RESUMEN La acumulación de nutrientes durante la formación de árboles de carambola (Averrhoa carambola) puede ser afectado por el régimen de agua y por el cultivar, sin embargo, esto aún no es conocida para esta especie. El propósito de este estudio fue evaluar la acumulación de nutrientes de dos cultivares de carambola en fase de formación, bajo dos regímenes de irrigación. El experimento fue realizado en campo, mediante diseño completamente al azar, con parcelas divididas, siendo estas parcelas dos niveles de irrigación (con y sin irrigación) y, como subparcelas, dos cultivares de carambola (B-10 y Golden Star) y siete épocas de recogida de plantas, entre 0 a 720 días después del transplante (DAT), con seis réplicas. La acumulación de nutrientes fue evaluada en el tallo y las hojas, y fue posible observar que la toma de nutrientes y la tasa promedio de acumulación siguió la acumulación de masa seca de los árboles de carambola en formación. La acumulación de nutrientes por la parte aérea a los 720 DAT fue diferente, siendo que para la 'Golden Star' en el régimen seco y para la 'B-10' en ambos regímenes de irrigación no hubo diferencia, siguiendo la secuencia Ca > K > N > Mg > S > P > Mn > Fe > Zn > B > Cu, y para el cultivar Golden Star en el régimen irrigado, la secuencia de acumulación fue Ca > K > N > Mg > Mn > P > S > Fe > Zn > B > Cu. La más alta acumulación ocurrió en el régimen irrigado, independientemente del cultivar. El cultivar Golden Star acumuló, en promedio, cantidades mayores de N, P, K, Mg, S, Fe y Mn.

ABSTRACT Nutrient accumulation during the formation of star fruit (Averrhoa carambola) trees can be affected by the water regime and by the cultivar, but the details are not yet known for this species. The aim of this study was to evaluate the nutrient uptake of two star fruit cultivars in the formation phase under two irrigation regimes. The experiment was developed with a completely randomized design, with subdivided plots, with two irrigation levels (with and without irrigation) as plots, and two star fruit cultivars as subplots ('B-10' and 'Golden Star') and seven collection times from 0 to 720 days after transplanting (DAT) into the field as sub-subplots with six replicates. Nutrient uptake was evaluated in stem and leaves, and it was possible to observe that nutrient uptake and the average accumulation rate followed the dry matter mass accumulation of star fruit trees in formation. Nutrient uptake by shoots at 720 DAT differed for the Golden Star cultivar in the rainfed regime and for the B-10 cultivar in both irrigation regimes. There was no difference and followed the sequence Ca > K > N > Mg > S > P > Mn > Fe > Zn > B > Cu, and for Golden Star cultivar in the irrigated regime, the accumulation sequence was Ca> K> N> Mg> Mn> P> S> Fe> Zn > B> Cu. The highest accumulation occurred in the irrigated regime regardless of cultivar. Golden Star cultivar accumulated, on average, larger amounts of N, P, K, Mg, S, Fe and Mn.

Resumen Existe fuentes alternativas de micronutrientes han aparecido en el mercado de los complejos de B, Mn y Zn con polioles, respecto a fuentes convencionales, lo cual es una preocupación cuando se busca una alta eficiencia de la fertilización. El objetivo de este estudio fue evaluar los niveles de Mn, B y Zn en hojas y granos, conjuntamente con el rendimiento de granos en función de la aplicación foliar de dosis y fuentes de Mn y B en soja y Zn en maíz. Se estudiaron diferentes fuentes de Mn (sulfato de manganeso, quelato de Mn-EDTA y complejo de Mn con lignosulfonato y con poliol), B (ácido bórico, complejo B con poliol) en soja y Zn (sulfato de zinc, Zn-EDTA y complejo de Zn con poliol) La aplicación foliar de fuentes y dosis de Mn y B en los cultivos de soja y Zn en el cultivo de maíz no influye en la nutrición de las plantas y la producción de granos. La aplicación foliar de fuentes solubles, quelatos y fuentes alternativas de Mn, B en los cultivos de soja y Zn en cultivos de maíz presentan eficiencias agronómicas similares en la nutrición de las plantas y la producción de granos.

Abstract Alternative sources of micronutrients have appeared on the market from B, Mn, and Zn complexes with polyols without scientific evidence on their agronomic effects compared to conventional sources, which is a concern when high fertilizer efficiency is sought Leaf. This study's objective was to evaluate the levels of Mn, B, and Zn leaf and grain and grain yield as a function of foliar ap plication of doses and sources of Mn and B in soybean and Zn maize. They studied different sources of Mn (manganese sulphate, Mn-EDTA chelate, and Mn complex with lignosulfonate and with polyol), B (boric acid, B complex with polyol) in soybean and Zn (zinc sulfate, Zn-EDTA and Zn complex with polyol). Foliar application of sources and doses of Mn and B in the soybean and Zn crops in the maize crop does not influence plant nutrition and grain production. Foliar application of soluble sources, chelates, and alternative sources of Mn, B in the soybean, and Zn crops in maize crops present similar agronomic efficiencies in plant nutrition and grain production.

