Fertirrigação na produção de mudas de Eucalyptus grandis nos períodos de inverno e verão

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bioenergy from stillage anaerobic digestion to enhance the energy balance ratio of ethanol production

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

Disponibilidade de n e k no solo e sua absorção pela videira de vinho fertirrigada no semiárido

Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

Effects of mineral stress on the vegetative development of greenhouse-grown bell pepper plants

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Acúmulo de micronutrientes em beterraba submetida a diferentes manejos de fertirrigação e niveis de salinidade

Knowledge of the amount of nutrients accumulated in the plant provides important information that can assist in the fertilization of crops program. To study the salt effect caused by high amounts of fertilizers applied by fertigation, an experiment was conducted in a greenhouse at the FCA/UNESP, Botucatu, SP. The experiment lasted 90 days (01/11/11 to 29/01/12) constituting five levels of electrical conductivity (1.0, 3.0, 6.0, 9.0, and 12.0 dS m-1), fertigation two management (M1: traditional management, M2: management by controlling the ionic concentration of the soil solution) and two varieties of beets (Early Wonder and Itapuã) blocks with 4 repeats forming a 5x2x2 factorial. From the dry weight of shoots and roots was determined the levels of micronutrients (B, Cu, Fe, Mn, Zn mg kg-1), and by multiplying the dry matter accumulation was determined in these plant . The accumulation of micronutrients in different parts of the plant followed the order: Fe> Mn> Zn> B> Cu for the different management fertigation studied. The Cu, Fe, Mn element present responses to increased soil salinity leading to greater absorption.

Absorção de micronutrientes em plantas de pimentão submetidas a diferentes lâminas de irrigação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Teores de macronutrientes em plantas de pimentão enxertadas sob fertirrigação

This study aimed at determining the levels of macronutrients (N, P, K, Ca, Mg and S) in grafted plants by contact methods such as bevel, cleft grafting by full rift and approach, as compared to non grafted plants. Analyses were performed in different parts of the plants under fertigation in a greenhouse. The hybrid and rootstock were AF 7125 and AF 8253, respectively. The nutrients were supplied via fertigation during the 150-day cycle. The experiment was carried out at the Teaching, Research and Production Farm in São Manuel city, SP which belongs to FCA-UNESP Campus in Botucatu city/SP. A total of 4 treatments and 5 replications were used. Each plot consisted of 12 plants. Chemical analyses were performed in one plant per plot at 35, 85, 112 and 143 days after transplantation to determine nutrient concentrations. The results showed that the macronutrient concentrations in a decreasing sequence in the vegetative parts (leaf + stem) were as follows: K > N > Ca > Mg > S > P; and in the fruits: K > N > P > S > Mg > Ca. Macronutrient concentrations were similar among grafted plants as compared to ungrafted plants, and the rootstock may have influenced absorption and translocation of minerals in grafted plants.

Lâminas de fertirrigação e substratos na produção e qualidade de gérbera de vaso

Fertigation management of gerbera crop has been many times performed inadequately, and it has been worsened when mixtures of substrates with different physical and chemical characteristics are used. Aiming at evaluating the production and quality of potted gerbera in two substrates and different levels of fertigation, the experiment was conducted in the greenhouse of the DRN/Soil Science, FCA/UNESP, Botucatu (SP). A 5 x 2 factorial randomized block design (5 levels of fertigation and 2 substrates) was adopted with 4 replications. Levels of fertigation corresponded to maintenance of 100% available water (AW) in the substrate; 100 to 80% of AW; 100 to 60% of AW; 100 to 40% of AW and 100 to 20% of AW. The substrates were as follows: 1- mixed coconut fiber (50% pellet coconut fiber and 50% coir fiber), 2- 40% red soil, 40% decomposed pine bark, 10% composition 1 (40% decomposed pine bark, 30% vermiculite and 30% carbonized rice husk) and 10% composition 2 (75% decomposed pine bark and 25% needles of pine). Plants at the marketing stage were evaluated according to the number of leaves; diameter of leaf surface; leaf area; fresh and dry phytomass of leaves, inflorescence and total plant; inflorescence number and diameter, stem diameter, plant height, leaf area rate and electrical conductivity of the substrate solution. Plants of better quality were obtained when they were maintained in levels of 100% available water and the mixed coconut fiber was used as substrate.

Relação K:Ca:Mg na solução nutritiva para produção de minitomate cultivado em substrato

The study was conducted to evaluate six K:Ca:Mg ratios for production of two cultivars of mini tomato grown in substrate, in a greenhouse, during two growing seasons. The experimental design was randomized blocks with four replications and twelve treatments using both cultivars of mini tomato (Sweet Million and Sweet Grape) and six K:Ca:Mg ratios (4:3:1, 6:3:1, 6:4.5:1, 2.7:3:1, 2.7:2:1, 4:2:1) in nutrient solutions. In both experiments, nutrient solutions with the highest concentrations of Mg, (75 mg L-1) and the lowest concentrations of Ca, (150 mg L-1) led to the highest concentrations of those nutrients in plant dry matter. The Sweet Million cultivar had higher yield (1.69 kg plant-1 and 1.52 kg plant-1), number of fruits per plant (227 and 236), and water use efficiency (29.1 kg m-3 and 25.3 kg m-3). However, the Sweet Grape cultivar had fruits of higher mean weight (9.0 g and 8.8 g) and macronutrient content in the leaves. In both crop cycles, the different K:Ca:Mg ratios affected only the macronutrient contents of the mini tomato plants grown in substrate, with no effect on yield and water use efficiency. The first crop cycle showed the highest N, K, Ca and S content.

