ABSTRACT: Studies on the effects of biochar and chicken manure on soil chemical properties and initial growth of rosewood under field conditions in the Amazon are rare; therefore, a field experiment was carried out to evaluate the effects of biochar, chicken manure, and mineral fertilizer on the chemical properties of the soil, nutrient concentrations in the leaves, and on the initial growth of rosewood (Aniba rosaeodora) grown in clay soil. The study was conducted in causal blocks, with five treatments (control, biochar, biochar plus chicken manure, biochar plus mineral fertilizer, and biochar plus chicken manure plus mineral fertilizer) and three replications. In general, we observed that the application of biochar and chicken manure, alone or in combination, increased soil pH, calcium, phosphorus, zinc, and manganese content, as well as foliar potassium and calcium concentrations. However, despite fertilization, we did not observe significant gains in the growth of A. rosaeodora seedlings until ten months after planting. The combination of biochar and chicken manure exhibited the greatest impact, and is therefore important for soil sustainability and plant development in tropical soils.

RESUMEN: Los estudios sobre el efecto del biocarbón y el estiércol de pollo sobre las propiedades químicas del suelo y el crecimiento inicial del palo de rosa en condiciones de campo en el Amazonas son escasos, por lo que se llevó a cabo un experimento de campo para evaluar los efectos del biocarbón, el estiércol de pollo y los fertilizantes minerales sobre las propiedades químicas, propiedades del suelo, concentraciones de nutrientes en las hojas y sobre el crecimiento inicial del palo de rosa (Aniba rosaeodora) cultivado en suelo arcilloso. El estudio se realizó en bloques causales, con cinco tratamientos (testigo, biocarbón, biocarbón y gallinaza, biocarbón y fertilizante mineral, biocarbón, gallinaza y fertilizante mineral) y tres repeticiones. Observamos que, en general, la aplicación de biocarbón y estiércol de pollo, solos o en combinación, aumentó el pH del suelo, los contenidos de calcio, fósforo, zinc y manganeso, así como las concentraciones foliares de potasio y calcio. Por otro lado, a pesar de la fertilización, no observamos ganancias significativas en el crecimiento de las plántulas de A. rosaeodora hasta diez meses después de la siembra. La combinación de biocarbón y estiércol de pollo mostró el mayor impacto y, por lo tanto, es un aliado importante para la sostenibilidad del suelo y el desarrollo de las plantas en suelos tropicales.

ABSTRACT Seaweed extract-based fertilizers are applied to mitigate the effects of stress on plants. In this study, we evaluated the effects of different concentrations of seaweed extract-based fertilizer and different irrigation depths on potato crops. The Ágata cultivar and the Markies cultivar were used to conduct two experiments simultaneously. A 4 × 4 experimental design was used, with four doses of seaweed extract-based fertilizer (0, 0.5, 1.0, and 4.0 L ha-1) and four irrigation depths (50%, 75%, 100%, and 125% of crop evapotranspiration); each treatment had three replicates. Leaves were collected 67 days after emergence to analyze macronutrients and micronutrients; additionally, the number of stems per plant and physiological variables were assessed. After harvesting, the number and weight of tubers in different classes were recorded. The differences in parameters among treatment groups were determined by analysis of variance using the F-test, and regression analysis was performed when a significant difference was recorded. The results showed that the contents of potassium, phosphorus, magnesium, and calcium in the leaves of the Ágata cultivar were below the optimal levels for the crop, irrespective of the irrigation level and the dose of seaweed extract-based fertilizer applied. The highest irrigation depths at 100% and 125% of crop evapotranspiration were associated with an increase in the number and weight of the large tubers of the Ágata and Markies cultivars. extractbased extract based plants study crops simultaneously 0, 0 (0 05 5 0.5 10 1 1.0 40 4. ha1 ha ha-1 50%, 50 (50% 75 75% 100 125 evapotranspiration) replicates 6 micronutrients additionally assessed harvesting recorded Ftest, Ftest F test, test F-test potassium phosphorus magnesium cultivars ( 0. 1. ha- 50% (50 7 12 (5