Resumo É conhecido o efeito benéfico do silício nas plantas, porém não há trabalhos que demonstre qual o efeito deste elemento na produção de proteína e lignina em plantas ornamentais. Este trabalho teve como objetivo avaliar os efeitos da aplicação via fertirrigação de ácido monossilícico nas doses de 0, 2, 4 e 8 mmol L-1 de Si, na produção de proteína e lignina, em duas espécies ornamentais: Viola x wittrockiana Gams ex Nauenb. & Buttler ‘Majestic Giants II Fire’ e Tagetes erecta L. ‘Hero’ (mistura de cores). O experimento foi instalado em esquema fatorial 4 x 2 em delineamento inteiramente casualizado, com cinco repetições. Após 90 dias da semeadura, foram avaliados o teor de N da parte aérea, acúmulo de Si na parte aérea, raiz e total e produção de lignina e proteína. Houve aumento na lignina seguido de redução, a partir da concentração de 2,0 (4,29) e 4,3 (5,72) mmol L-1 de Si em Viola e Tagetes, respectivamente. Também, promoveu aumento do teor de lignina em T. erecta e V. x wittrockiana.

Abstract The beneficial effect of silicon on plants is known, but there are no studies demonstrating the effect of this element on protein and lignin production in ornamental plants. This study aimed to assess the effects of monosilicic acid fertigation at 0, 2, 4, and 8 mmol L-1 of Si on protein and lignin production of two ornamental species: Viola x wittrockiana Gams ex Nauenb. & Buttler ‘Majestic Giants II Fire’ e Tagetes erecta L. ‘Hero’ (color mix). The experiment was installed in a 4 × 2 factorial arrangement using a completely randomized design with five replications. After 90 days of the sowing, we assessed N and Si contents in shoot system, Si accumulation in shoot system, root, and total, and lignin and protein production. An increase in lignin followed by its reduction was observed from the concentration of 2.0 (4.29) and 4.3 (5.72) mmol L-1 of Si for Viola and Tagetes species, respectively. Silicon application promoted higher lignin content in T. erecta and V. x wittrockiana.

ABSTRACT Several complications can arise, either directly or indirectly, from implementation of measures to correct soil acidity in established fruit orchards, such as impaired roots, lower root volume, risk of plant infection, propagation of diseases, promotion of pest development (especially nematodes), and soil disaggregation and compaction. These factors can have a negative effect on crop yield. Therefore, it becomes critical to implement an effective method of neutralizing soil acidity, especially at the level of the tree roots. To assess the effect that the rates and forms of limestone applied on the soil surface have on soil fertility and on nutrition and yield of guava, an experiment was conducted in a commercial orchard. A randomized block experimental design was implemented with three replicates consisting of two forms of limestone [common limestone with relative neutralizing value (RNV) = 80 % and calcined limestone with RNV = 131 %], which were applied at five different rates (0, 0.5, 1, 1.5, and 2 times the recommended rate to raise the V value to 70 %), without incorporation. Liming with common or calcined limestone caused a drop in soil acidity in the 0.00-0.10 m layer at 6, 12, and 24 months after application. Soil acidity decreased in the 0.10-0.20 m layer at 6 and 12 months after use of calcined limestone, and at 24 months after liming with the common form of limestone. The chemical composition (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn) of leaves was not affected at 14 months after surface liming treatments, nor the chemical composition of fruit at 20 months after the treatments. Guava yield was not affected by surface liming.

Abstract The method used to dry plant tissue samples may modify its nutrient content, and results in incorrect diagnostic of crop nutritional status. The hypothesis was that microwave drying method does not affect the nutrient content of leaves neither the interpretation of the results, as compared to oven-drying procedure. In this study we evaluated the effect of microwave drying of eucalyptus (Corymbia Citriodora (Hook.)) and rubber trees (Hevea brasiliensis Muell. Arg.) leaves on dry matter and macronutrient content, as compared to oven drying. The study was performed in a laboratory at the Department of Soils and Fertilizers of Universidade Estadual Paulista “Julio de Mesquita Filho”, UNESP, Jaboticabal-SP-Brazil. The experiments were: one using leaf samples of eucalyptus and other using leaf samples of rubber trees. The experimental design was completely randomized and treatments were drying in conventional oven and in microwave oven, with 10 repetitions. Data were analyzed using ANOVA and treatments means were compared with F test and Tukey test (p≤0.05). The dry matter and the macronutrient content of each sample were determined. There were no differences between the drying methods on leaf nutrient content, except for N content of rubber trees. Similar dry matter content was obtained for rubber trees and eucalyptus samples. Microwave drying is useful as an alternative method to dry plant tissues samples aiming to its chemical analysis.