Disponibilidade hídrica e utilização do nitrogênio em cana-de-açúcar irrigada por gotejamento subsuperficial

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Manejo de minimelancia cultivada em fibra da casca de coco, sob ambiente protegido

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

Manejo de minimelancia cultivada em fibra da casca de coco, sob ambiente protegido

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

Nitrogen fertilizer (15N) leaching in a central pivot fertigated coffee crop

Nitrogen has a complex dynamics in the soil-plant-atmosphere system. N fertilizers are subject to chemical and microbial transformations in soils that can result in significant losses. Considering the cost of fertilizers, the adoption of good management practices like fertigation could improve the N use efficiency by crops. Water balances (WB) were applied to evaluate fertilizer N leaching using 15N labeled urea in west Bahia, Brazil. Three scenarios (2008/2009) were established: i) rainfall + irrigation the full year, ii) rainfall only; and iii) rainfall + irrigation only in the dry season. The water excess was considered equal to the deep drainage for the very flat area (runoff = 0) with a water table located several meters below soil surface (capillary rise = 0). The control volume for water balance calculations was the 0 - 1 m soil layer, considering that it involves the active root system. The water drained below 1 m was used to estimate fertilizer N leaching losses. WB calculations used the mathematic model of Penman-Monteith for evapotranspiration, considering the crop coefficient equal to unity. The high N application rate associated to the high rainfall plus irrigation was found to be the main cause for leaching, which values were 14.7 and 104.5 kg ha-1 for the rates 400 and 800 kg ha-1 of N, corresponding to 3.7 and 13.1 % of the applied fertilizer, respectively.

Ajo nieve INTA : densidad de plantación y fertirrigación nitrogenada

Se estudió el efecto de tres densidades de plantación (20 (D20), 30 (D30) y 40 (D40) plantas m-2) y cinco dosis de fertilización nitrogenada (0 (N0), 75 (N75), 150 (N150), 225 (N225) y 300 (N300) kg de N ha-1), sobre el rendimiento y la calidad de ajo (Allium sativum L.) de la cultivar Nieve INTA (tipo blanco), bajo riego por goteo. Se realizó un ensayo en el INTA La Consulta, Mendoza, Argentina, en un suelo Torrifluvente típico franco arenoso profundo (Soil Taxonomy). Se utilizaron cintas de riego por goteo T-Tape 508-30, colocadas en el medio de la cama de plantación con un caudal de 2.7 L m-1 h-1. El máximo rendimiento (13 t ha-1) de ajo seco y limpio se logró con una densidad de plantación de 40 plantas m-2 y con dosis de 225 kg N ha-1. Las relaciones halladas entre los rendimientos de bulbos y las dosis de nitrógeno de 0, 75, 150, 225 y 300 kg N ha-1 fueron de tipo cuadrático (P < 0.001), con r2= 0.89; 0.91 y 0.84 para D 20, D30 y D40, respectivamente. Se encontró diferencias significativas (P < 0.05), con respecto a rendimiento, entre líneas externas e internas de la cama de plantación en la densidad de 40 000 plantas ha-1. La línea externa rindió más que la interna. Los porcentajes en peso de bulbos comerciales (C5+C6+C7) sobre el total de bulbos cosechados para las densidades D20, D30 y D40 fueron de 80.1 %; 66.7 % y 56.1 %, respectivamente.

Sustrato y dosis de fertirriego en la aclimatización de vitroplantas de Agave americana var. oaxacencis

Con la finalidad de asegurar la adaptación en invernadero de plantas de Agave americana var. oaxacensis obtenidas in vitro, se evaluó el efecto de sustratos y dosis de fertirriego en la aclimatización y crecimiento de 180 plantas. Este trabajo se realizó en un invernadero del Instituto Tecnológico del Valle de Oaxaca, México, a principios de 2012. Se utilizaron plantas recién salidas del laboratorio. El experimento se estableció según el diseño completamente al azar con arreglo factorial 2 (sustratos: arena y perlita) x 5 (fertilización: 1, 25, 50, 75 y 100%). La unidad experimental fue una planta en un recipiente de plástico de 150 cm3 con 18 repeticiones. La fertilización se basó en la solución universal de Steiner y diariamente cada planta recibió a nivel de sustrato 10 mL durante 12 semanas. Se evaluó el crecimiento en hojas, tallo y raíz, realizando análisis de varianza y prueba de medias (Tukey, α = 0,05). Todas las plantas se adaptaron, pero aquellas plantas establecidas en perlita lograron los mejores crecimientos en área foliar, volumen de raíz, peso fresco total, materia seca de raíz y total de planta. El tamaño de las plantas al término de su aclimatación estuvo en relación con la cantidad de nutrimentos de la solución nutritiva.