RESUMO Para mitigar os efeitos do estresse nas plantas, têm sido aplicados fertilizantes foliares à base de extrato de algas marinhas. Objetivou-se avaliar os efeitos de diferentes concentrações de fertilizante à base de extrato de algas marinhas e lâminas de irrigação na cultura da batata. Dois experimentos foram conduzidos simultaneamente, um com a cultivar Ágata e outro com a cultivar Markies. O delineamento experimental utilizado foi 4 × 4, com quatro doses de fertilizante à base de extrato de algas marinhas (0; 0,5; 1,0 e 4,0 L ha-1) e quatro lâminas de irrigação (50%, 75%, 100% e 125% da evapotranspiração da cultura), com três repetições. Aos 67 dias após a emergência foram coletadas folhas para análise de macro e micronutrientes e, também avaliaram-se: número de hastes por planta e variáveis fisiológicas. Após a colheita, avaliaram-se: número e peso dos tubérculos de diferentes classes. Os dados foram submetidos à análise de variância por meio do teste F e análise de regressão foi realizada quando houve diferença significativa. Os teores de potássio, fósforo, magnésio e cálcio nas folhas da cultivar Ágata ficaram abaixo dos níveis ótimos para a cultura, independente do nível de irrigação e da da dose de fertilizante aplicado. O fertilizante reduziu os efeitos do estresse hídrico, aumentando a eficiência fotoquímica das plantas de batata Markies. As maiores lâminas de irrigação em 100% e 125% da evapotranspiração da cultura levaram ao aumento do número e peso de tubérculos grandes para as cultivares Ágata e Markies. Objetivouse Objetivou se simultaneamente Markies 0 (0 0,5 05 5 10 1 1, 40 ha1 ha ha-1 50%, 50 (50% 75 75% 100 125 , cultura) repetições 6 avaliaramse avaliaram avaliaram-se fisiológicas colheita classes significativa potássio fósforo aplicado hídrico ( 0, ha- 50% (50 7 12 (5

Resumo As orquídeas são uma das plantas decorativas florais mais populares. Dentre as diversas espécies de orquídeas, Phalaenopsis sp. ou a moon orchid é popular por causa de sua cor, formato e tamanho distintos. No entanto, as orquídeas apresentam taxa de crescimento lenta devido à sua longa fase juvenil; portanto, é necessária modificação da técnica de cultivo para impulsionar seu crescimento, ou seja, sombreamento e aplicação de fertilizantes. Esta pesquisa foi realizada com o objetivo de obter a melhor porcentagem de sombra e concentração de fertilizante para aumentar o crescimento da moon orchid. O experimento foi conduzido de junho a dezembro de 2022 na estufa de Bale Tatanan Padjadjaran, Faculdade de Agricultura, Universitas Padjadjaran, Jatinangor, Sumedang, Jawa Barat. O experimento utilizou o delineamento de parcelas subdivididas com oito tratamentos de sombra e fertilizantes. As plantas foram cultivadas em duas intensidades de sombreamento, 60% e 70%, e posteriormente tratadas com quatro concentrações diferentes de compostos fertilizantes foliares completos (1, 2, 3 e 4 g L-1). Os resultados mostraram que 60% de sombra combinada com 2 g L-1 de fertilizante foliar aumentou significativamente a área foliar e o comprimento da raiz, enquanto 70% de sombra combinada com 4 g L-1 aumentou significativamente a área foliar, número de raízes e o CCI da moon orchid. populares sp cor distintos entanto juvenil portanto seja 202 Padjadjaran Agricultura Jatinangor Sumedang Barat 60 70 1, 1 (1 L1. L1 L . L-1) L- raiz 20 6 7 (

Abstract Orchid plants are one of the most popular floral decorative plants. Among the several species of orchids, Phalaenopsis sp. or moon orchid is popular because of its distinctive color, shape, and size. However, orchids have a slow growth rate due to their long juvenile phase; thus, culture technique modification is required to boost their growth, i.e., shading and fertilizer application. This research was carried out to obtain the best shade percentage and fertilizer concentration to increase the growth of moon orchid. The experiment was conducted from June to December 2022 at the greenhouse of Bale Tatanan Padjadjaran, Faculty of Agriculture, Universitas Padjadjaran, Jatinangor, Sumedang, Jawa Barat. The experiment used a split-plot design of eight shade and fertilizer treatments. The plants were cultivated in two shading intensities, namely 60% and 70%, then treated with four different complete foliar fertilizer compound concentrations (1, 2, 3, and 4 g L-1). The results showed that 60% shade combined with 2 g L-1 of foliar fertilizer significantly increased the leaf area and root length, whereas 70% shade combined with 4 g L-1 significantly increased the leaf area, root number and CCI of moon orchid. sp color shape size However phase thus ie i e i.e. application 202 Padjadjaran Agriculture Jatinangor Sumedang Barat splitplot split plot treatments intensities 60 70 1, 1 (1 3 L1. L1 L . L-1) L- length i.e 20 6 7 (