Resumen El método usado para secar muestras de tejido vegetal puede modificar su contenido de nutrientes, lo cual resulta en un diagnóstico incorrecto del estado nutricional del cultivo. La hipótesis fue que un método de secado con microondas no afecta el contenido de nutrientes en las hojas, ni la interpretación de los resultados, comparado con secado con calor. En este estudio evaluamos el efecto del secado en microondas sobre la materia seca y el contenido de macronutrientes de hojas de eucalipto (Corymbia Citriodora (Hook.)) y caucho (Hevea brasiliensis Muell. Arg.), comparado con el secado en horno. El estudio se realizó en el laboratorio del Departamento de Suelos y Fertilizantes de la Universidad Estadual Paulista “Julio de Mesquita Filho”, UNESP, Jaboticabal-SP-Brasil. Los experimentos se establecieron: uno con muestras de hojas de eucalipto y otro con hojas de árboles de caucho. El diseño experimental fue completamente al azar, los tratamientos fueron dos secado en horno convencional, y en horno microondas, con 10 repeticiones. Los datos se analizaron con ANDEVA y las medias de tratamiento se compararon con la prueba de F y la de Tukey (p≤0.05). La materia seca y el contenido de macronutrientes de cada muestra fueron evaluados. No hubo diferencias entre los métodos de secado sobre el contenido de nutrientes foliares, excepto el contenido de N en las muestras de árboles de caucho. La materia seca en las muestras de caucho y eucalipto fue similar. El secado por microondas es útil como un método alternativo para muestras de tejidos vegetales y con el objetivo de análisis químicos.

Abstract Doubts remain about the adequate iron (Fe) concentration in nutrient solutions used for optimal plant growth, especially in gramineae like sugar cane (Saccharum officinarum L.). Therefore, the aim of this study was to evaluate the effect of Fe concentrations on growth, green color index and dry matter (DM) production in sugar cane cultivated in a nutrient solution. The hypothesis was that the nutrient solution must contain higher Fe concentration, which is used by the plant for optimum development. The study was conducted in a greenhouse with the variety IAC SP 93 3046, cultivated in pots (7.5 L) with aerated nutrient solution. The experimental design was completely randomized with five replicates and four treatments (0; 184; 368 and 551.4 μmol L-1 of Fe-EDDHA). For data analysis we used ANOVA with an F test (p≤0.05). Variables evaluated were plant height, stem diameter, leaf area, green color index, DM production, total Fe accumulation and we also performed visual diagnosis. Both leaves and roots had greater Fe accumulation of 0.28 g and 2 g per pot, respectively, on the Fe-EDDHA concentration of 184 μmol L-1. Green color index and nutrient accumulation were greater with increased FeEDDHA concentrations. The concentration of 184 μmol L-1 met the needs of the plant, providing a 12.2 mm diameter, 25 cm height, 750 cm2 leaf area and 4.10 g of DM per pot, 2.18 g of roots per pot and 6.28 g of whole plant per pot. The use of Fe-EDDHA chelate increased both the element’s buildup in plants and green color index; and 184 μmol L-1 Fe was the adequate concentration to supply the plant’s needs, promoting satisfying DM production.

Resumen Hay dudas acerca de la concentración adecuada de hierro (Fe) en soluciones nutritivas para el crecimiento óptimo de las plantas, sobre todo en gramíneas como la caña de azúcar (Saccharum officinarum L.). Por lo tanto, el objetivo de este estudio fue evaluar los efectos de las concentraciones de Fe sobre el crecimiento, índice de color verde y la producción de materia seca (MS) en la caña de azúcar cultivada en una solución nutritiva. La hipótesis fue que la solución nutritiva debe tener una concentración más alta de Fe, el cual es usado por la planta para su desarrollo óptimo. El estudio se realizó en un invernadero con la variedad IAC SP 93 3046, cultivada en maceras (7.5 L) con una solución nutritiva aireada. El diseño experimental fue completamente al azar con cinco réplicas y cuatro tratamientos (0; 184; 368 y 551.4 μmol L-1 de Fe-EDDHA). Para el análisis de los datos se usó ANDEVA con una prueba F (p≤0.05). Las variables evaluadas fueron la altura de la planta, diámetro del tallo, área foliar, índice de color verde, producción de MS, acumulación total de Fe y también se realizó un diagnóstico visual. Tanto hojas como raíces presentaron mayor acumulación de Fe de 0.28 g y 2 g por maceta, respectivamente, en la concentración de Fe-EDDHA de 184 μmol L-1. El índice de color verde y la acumulación de nutrientes fueron mayores a mayores concentraciones de Fe-EDDHA. La concentración de 184 μmol L-1 cubrió las necesidades de la planta, al dar un diámetro de 12.2 mm, altura de 25 cm, 750 cm2 de área foliar y 4.10 g de MS por maceta, 2.18 g de raíces por maceta y 6.28 g de planta entera por maceta. El uso del quelato Fe-EDDHA aumentó la acumulación del elemento en las plantas y el índice de color verde; y 184 μmol L-1 Fe fue la concentración adecuada para satisfacer las necesidades de la planta, promoviendo la producción satisfactoria de MS.

