in chrysanthemum plants under greenhouse conditions. The electrical conductivity levels on the applied solution were 1.42, 1.65, 1.89, 2.13 and 2.36 dS m-1 (bud vegetative stage); 1.71, 1.97, 2.28, 2.57 and 2.85 dS m-1 (bud stage). The dry mass of the aerial portion of the plant and the contents of macronutrients and micronutrients were determined every 14 days. The nutrient accumulation in chrysanthemum plant showed similar trend as compared to dry matter accumulation. The nutrients presented the following order of absorption: K>N>Ca>Mg>P>S (1425, 892, 184, 150, 110 and 59 mg plant-1) and Fe>Zn>B>Mn>Cu (2254, 2219, 1725, 1287, 210 μg plant-1). The content of most nutrients increased with increase in electrical conductivity of the solution, without salt effect up to EC of 2.85 dS m-1.

Upland rice growth and mineral nutrition as affected by cultivars and sulfur availability

A better understanding of the differential growth of upland rice (Oryza sativa L.) cultivars with increasing soil S availability could help improve rice yield under upland conditions. The objective of this study was to evaluate root and shoot growth and nutrition of upland traditional and modern rice cultivars as affected by S availability. The experimental design was completely randomized in a 3 (rates of S) × 3 (cultivars) factorial with four replications. Low availability of S in the soil reduces root and shoot development and the efficiency of N, P, and S uptake, as well as the concentration and content of these nutrients in rice cultivars. At 0 mg dm-3 of S, rice cultivars prioritize root growth over shoots, and the traditional cultivar does so with greater intensity. Our results suggested that more development of traditional cultivars under low S availability facilitates its adaptation in soils under this condition. On the other hand, the intermediate and modern cultivars are more responsive to S fertilization. Moreover, S fertilization allows significant increases in upland rice growth and must be considered in cropping systems aiming for high yields. © Soil Science Society of America.

Exportação de nutrientes em plantas de jambu, sob diferentes adubações

The jambu is a broad vegetable consumption in Northern Brazil, especially in Pará, known by the jambu and other common names is native to the Amazon region has been used and cultivated for culinary and also recently in natural medicines by their chemical properties, attributed to the spilanthol compound. Knowing the amount of nutrient uptake in plants, especially at the taken, it is important to evaluate the removal of nutrients necessary for economic fertilizer recommendations. So the goal of this project was to determine the accumulation of nutrients in plants of jambu (leaf and inflorescence) under different fertilizations. The experiment was conducted at São Manuel Experimental Farm UNESP. The statistical was arranged in the randomized block design, in a 2 x 6 factorial scheme, two sources of fertilizers (organic and mineral) and six doses of nitrogen, with four replications. We evaluated the macronutrients of accumulation N, P, K, Ca, Mg, S and micronutrients of accumulation B, Cu, Fe and Zn in leaves and inflorescence. The plants responded more jambu nutrients of translocation phosphorus (P), magnesium (Mg), sulfhur (S), boron (B), copper (Cu) and iron (Fe) in the inflorescences and phosphorus (P), calcium (Ca), manganese (Mg), sulfur (S), boron (B), copper (Cu) and iron (Fe) in leaves to organic fertilization demonstrating the effectiveness of using this source of fertilizer nutrients indicating that this was a defining characteristic in response to the accumulation of nutrients in the leaves and inflorescences jambu. Plants jambu are more responsive to fertilizer for the mineral of translocation nitrogen (N) and manganese (Mn) for both the sheet and for the inflorescences of plants jambu.