Abstract Two field experiments were conducted during 2019 and 2020 summer seasons at the experimental station of national research center, Al-Nubaryia district, El-Behaira Governorate, Egypt, to study the effect of Phenyl alanine and Aspartic acid foliar fertilizers at rates of (0.0, 50, 75 and 100 ppm) on morphological characters, photosynthetic pigments, seed yield and its components as well as seed quality of groundnut grown under sandy soil. Results indicated superiority of aspartic acid over phenyl alanine on increasing different growth parameters, chlorophyll b, biological and seed yields/plant, biological, seed and oil yields (kg/fed.), % of carbohydrate in peanut seeds. Meanwhile, phenyl alanine was superior on increasing carotenoids, indole acetic acid, phenolics, free amino acids, flavonoids, Lycopene, β-Carotene contents, antioxidant activity expressed as (1,1-diphenyl-2-picrylhydrazyl DPPH %) and shilling percentage. In addition, aspartic acid and phenyl alanine with various levels caused significant increases in growth and seed yield quantity and quality of peanut plants through increases in photosynthetic pigments, indole acetic acid, phenolics and free amino acids contents. Aspartic acid was more effective than phenyl alanine, Foliar treatment with 100 mg/L aspartic acid increased oil yield (700.36 over 568.05 ton/fed.) and seed yield (1531.98 over 1253.49 kg/fed.). Finally, it can conclude that using aspartic acid and phenyl alanine as foliar treatment improved growth and yield of ground nut plants under sandy soil. 201 202 center AlNubaryia Al Nubaryia district ElBehaira El Behaira Governorate Egypt 0.0, 00 0 (0.0 50 7 10 ppm characters pigments soil parameters b yieldsplant plant yields/plant kg/fed., kgfed kg/fed. , kg fed (kg/fed.) seeds Meanwhile carotenoids flavonoids Lycopene βCarotene β Carotene contents 1,1diphenyl2picrylhydrazyl 11diphenyl2picrylhydrazyl diphenylpicrylhydrazyl 1,1 diphenyl 2 picrylhydrazyl 1 percentage addition mgL mg L 700.36 70036 700 36 (700.3 56805 568 05 568.0 ton/fed. tonfed ton 1531.98 153198 1531 98 (1531.9 125349 1253 49 1253.4 kg/fed.. . kg/fed.) Finally 20 0.0 (0. 5 kg/fed (kg/fed. 1diphenyl2picrylhydrazyl 11 1, 700.3 7003 70 3 (700. 5680 56 568. ton/fed 1531.9 15319 153 9 (1531. 12534 125 4 1253. 0. (0 (kg/fed 700. (700 1531. 15 (1531 12 ( (70 (153 (7 (15 (1

Resumo Dois experimentos de campo foram conduzidos durante as temporadas de verão de 2019 e 2020 na estação experimental do centro nacional de pesquisa, distrito de Al-Nubaryia, província de El-Behaira, Egito, para estudar o efeito de fenilalanina e fertilizantes foliares de ácido aspártico a taxas de (0,0, 50, 75 e 100ppm) em caracteres morfológicos, pigmentos fotossintéticos, rendimento de sementes e seus componentes, bem como qualidade de sementes de amendoim cultivadas em solo arenoso. Os resultados indicaram superioridade do ácido aspártico sobre a fenilalanina no aumento de diferentes parâmetros de crescimento, clorofila b, rendimento biológico e de sementes/planta, biológico, de sementes e óleo (Kg/alimentado), porcentagem de carboidratos em sementes de amendoim. Enquanto isso, a fenilalanina foi superior no aumento de carotonóides, ácido indolacético, fenólicos, aminoácidos livres, flavonóides, licopeno, teores de B-caroteno, atividade antioxidante expressa como (1,1-difenil-2-picrilhidrazil DPPH%) e porcentagem de shilling. Além disso, ácido aspártico e fenilalanina com vários níveis causaram aumentos significativos no crescimento e produção de sementes, quantidade e qualidade de plantas de amendoim através de aumentos nos teores de pigmentos fotossintéticos, ácido indolacético, fenólicos e aminoácidos livres. O ácido aspártico foi mais eficaz que a fenilalanina. O tratamento foliar com 100 mg/L de ácido aspártico aumentou o rendimento de óleo (700,36 sobre 568,05 ton./alimentado) e o rendimento de sementes (1531,98 sobre 1253,49 kg/alimentação). Finalmente, pôde-se concluir que o uso de ácido aspártico e fenilalanina como tratamento foliar melhorou o crescimento e a produção de plantas de amendoim em solo arenoso. 201 202 pesquisa AlNubaryia, AlNubaryia Al Nubaryia, Nubaryia Al-Nubaryia ElBehaira, ElBehaira El Behaira, Behaira El-Behaira Egito 0,0, 00 0 (0,0 50 7 100ppm ppm morfológicos fotossintéticos componentes arenoso b sementesplanta planta sementes/planta Kg/alimentado, Kgalimentado Kg/alimentado , Kg alimentado (Kg/alimentado) isso carotonóides indolacético livres flavonóides licopeno Bcaroteno, Bcaroteno B caroteno, caroteno B-caroteno 1,1difenil2picrilhidrazil 11difenil2picrilhidrazil difenilpicrilhidrazil 1,1 difenil 2 picrilhidrazil 1 DPPH% DPPH shilling disso 10 mgL mg L 700,36 70036 700 36 (700,3 56805 568 05 568,0 ton./alimentado tonalimentado ton 1531,98 153198 1531 98 (1531,9 125349 1253 49 1253,4 kg/alimentação. kgalimentação kg/alimentação . kg alimentação kg/alimentação) Finalmente pôdese pôde se 20 0,0 (0, 5 (Kg/alimentado 1difenil2picrilhidrazil 11 1, 700,3 7003 70 3 (700, 5680 56 568, 1531,9 15319 153 9 (1531, 12534 125 4 1253, 0, (0 700, (700 1531, 15 (1531 12 ( (70 (153 (7 (15 (1