RESUMO O surgimento de novos híbridos de milho pode afetar a tolerância à deficiência nutricional. Objetivou-se, com este trabalho, caracterizar os sintomas visuais de deficiência de macronutrientes e sua relação com o crescimento, os teores e o acúmulo de nutrientes em milho. O experimento foi realizado em delineamento inteiramente casualizado, com sete tratamentos e três repetições. Os tratamentos consistiram na solução completa de Hoagland & Arnon (1950), com omissões de N, P, K, Ca, Mg e S. O início dos sintomas de deficiência de N, P, K, Ca e Mg ocorreram aos 5, 16, 16, 16 e 22 dias após o transplantio, respectivamente. O milho apresentou menor produção de matéria seca com a omissão de N, P, K, Ca e Mg, em comparação com o tratamento completo. Os sintomas de deficiência de N, P, K, Ca e Mg foram observados na parte aérea do milho com teores iguais a 7,8; 1,2; 15,7; 1,8 e 0,7 g kg-1, respectivamente. No tratamento completo, os teores de N, P, K, Ca e Mg na parte aérea foram de 30,6; 5,9; 63,7; 6,0 e 4,5 g kg-1, sem sintomas de deficiência. A produção de matéria seca diminui quando há a omissão dos nutrientes, tanto para parte aérea como para raízes, e os tratamentos que apresentaram menor produção de matéria seca foram a omissão de N e a de K. A omissão de um nutriente, além de diminuir seu teor na parte aérea, causa desequilíbrio entre os demais nutrientes e, consequentemente, provoca sintomas característicos de deficiência de cada nutriente.

ABSTRACT The emergence of new corn hybrids may affect tolerance to nutritional deficiency culture. This study aimed to characterize the visual symptoms of macronutrient deficiency and its relation to the development, content and nutrient accumulation in maize. The experiment was arranged in entirely randomized design, with seven treatments and three replications. The plants were cultivated in nutritive complete solution of Hoagland & Arnon (1950), and the omission of N, P, K, Ca, Mg and S. The onset of symptoms of deficiency of N, P, K, Ca and Mg occurred at 5, 16, 16, 16 and 22, days after the transplant, respectively. The corn had lower dry matter production in the omission of N, P, K, Ca and Mg in relation to the complete treatment. Symptoms of deficiency of N, P, K, Ca and Mg were observed in the shoots of corn with levels equal to 7.8; 1.2; 15.7; 1.8 to 0.7 g kg-1 , respectively. Complete treatment in the N, P, K, Ca and Mg in the shoots were 30.6; 5.9; 63.7; 6.0 and 4.5 g kg-1, in that order, good nutritional status. The dry matter production will decrease in the omission of nutrients in the aerial part and in the roots, and the treatments had lower dry matter production were the omission of N and K. The absence of a nutrient, and reduce its content in the shoot, cause imbalance between the other nutrients, thus providing characteristic symptoms of deficiency of each nutrient.

The present work aims to evaluate the effect of three phosphorus sources, filter cake and microorganisms on the morphometric variables in tomato seedlings (Solanum lycopersicum L.). The investigation was carried out under greenhouse conditions in the Citrico Arimao Enterprise. A Brown soil without carbonate differentiation was used, to which was carried out an agrochemical analysis previously. An experimental design totally randomized was used, with factorial arrangement 3 x 3 + 1, and three repetitions. As a source of phosphorous triple superphosphate, simple superphosphate and a natural phosphoric rock were used and the three levels of organic fertilization consisted of the application of filter cake, filter cake enriched with Azotofos biofertilizer and without filter cake. At 45 and 60 days, the morphometric variables, height, diameter of the stall, the mass of the aerial part and of the root were measured. Variance analyses for all the variables were carried out. The media were compared by Tukey test with a level of error probability of 5 %. The ASISTAT statistical package was used. The morphometric variables, height, diameter of the stall, fresh mass of the aerial part and roots of the tomato seedlings at 45 and 60 days increased with the addition of filter cake, enriched or not, and the application of the phosphoric rock.