Absorção de nitrogênio pelo algodoeiro herbáceo em dois sistemas de cultivo

The study of nutrient uptake is of fundamental importance to plant nutrition, as well as tell the time (growth stage) being absorbed by the culture, also signals to the levels of fertilizer to be used. Aiming to establish the uptake of nitrogen for cultivation of cotton (Gossypium hirsutum L. r. latifolium Hutch.) led to an experiment in a Alfissol under randomized block design with two treatments, sowing conventional tillage and after tillage on the straw of previous crop (millet), with five replicates. Samples were taken according to the phenology and plants development. The dry matter accumulation in cotton is linear and increasing until the period of large boll, being more intense with the appearance of flowers and boll, or 50 to 100 days after emergence. The nitrogen content is higher in newly emerged plants, having peaks at the beginning of the appearance of squares and flowers, and from the appearance of small boll, the nitrogen content in the plant decreases linearly. The extraction of nitrogen is bigger from the appearance of flowers (55-60 days after emergence).

Acúmulo e exportação de nutrientes em cenoura 'Forto'

In order to quantify the growth, accumulation and exportation of macronutrients by carrot 'Forto', and obtain equations that best represent them, it was conducted an experiment in the São Gotardo (MG), from May to September 2004. Samples were taken at 40, 50, 60, 70, 80, 90, 100, 110 and 120 days after sowing (DAS) to determine dry matter and accumulation of macronutrients in leaves and roots. At 40 DAS, five days after thinning, the plants had 0.18 g and 0.04 g in dry leaves (LDM) and of roots (RDM), respectively. From then, until 88 DAS, the partitioning of photoassimilates and accumulation of matter in the shoots were more pronounced. The RDM was low until 80 DAS, which corresponded to two thirds of the crop cycle, from when the amount of material allocated in this part of the plant had strong growth, surpassing, at 88 DAS, the amount of LDM. The nutrient accumulation was small in the first 60 DAS, coinciding with the period of lower dry matter accumulation. The order of decreasing macronutrient accumulation by the crop were: K > N > Ca > P > S > Mg, in the amounts of 906.7, 438, 155.46, 87.4, 58 and 37.63 mg plant-1, respectively. The root participated with 60.5% of the accumulation of N, 86.1% of P, 58% of K, 25.5% of Ca, 55.6% of Mg and 65.5% of S. Considering a population of 590,000 plants per hectare, the total quantity of nutrients by the crop of carrots was 258.3, 51.6, 534.8, 91.7, 22.2 and 34.2 kg N ha-1, P, K, Ca, Mg and S, respectively.

Eficiência de escórias de siderurgia na cultura do feijoeiro em sistema de semeadura direta

In the no till system, soil acidity correction practice is restricted to limestone use and there is little information regarding slag. The study aimed to evaluate the amendments in soil chemical properties, yield and bean nutrient uptake according to the application forms of slags, compared to limestone, in the implantation of no till system. The experiment was conducted in the field at College of Agricultural Sciences, Botucatu (SP) from December 2010 to May2011. The treatments consisted of two application ways of seven soil acidity correctives: steel slag, blast furnace slag, ladle furnace slag, stainless steel slag (agrosilício), wollastonite, lime and calcined dolomite lime, plus one control without corrective application. Each material dose was calculated to raise the base saturation to 70%. Soil acidity was neutralized down to 20cm with limestones, whereas for wollastonite and ladle furnace slag those effects occurred down to 10cm, for steel slag, blast furnace slag and agrosilício the corrective effect was restricted to the first 5cm. The bean yield increased by application of correctives in soil acidity, without differences between the application ways.

Crescimento, produtividade, acúmulo e exportação de nutrientes em cultivares de batata (Solanum tuberosum L.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Marcha de absorção de macronutrientes e de micronutrientes em mudas de goiabeira Paluma e Século XXI

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Crescimento e acúmulo de macronutrientes em cenoura Forto‟

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Acúmulo de nutrientes e desempenho agronômico do pimenteiro (Capsicum Annum L.) em função dos métodos de enxertia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Doses de composto orgânico, com e sem fósforo adicionado ao solo, na produção e qualidade de sementes de alface

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Absorção de nutrientes em duas cultivares de copo-de-leite colorido (Zantedeschia sp.) sob fertirrigação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resposta de Panicum maximum Jacq. cv. Tanzânia à aplicação de soro ácido de leite

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Crescimento, acúmulo de macronutrientes e produção de chicória em função do período de proteção com polipropileno

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)