RESUMEN La fertilización foliar es una estrategia que permite complementar la nutrición de los cultivos cuando algún factor del suelo limita la absorción de nutrientes por la raíz. El objetivo del estudio fue evaluar la efectividad de momentos y fuentes de aplicación foliar de Ca, B y Zn en el rendimiento y rentabilidad del cacao nacional. Los tratamientos consistieron en tres fuentes foliares de Ca, B y Zn (sales, quelatos y aminoquelatos) y tres tiempos de aplicación foliar (06:00 - 08:00, 11:00 - 13:00 y 16:00 - 18:00 horas). Además, se incluyó un tratamiento control que solo recibió fertilización edáfica. Se registró el rendimiento de grano (kg ha-1) y beneficio económico neto de la fertilización foliar (USD ha-1). Los datos fueron analizados a través del ANOVA y la prueba de Tukey (α = 0,05). El rendimiento de grano fue influenciado significativamente (p < 0,05) por las fuentes foliares y los tiempos de aplicación foliar. Los aminoquelatos permitieron alcanzar el mayor rendimiento de grano, con un incremento de 198, 289 y 440 kg, con relación a los tratamientos con quelatos, sales y control, respectivamente. Las aplicaciones foliares en la mañana y tarde, mostraron mayor rendimiento de grano con relación a la aplicación del medio día, e incrementaron el rendimiento en un 20,46 y 20,06% con relación al tratamiento control. El mayor beneficio económico neto de la fertilización foliar se produjo con los aminoquelatos aplicados en horas de la mañana y tarde, con 442 y 418 USD ha-1, respectivamente. La aplicación foliar de aminoquelatos de Ca, B y Zn es una estrategia efectiva para incrementar rendimiento y rentabilidad del cacao nacional.

ABSTRACT Foliar fertilization is a strategy that allows complemented crop nutrition when soil factors limit the absorption of nutrients by the roots. The aim of the research was to evaluate the effectiveness of foliar application times and sources of Ca, B, and Zn in the yield and profitability of national cocoa. The treatments consisted of three foliar sources of Ca, B, and Zn (salts, chelates, and aminochelates) and three foliar application times (06:00 - 08:00, 11:00 - 13:00 and 16:00 - 18:00 hours). In addition, a control treatment that only received edaphic fertilization was included. Data were analyzed through ANOVA and Tukey's test (α = 0.05). Grain yield (kg ha-1) and net economic benefit of foliar fertilization (USD ha-1) were recorded. Grain yield was significantly (p < 0.05) influenced by foliar sources and foliar application times. The aminochelates allowed reaching the highest grain yield, with an increase of 198, 289, and 440 kg, in relation to the treatments with chelates, salts, and control, respectively. Foliar applications in the morning and afternoon showed higher grain yield in relation to the noon application, and increased yield by 20.46 and 20.06% in relation to the control treatment. The greatest net economic benefit of foliar fertilization occurred with aminochelates applied in the morning and afternoon, with 442 and 418 USD ha-1, respectively. The foliar application of aminochelates of Ca, B, and Zn is an effective strategy to increase yield and profitability of Ecuador’s national cocoa.