El objetivo del presente trabajo fue evaluar el efecto de tres fuentes de fósforo, cachaza y microorganismos sobre las variables morfométricas en plántulas de tomate. La investigación se realizó en la Empresa Cítricos Arimao. El suelo empleado fue Pardo sin diferenciación de carbonato, al cual se le realizó previamente un análisis agroquímico. Se empleó un diseño experimental completamente aleatorizado con arreglo factorial 3 x 3 + 1 (tres fuentes de fósforo, tres niveles de fertilización orgánica y un tratamiento control absoluto) y tres repeticiones. Se utilizaron como fuentes de fósforo el superfosfato triple, el superfosfato simple y una roca fosfórica natural. Los niveles de fertilización orgánica consistieron en la aplicación de cachaza, cachaza enriquecida con el biofertilizante Azotofos y sin cachaza. Se determinaron, a los 45 y 60 días, las variables morfométricas altura, diámetro del tallo, así como la biomasa de la parte aérea y de la raíz. Se analizaron estadísticamente cada una de las variables. Las medias se compararon por la prueba de Tukey para un nivel de probabilidad de error de 5 %. Se empleó el paquete estadístico ASISTAT. Las variables morfométricas altura, diámetro del tallo, biomasa fresca en la parte área y en la raíz de las plántulas de tomate se incrementan a los 45 y 60 días con la adición de cachaza, cachaza enriquecida y la aplicación de la roca fosfórica.

Maximum efficiency of nitrogen (N) is attained when fertilizer is accompanied by silicon (Si). Therefore, the objective of this study was to evaluate the chemical attributes of the soil, the nutritional status, the yield of stalks, and the accumulation of N and Si by a fourth ratoon sugarcane (Saccharum sp.) crop, and the influence of N doses in the presence and absence of Si and lime. The study was carried out at the experimental farm of the UNESP Jaboticabal campus, state of São Paulo, Brazil. The experimental design was in a completely randomized block with a 5x2 factorial scheme: five doses of N (0, 40, 80, 120, and 160 kg ha-1), and two corrective materials, silicate and lime; with four replications per treatment. The soil was characterized as distrophic Red Latosol, and the sugarcane variety was RB855156. During the experiment, the N (N-NH4+ and N-NO3-) and Si content in the soil, the N and Si content in the leaf, production of stalks, and the accumulation of N and Si in the leaves and stalks were measured. Nitrogen fertilization associated with silicate and limestone increased the levels of N-NO3- and Si in the soil, and improved nutritional status and accumulation of N and Si in leaves and stalks of sugarcane; but, stalk production was lower when using silicate as compared to lime.

La eficiencia máxima de nitrógeno (N) se alcanza cuando el fertilizante de N se usa con silicio (Si). Por tanto, el objetivo de este estudio fue evaluar los atributos químicos del suelo, el estado nutricional, la producción de tallos y la acumulación de N y Si en el cuarto cultivo de soca de caña (Saccharum sp.), y la influencia de la dosis de N en presencia y ausencia de Si y cal. El estudio se realizó en la granja experimental del campus UNESP-Jaboticabal, estado de São Paulo, Brasil. El diseño experimental fue de bloques completos al azar con un arreglo factorial de 5x2: cinco dosis de N (0, 40, 80, 120 y 160 kg ha-1), y dos materiales correctivos, silicato y cal; con cuatro repeticiones por tratamiento. El suelo se clasificó como Latosol Rojo distrófico y la variedad de caña de azúcar fue RB855156. Durante el experimento se midieron el contenido de N (N-NH4+ y N-NO3-) y Si en el suelo, el contenido de N y Si en la hoja, la producción de tallos y la acumulación de N y Si en las hojas y tallos. La fertilización con N asociada con silicato y caliza aumentó los niveles de N-NO3- y Si en el suelo, lo cual mejoró el estado nutricional y la acumulación de N y Si en las hojas y tallos de la caña de azúcar, pero la producción de tallos fue menor al usar silicato, comparado con cal.

La descontaminación de las muestras de hojas de cultivos pulverizados con pesticidas y soluciones nutritivas es importante para el análisis foliar. Este estudio evaluó el efecto de diferentes métodos de lavado en hojas de café y de sorgo que habían sido pulverizadas con zinc, con y sin surfactante. Siete días más tarde, las hojas se recogieron y se lavaron. El diseño experimental fue completamente aleatorizado, en esquema factorial 2 x 2 x 3 + 2, con tres repeticiones. El primer factor representa aplicaciones foliares de zinc con o sin surfactante; el segundo representa el número de lavados (1 ó 2), y el tercero la concentración de la solución de lavado (detergente + ácido clorhídrico) en (0 + 0 mL L-1; 1,0 + 3,5 mL L-1 y 2,0 + 7,0 mL L-1). El último factor representa dos tratamientos adicionales sin lavar (zinc rociado con y sin surfactante). El surfactante refuerza el contacto entre el zinc y el follaje y mejora la absorción. El lavado es un tratamiento previo indispensable para el análisis foliar, y nuestro estudio mostró que un solo lavado con detergente + ácido clorhídrico ( 1,0 + 3,5 mL L-1) fue el método de lavado más eficaz para el café y el sorgo