Abstract Introduction: Seaweed extracts have biostimulant activities that improve growth and yield in many crops, and can improve mineral absorption. Objective: to evaluate the effects of foliar spray of seaweed extract and fertilizers (treatments: seaweed extract (SE); fertilizers (FF); seaweed extract+fertilizers (SE+FF); and control-C) on the yield and quality of sweet pepper grown under greenhouse conditions. Methods: The crop was managed in a coconut fiber substrate and with fertigation. Evaluated variables were: number of fruits per plant, fruit weight (g), yield (ton/ha), percentage of total soluble solids (°Brix), chlorophyll content (atLEAF), leaf area (cm2), leaf dry weight (g), specific leaf weight (mg/cm2), plant height (cm), and stem diameter (mm). Treatments were applied from 14 days after transplant (ddt), and were carried out weekly until the end of the trial (154 ddt). Results: Treatments SE and SE+FF produced a higher number of commercial and total fruits per plant, as well as higher commercial and total yields when compared to treatments FF and C. The SE+FF treatment produced a greater fruit weight, compared to treatment C, both at a commercial and total level. No significant differences between treatments were observed for the following variables: leaf area, leaf dry weight, leaf specific weight, plant height and stem diameter. Conclusion: The use of the seaweed extract (SE) produced the highest total and commercial yield at the lowest cost, and thus its utilization is recommended under the trial conditions; on the other hand, the application of foliar fertilizers (FF) under the same conditions did not improve neither the yield of sweet peppers nor their quality.

Resumen Introducción: Los extractos de algas marinas tienen actividad bioestimulante que mejoran el crecimiento y rendimiento en muchos cultivos, y pueden mejorar la absorción de minerales. Objetivo: Evaluar el efecto de la aplicación foliar de extracto de algas y fertilizantes (tratamientos: extracto de algas (A); fertilizantes (FF); extracto de algas+fertilizantes (A+FF); y testigo-T) sobre el rendimiento y calidad del pimiento cultivado bajo invernadero. Métodos: El cultivo se manejó en sustrato de fibra de coco y con fertirrigación. Las variables evaluadas fueron: número de frutos por planta, peso del fruto (g), rendimiento (ton/ha), porcentaje de sólidos solubles totales (°Brix), contenido de clorofila (atLEAF), área foliar (cm2), peso seco foliar (g), peso específico foliar (mg/cm2), altura de planta (cm), y diámetro de tallo (mm). Los tratamientos se aplicaron a partir de los 14 días después del trasplante (ddt), y se realizaron en forma semanal hasta el final del ensayo (154 ddt). Resultados: Los tratamientos A y A+FF produjeron una cantidad superior de frutos comerciales y totales por planta, y un rendimiento comercial y total superior, en comparación con FF y T. El tratamiento A+FF produjo frutos con mayor peso, en comparación con T, tanto a nivel comercial como total. No se hallaron diferencias significativas entre tratamientos para las siguientes variables: área foliar, peso seco foliar, peso específico foliar, altura de planta y diámetro de tallo. Conclusión: El uso del extracto de algas (A) produjo el mayor rendimiento total y comercial al menor costo, por lo que se recomienda su uso; además, la aplicación de fertilizantes foliares (FF) no mejoró ni el rendimiento ni la calidad en el cultivo de pimiento, bajo las condiciones del ensayo.

ABSTRACT Maize (Zea mays L.) is a worldwide staple food, cultivated using mainly mineral fertilizers and other soil degradation practices. Biofertilizers are an alternative to help limit soil degradation and improve crop productivity. This research aims to determine maize response to foliar applications of liquid organic fertilizers. A completely randomized block design with five treatments was used: hydrolyzed fish (T1), Neem oil (T2), digested liquid bovine manure (T3), NPK fertilization (T4), and the control (T5). The results show that maize plants with conventional fertilization reached the lowest number of days to male (51.50) and female flowering (53.50), and the highest ear height (101.25 cm). Maize plants with NPK fertilization and those receiving liquid bovine manure recorded the highest values in extended ear length (18.17 and 16.44 cm, respectively); number of grains per row (32 and 29 units, respectively); and grain yield (7.32 and 6.95 t·ha-1 respectively). There were no significant differences in the number of rows per ear. The highest cost-effectiveness was obtained with liquid bovine manure (54.01%), followed by NPK (52.61%). In conclusion, foliar applications of digested liquid bovine manure result in similar yields and higher cost-effectiveness to those obtained by conventional NPK fertilization.