Decontaminating leaf samples from crops sprayed with pesticides and nutrient solutions is important for foliar analysis. This study evaluated the effect of different washing methods in coffee and sorghum foliage that had been sprayed with zinc (with or without surfactant). The plants were sprayed with a 3 g L-1 zinc sulfate solution, with and without surfactant. Seven days later, leaves were collected and washed. The experiment was completely randomized in a 2 x 2 x 3 + 2 factorial, with three replications. The first factor represents foliar zinc applications with or without surfactant, the second represents the number of washes (1 or 2) and the third represents the concentration of the wash solution (detergent + hydrochloric acid) at (0 + 0 mL L-1; 1.0 + 3.5 mL L-1 and 2.0 + 7.0 mL L-1). The last one represents two additional treatments without washing (zinc sprayed with and without surfactant). Surfactant strengthens contact between zinc and foliage and enhances absorption. Washing is an indispensable pretreatment for leaf analysis and our study showed that a single wash with detergent + hydrochloric acid (1.0 + 3.5 mL L-1) was the most effective washing method for coffee and sorghum

O uso de biofertilizantes associados a composto orgânico e rocha fosfatada pode aumentar a disponibilidade de fósforo no solo, pelo aumento da população de micro-organismos. Objetivou-se avaliar o efeito do uso da torta de filtro enriquecida com fosfato natural e preparados de biofertilizantes na população de micro-organismos e no teor de fósforo de um Latossolo Vermelho distrófico. O experimento foi realizado em casa-devegetação, utilizando-se delineamento experimental inteiramente casualizado, em esquema fatorial 7x3 (sete tratamentos e três épocas de avaliação), com três repetições. Os tratamentos consistiram de amostras de solo com adições de torta de filtro decomposta e rocha fosfatada de Araxá enriquecida com microorganismos provenientes dos biofertilizantes Biopack, Embrafos e Azotofos; solo com adições de torta de filtro e rocha fosfatada de Araxá, sem enriquecimento com micro-organismos; solo com torta de filtro; solo com rocha fosfatada; e somente solo (controle). Avaliou-se, aos 30, 60 e 90 dias após a instalação do experimento, o teor de fósforo disponível no solo e a população de micro-organismos. A presença de torta de filtro enriquecida com fosfato natural e com biofertilizantes promoveu aumento na população de bactérias do solo, havendo variações no tempo. A torta de filtro também proporcionou aumento na população de fungos e micro-organismos solubilizadores de fosfato. A curto prazo, a adição de torta de filtro enriquecida com fosfato natural contribuiu para o aumento do teor de fósforo solúvel no solo.

The use of biofertilizers associated with organic compound and phosphate rock can increase the availability of phosphorus in the soil, due to the increase of the microorganisms population. This study aimed at evaluating the effect of filter cake enriched with rock phosphate and biofertilizers preparations on the microorganisms population and phosphorus content of a Haplustox soil. The experiment was conducted in a greenhouse, in a completely randomized experimental design, in a 7x3 factorial scheme (seven treatments and three sampling times), with three replications. Treatments consisted of soil samples with decomposed filter cake and Araxá rock phosphate enriched with microorganisms from the biofertilizers Biopack, Embrafos and Azotofos; soil with filter cake and Araxá rock phosphate not enriched with microorganisms; soil with filter cake; soil with rock phosphate; and single soil (control). The soil phosphorus content and microorganisms population were evaluated at 30, 60 and 90 days after the experiment installation. The use of filter cake enriched with rock phosphate and biofertilizers increased the soil bacteria population, with variations in time. The filter cake also increased the fungi population and phosphate solubilizing microorganisms. In the short term, the addition of filter cake enriched with rock phosphate contributed to the increase of the soil soluble phosphorus content.

The way of applying zinc can influence the zinc uptake and productivity of crops, especially cereals that have high demand for this nutrient. The aim of this study is to evaluate methods of Zn application on soil, nutritional status and productivity of maize. For this, an experiment was undertaken at FCAV/UNESP, Jaboticabal-SP, in Oxisol clay (DTPA on Zn: 0.5 mg dm-3) with maize (hybrid Simple Impact), from December through May 2009. Nine treatments with three doses of Zn in soil banded application (in furrows) and three doses of Zn by incorporation in soil (0-20 cm depth), foliar application, seed application and control (no Zn). The treatments were arranged in a randomized block design with four replications. Regardless of the method, Zn application promoted higher contents of this micronutrient in soil and higher accumulation in the shoots as well as increasing Zn in the maize grain. However, it did not affect the nutritional status and yield of the maize. The Zn application in the soil resulted in a greater Zn uptake by plants and maize yield, compared to Zn application in the plant by seed or foliar.

La manera de aplicar zinc puede influir en la absorción de zinc y productividad de los cultivos, especialmente los cereales que tienen alta demanda de este nutriente. El objetivo de este estudio es evaluar los métodos de aplicación de Zn en el suelo, el estado nutricional y el rendimiento de maíz. Para ello, se realizó un experimento en FCAV/UNESP, Jaboticabal en Oxisol arcilloso (Zn-DTPA: 0,5 mg dm-3), el maíz (híbrido de impacto simple) de diciembre a mayo de 2009. Se aplicaron nueve tratamientos con tres dosis de Zn en forma localizada (en las crestas) y tres dosis de Zn mediante la incorporación en el suelo (0-20 cm), foliar, las semillas y el control de la aplicación (sin Zn). Los tratamientos se dispusieron en un diseño de bloques al azar con cuatro repeticiones. Independientemente del método, la aplicación de Zn promovió mayores niveles de zinc mayor acumulación en el suelo y en el aire, así como aumento de Zn en el grano. Sin embargo, no afectó el estado nutricional y el rendimiento de maíz. La aplicación de Zn resultó en un incremento de la absorción de zinc por las plantas y el rendimiento de maíz en comparación con la aplicación de Zn a la semilla de la planta o forma de hoja.

O conhecimento sobre o crescimento e o acúmulo de nutrientes em hipobiotos de caramboleira permite melhor eficiência da adubação na produção de hipobiotos (porta-enxertos). Objetivou-se determinar o crescimento e o acúmulo de nutrientes em hipobiotos de caramboleira cultivada em solução nutritiva. O experimento constituiu de cinco tratamentos, referentes aos tempos de coleta 25; 50; 75; 100 e 125 dias após o transplantio, dispostos em delineamento inteiramente casualizado em seis repetições. As plantas utilizadas foram obtidas de sementes de frutos de caramboleira 'Malásia', cultivadas em vasos com solução nutritiva. Nos diferentes órgãos dos hipobiotos (folhas, caule e raízes), avaliou-se o crescimento e o acúmulo de nutrientes e os índices nutricionais, a cada 25 dias. O ponto de enxertia (6 mm) foi atingido aos 110 dias após o transplantio. A ordem decrescente dos nutrientes acumulados em cada hipobioto produzido é de (em mg por planta): N = 634; K = 368; Ca = 152; Mg = 106; S = 98; P = 88 (em µg por planta) de: Fe = 2.963; Mn = 2.165; B = 722; Zn =780, e Cu = 96. O acúmulo médio de nutrientes é maior nas folhas > caule = raízes. O período de maior exigência de nutrientes pelos hipobiotos é compreendido entre 25-75 dias após o transplantio. As diferentes taxas de acumulação líquida dos nutrientes, nas diferentes partes da caramboleira, nem sempre acompanham a taxa de acumulação de nutrientes do respectivo órgão.

Knowledge of the growth of, and nutrient accumulation in rootstock of the star fruit leads to a more efficient fertilization in the production this rootstock. The objective was to determine the growth of, and nutrient accumulation in rootstock of the star fruit when grown in a nutrient solution. The experiment consisted of five treatments, related to the period of collection: 25; 50; 75; 100 and 125 days after transplanting, arranged in a completely randomized design with six replications. The plants used were obtained from seeds of the fruit of the 'Malaysia' carambola, grown in pots with a nutrient solution. The growth, accumulation of nutrients, and nutritional indices of different organs of the rootstock (leaves, stems and roots) were assessed every 25 days. The grafting point (6 mm) was reached at 110 days after transplanting. In decreasing order, the nutrients accumulated in each rootstock produced were (mg per plant): N = 634, K = 368, Ca =152, Mg = 106, S = 98, P = 88, and (mg per plant): Fe = 2,963, Mn = 2,165, B = 722;Zn = 780 and Cu = 96. The average accumulation of nutrients was higher in the leaves > stems = roots. The period of greatest nutrient demand by the rootstock occurred between 25-75 days after transplanting. The different net rates of accumulation of nutrients in the various parts of the star fruit do not always follow the rate of nutrient accumulation in the respective organ.