RESUMEN El maíz (Zea mays L.) es un insumo básico en la alimentación a nivel mundial que se cultiva empleando principalmente fertilizantes minerales y prácticas que contribuyen a la degradación de los suelos. Los abonos orgánicos son una alternativa que contribuye a limitar la degradación de los suelos y a mejorar la productividad de los cultivos. El objetivo de la investigación fue determinar la respuesta del maíz a la aplicación de abonos foliares orgánicos líquidos y estimar la rentabilidad económica de cada tratamiento. Se usó un diseño de bloques completamente al azar con cinco tratamientos: pescado hidrolizado (T1), aceite de Neem (T2), estiércol líquido bovino digerido al 60% (T3), fertilización NPK (T4) y testigo (T5). Los resultados indicaron que las plantas de maíz con fertilización NPK alcanzaron el menor número de días a la floración masculina (51,50) y femenina (53,50), y la mayor altura de mazorca (101,25 cm). Las que recibieron fertilización NPK y las que recibieron estiércol líquido de bovino alcanzaron los valores más altos en longitud de mazorca (18,17 y 16,44 cm, respectivamente), cantidad de granos por hilera (32 y 29 unidades, respectivamente) y rendimiento de grano (7,32 y 6,95 t·ha-1, respectivamente). No se presentaron diferencias significativas en el número de hileras en mazorca. La mayor rentabilidad se obtuvo con estiércol líquido bovino (54,01%), seguido de NPK (52,61%). Se concluye que el estiércol líquido de bovino aplicado de manera foliar permite alcanzar rendimientos cercanos y rentabilidad superior a los obtenidos con fertilización convencional NPK.

RESUMO Este estudo baseia-se no princípio de que índices de vegetação (IVs), derivados do modelo de cores RGB obtidos de imagens digitais, podem ser usados para caracterizar assinaturas espectrais e classificar pastos de Brachiaria brizantha cv. Xaraés segundo o status de nitrogênio (N). A partir de dados colorimétricos obtidos de imagens de lâminas foliares adquiridas em campo, três redes neurais artificiais foram avaliadas quanto ao desempenho na classificação do status N: Feedforward Backpropagation (FFBP), Cascade Forward Backpropagation (CFBP) e função de Base Radial (RBFNN). Quatro taxa s de fertilização nitrogenada foram aplicadas para gerar contrastes no teor de N nos tecidos das plantas. As folhas mais jovens completamente expandidas de 60 perfilhos foram destacadas das plantas a cada ciclo de rebrotação de 28 dias, sendo as imagens das folhas e teor de N foliar determinados. As amostras foram classificadas em deficientes (> 17 g N kg-1 de matéria seca (MS)), moderadamente deficientes (de 17,1 a 20,0 g N kg-1 MS) e suficiente (> 20,1 g N kg-1 MS). Os IVs foram selecionados pela análise de componentes principais e o desempenho das redes avaliados pela acurácia. As acurácias nas classificações obtidas pelas redes foram de 88%, 86% e 79% para FFBP, CFBP e RBFNN, respectivamente, indicando que as assinaturas espectrais podem ser determinadas a partir de imagens adquiridas em campo. Assim, o método proposto pode ser utilizado para desenvolver um software de monitoramento do status de N em tempo real, fornecendo uma ferramenta rápida e econômica para definir o momento e quantidade de fertilizantes nitrogenados, conforme demanda da pastagem.

ABSTRACT This study is based on the principle that vegetation indexes (VIs), derived from the RGB color model obtained from digital images, can be used to characterize spectral signatures and classify Brachiaria brizantha cv. Xaraés according to nitrogen status (N). From colorimetric data obtained from leaf blade images acquired in the field, three artificial neural networks were evaluated according to the performance in the classification of N status: Feedforward Backpropagation (FFBP), Cascade Forward Backpropagation (CFBP) and Radial Base function (RBFNN). Four N fertilization rates were applied to generate contrasting N contents in the plants. The youngest completely expanded leaves from 60 tillers were detached at each regrowth cycle of 28 days, thus their images and leaf N content were obtained. Samples were then classified as deficient (>17 g N kg-1 leaf dry matter (DM), moderately deficient (from 17.1 to 20.0 g N kg-1 DM), and sufficient (> 20.1 g N kg-1 DM). The VIs were selected by principal component analysis and the performance of the networks evaluated by the accuracy. The accuracy in classification obtained by the networks were 88%, 86% and 79% for FFBP, CFBP and RBFNN, respectively, indicating that the spectral signatures can be determined from images acquired in the field. So, the proposed method could be used to develop a software that aims to monitor the status of N in real time, providing a fast and inexpensive tool for defining the time and the amount of N fertilizer, according to the pasture demand.

Resumo O uso contínuo de fertilizantes químicos diminui gradualmente o rendimento e a qualidade das culturas, e esses efeitos adversos podem ser reduzidos com a adoção de novas práticas sustentáveis, como o uso de esterco, biofertilizantes e nanofertilizantes. A informação limitada existe sobre a aplicação de micróbios Trichoderma harzianum e Bacillus thuringiensis para melhorar o crescimento de mudas de limão, fisiologia e formação de frutos. Portanto, o presente estudo tem como objetivo avaliar os efeitos da mistura de micróbios T. harzianum e B. thuringiensis com baixo nível de fertilizante inorgânico (NPK) no crescimento, desenvolvimento e qualidade de frutos de limau nipis (limão-chave). Os meios de cultivo de mudas de limão foram inoculados durante o transplante com T. harzianum e B. thuringiensis em vários fertilizantes NPK sob condições de polybag. As mudas foram cultivadas em torno de 10 meses após a inoculação com biofertilizantes seguidas de delineamento em blocos completos randomizados (RCBD) com 5 repetições. Os resultados mostraram que T. harzianum com 50 g de tratamento NPK (T2) aumentou a altura de plântulas, número de ramos, altura de folha, área do solo e taxa de crescimento absoluto (AGR) em 50,12%, 107,84%, 17,91%, 17,91%, 116,93% e 56,02%, respectivamente, em relação ao tratamento controle. O número de folhas (60,82%), área foliar (42,75%), diâmetro do caule (27,34%), área foliar específica (SLA) (39,07%), índice de área foliar (IAF) (54,40%) e taxa absoluta de crescimento para número de folhas (73,86%), área foliar (306,85%) e diâmetro do caule (46,8%) das mudas de limão aumentaram significativamente com B. thuringiensis mais 50 g de tratamento NPK (T3). As aplicações de B. thuringiensis com 25 g de tratamento com fertilizante NPK (T5) aumentaram a massa fresca da folha (LFW), massa seca da folha (LDW), teor de umidade da folha (LMC), peso específico da folha (SLW), taxa de crescimento relativo da folha (RGR) e teor de clorofila em 96,45%, 56,78%, 13,60%, 24,76%, 45,45% e 16,22%, respectivamente, em relação ao grupo controle. Além disso, o tratamento T5 aumentou o número de frutos, peso individual do fruto, diâmetro do fruto, dimensão do fruto, sólidos solúveis totais foliares (SST) e teor de SST do fruto do limão em 81,81%, 55,52%, 43,54%, 25,69%, 89,47% e 70,78% em relação ao tratamento controle. Além disso, a inoculação no solo de B. thuringiensis aumentou significativamente a relação polpa/casca e o teor de suco de frutos de limão. A partir deste estudo, pode-se concluir que a inoculação no solo de T. harzianum e B. thuringiensis com 25-50% de NPK durante o transplante melhorou o crescimento das plantas, a fisiologia e a qualidade dos frutos de limau nipis.

Abstract Continuous use of chemical fertilizers gradually shrinks the crop yield and quality, and these adverse effects can be reduced by adopting new sustainable practices such as the use of manure, biofertilizers, and nano fertilizers. Limited information is existed on the application of Trichoderma harzianum and Bacillus thuringiensis microbes to improve lemon seedlings growth, physiology, and fruit formation. Therefore, the current study is aimed to evaluate the effects of T. harzianum and B. thuringiensis microbes mixing with low levels of inorganic fertilizer (NPK) on the plant growth, development, and quality of limau nipis (key lemon) fruits. The lemon seedlings growing media were inoculated during transplanting with T. harzianum and B. thuringiensis at various NPK fertilizers under polybagged conditions. The seedlings were grown around eighteen (18) months after inoculation with biofertilizers followed by Randomized Complete Block Design (RCBD) with five (5) replications. The results showed that T. harzianum with 50 g of NPK treatment (T2) increased the seedling's height, branch number, leaf height, ground area, and absolute growth rate (AGR) plant height by 50.12%, 107.84%, 17.91%, 17.91%, 116.93%, and 56.02%, respectively, over the control treatment. The number of leaves (60.82%), leaf area (42.75%), stem diameter (27.34%), specific leaf area (SLA) (39.07%), leaf area index (LAI) (54.40%), and absolute growth rate for leaf number (73.86%), leaf area (306.85%) and stem diameter (46.8%) of lemon seedlings increased significantly with B. thuringiensis plus 50 g NPK treatment (T3). The applications of B. thuringiensis with 25 g NPK fertilizer treatment (T5) increased leaf fresh weight (LFW), leaf dry weight (LDW), leaf moisture content (LMC), specific leaf weight (SLW), leaf relative growth rate (RGR), and chlorophyll content by 96.45%, 56.78%, 13.60%, 24.76%, 45.45%, and 16.22%, respectively, over the control group. In addition, T5 treatment increased the fruits number, individual fruit weight, fruit diameter, fruit dimension, leaf total soluble solids (TSS), and fruit TSS content of lemon tress by 81.81%, 55.52%, 43.54%, 25.69%, 89.47%, and 70.78% compared to the control treatment. Furthermore, soil inoculation of B. thuringiensis significantly increased the pulp to peel ratio and juice content of lemon fruits. From this study, it can be concluded that soil inoculation of both T. harzianum and B. thuringiensis with 25-50% NPK during transplanting improved plant growth, physiology, and fruit quality of limau nipis trees.