Para o arroz irrigado, poucos trabalhos utilizam métodos de diagnose foliar desenvolvidos para as condições locais de clima, solo ou cultivares. O objetivo deste trabalho foi avaliar os métodos da Diagnose da Composição Nutricional e da Chance Matemática na definição dos padrões nutricionais de lavouras arrozeiras do Estado do Rio Grande do Sul. Resultados de produtividade de grãos e teores foliares de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn e Mo de 356 lavouras arrozeiras cultivadas sob sistema de irrigação por inundação foram utilizados para a determinação das faixas de suficiência calculadas pelo método da Chance Matemática. As faixas de suficiência foram comparadas com valores críticos propostos pela literatura e com o intervalo de confiança do teor médio dos nutrientes em lavouras consideradas nutricionalmente equilibradas, identificadas pelo método Diagnose da Composição Nutricional. Observou-se pouca concordância entre os valores das faixas de suficiência indicados pelos métodos da Chance Matemática e da Diagnose da Composição Nutricional e os respectivos valores indicados na literatura. A faixa de teores foliares adequados, consistentes com maior produtividade média das lavouras arrozeiras, foi indicada ser de 23 a 28 g kg-1 para N; 11 a 14 g kg-1 para K; 1,4 a 2,0 g kg-1 para S; 6 a 12 mg kg-1 para B; e 70 a 200 mg kg-1 para Fe. Para os teores foliares de P, Ca, Mg, B, Cu, Mn e Zn e Mo nenhuma das faixas adequadas testadas indicou capacidade para distinguir as lavouras arrozeiras quanto à produtividade média.

For rice, few studies use foliar analysis methods developed for local conditions of climate, soil or cultivars. The purpose of this study was to evaluate the methods of Compositional Nutrient Diagnosis and of Mathematical Chance to define nutritional standards for rice fields in Rio Grande do Sul state, Brazil. Data of 356 irrigated rice fields for grain yield and foliar contents (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn, and Mo) were used to calculate the sufficiency ranges by the Mathematical Chance method. The sufficiency ranges were compared with critical values proposed in the literature and with the confidence interval of the average nutrient contents of nutritionally balanced crops identified by the Compositional Nutrient Diagnosis method. There was little agreement between the sufficiency ranges indicated by the methods of Mathematical Chance and Compositional Nutrient Diagnosis and the respective values in the literature. The appropriate range of foliar contents, consistent with highest average yield of rice fields, was 23-28 g kg-1 for N; 11-14 g kg-1 for K; 1.4-2.0 g kg-1 for S; 6-12 mg kg-1 for B; and 70-200 mg kg-1 for Fe. For the contents of P, Ca, Mg, B, Cu, Mn, Zn, and Mo none of the tested ranges allowed to discriminate rice yield.

Na colheita mecanizada sem o uso de fogo ocorre deposição de palhada na superfície do solo, a qual pode ser reciclada e reduzir a adubação potássica para a cana-de-açúcar, em relação à cana queimada, o que pode refletir em menor custo de produção. Objetivou-se avaliar o efeito da aplicação de potássio no desenvolvimento inicial da soqueira de primeiro corte da cana-de-açúcar (variedade SP 89-1115), em sistema de colheita sem despalha a fogo. O experimento foi instalado em uma área de primeira soqueira de cana-de-açúcar, cultivada em Latossolo Vermelho, textura argilosa. Os tratamentos foram constituídos por cinco doses de K2O (0 kg ha-1; 32,5 kg ha-1; 65,0 kg ha-1; 130,0 kg ha-1; e 195,0 kg ha-1), na forma de KCl, aplicado em 2009, dispostos em blocos casualizados e com cinco repetições. As variáveis de crescimento avaliadas foram: número de perfilhos, altura de planta e diâmetro de colmo, aos 120 dias após o brotamento. A aplicação de potássio proporcionou incremento com ajuste linear do teor de potássio no solo, nas camadas 0-0,20 m e 0,20-0,40 m de profundidade, atingindo 0,18 cmol c dm-3 e 0,12 cmol c dm-3, respectivamente, para a maior dose de K. A aplicação de K não afetou o número de perfilhos e diâmetro de colmo, mas influenciou a altura, atingindo maior valor na dose de 195,0 kg ha-1 de K2O.

In the mechanized harvesting without the use of fire, there is deposition of straw on the soil surface, which may be recycled and reduce the potassium fertilization for sugarcane, if compared to the burned sugarcane, what may reflect in a lower production cost. This study aimed to evaluate the potassium application effect in the early development of first cutting sugarcane ratoon (SP 89-1115), in an unburned harvesting system. The experiment was installed in a first sugarcane ratoon area, in a clay Oxisol. The treatments consisted of five K2O doses (0 kg ha-1, 32.5 kg ha-1, 65.0 kg ha-1, 130.0 kg ha-1, and 195.0 kg ha-1), as KCl, applied in 2009, in a randomized blocks design with five replications. The growth variables measured were number of tillers, plant height, and stem diameter, 120 days after budding. The potassium application provided a linear increase in the soil potassium content, at the 0-0.20 m and 0.20-0.40 m depth layers, reaching, respectively, 0.18 cmol c dm-3 and 0.12 cmol c dm-3, for the highest K dose. The K fertilization did not affect the number of tillers and stem diameter, but it affected plant height, which reached its highest value at 195.0 kg ha-1 of K2O.