RESUMO Valores de referência dos teores foliares são essenciais para avaliação nutricional das plantas. Objetivou-se estabelecer valores de referência nutricional para a bananeira ‘BRS Platina’ em solo de fertilidade construída, mediante a utilização dos métodos faixa de suficiência (SR), linha de fronteira (BL) e chance matemática (MCh), além do nível crítico obtido pela distribuição normal reduzida (CLz). O estudo foi realizado em Guanambi-BA, considerando teores de nutrientes e produtividades de experimento arranjado em blocos casualizados, esquema fatorial 5 x 6, cinco doses de K2O (0, 200, 400, 600 e 800 kg ha-1) supridas com fertilizantes para manejo orgânico e seis épocas de amostragem (210; 390; 570; 750; 930 e 1.110 dias após plantio), totalizando 90 parcelas. Parcelas de alta produtividade, ≥ 38,40 t ha-1 formaram a população de referência e ≥ 47,43 t ha-1 subpopulação de referência. Houve convergência entre os valores ótimos obtidos pelos métodos avaliados. Portanto, os valores de referência ajustados pelos métodos SR, BL, MCh e CLz podem ser usados com assertividade para interpretação da análise foliar da bananeira ‘BRS Platina’ em solos de fertilidade construída. Ademais, dentre esses, a MCh se destaca pois proporciona faixas ótimas mais estreitas.

ABSTRACT Reference values of leaf nutrient contents are essential for nutritional assessment of plants. The objective was to establish nutritional reference values for ‘BRS Platina’ banana in improved fertility soil, using the sufficiency range (SR), border Line (BL) and mathematical chance (MCh) methods, in addition to the critical level obtained by the reduced normal distribution (CLz). The study was carried out in Guanambi-BA, considering nutrient contents and yields of an experiment arranged in randomized blocks, 5 x 6 factorial scheme, with five doses of K2O (0, 200, 400, 600 and 800 kg ha-1) supplied with fertilizers for organic management and six sampling times (210; 390; 570; 750; 930 and 1,110 days after planting), totaling 90 plots. Plots with high yield, ≥ 38.40 t ha-1, formed the reference population and plots with yield ≥ 47.43 t ha-1 formed the reference subpopulation. There was convergence between the optimal values obtained by the methods evaluated. Therefore, the reference values adjusted by the SR, BL, MCh and CLz methods can be used with assertiveness to interpret the foliar analysis of the ‘BRS Platina’ banana in improved fertility soils. Furthermore, among these, MCh stands out as it provides narrower optimal ranges.

Abstract This study evaluated the structure of swards planted with Urochloa brizantha cv. BRS Paiaguas and BRS Piata under the eucalyptus shading system, fertilized via foliar at the beginning of the dry and rainy seasons. The experiment followed a randomized block design with a 4×2×2 (4 leaf fertilizer levels × 2 systems × 2 seasons) factorial arrangement. The results were analyzed using the GLIMMIX PROC of SAS University while means were compared by the T-test at 5%. Foliar fertilizer had a significant (P≤0.05) effect on cv. BRS Paiaguas stem mass under shading while the 3 and 6 L/ha levels produced the lowest (P≤0.05) masses. The forage and root masses were not significantly affected (P≥0.05) by the systems and seasons whereas the dead material mass was not influenced by the seasons. The shading system resulted in (P≤0.05) significantly lower dead material mass for both cultivars and higher (P≤0.05) leaf and stem masses for the cv. BRS Piata. In the rainy season, leaf and stem masses were greater (P≤0.05). Foliar fertilization up to 6 L/ha favored the stem control in cv. BRS Paiaguas under shading. The resulting masses of forage, dead material, and root allow concluding that the cultivars adapted well to the shading and dry season.

Resumen Este estudio evaluó la estructura de pastos sembrados con Urochloa brizantha cv. BRS Paiaguas y BRS Piata bajo el sistema de sombra de eucalipto, fertilizados vía foliar al inicio de las temporadas seca y lluviosa. El experimento siguió un diseño de bloques al azar con un arreglo factorial de 4×2×2 (4 niveles de fertilizantes foliares × 2 sistemas × 2 temporadas). Los resultados se analizaron utilizando el GLIMMIX PROC de la Universidad SAS, mientras que las medias se compararon mediante la prueba de t al 5 %. El fertilizante foliar tuvo un efecto significativo (P≤0.05) en la producción de brotes del cv. BRS Paiaguas bajo sombra, mientras que los niveles de 3 y 6 L/ha produjeron las menores masas (P≤0.05). Las masas del forraje y raíz fueron afectadas significativamente (P≥0.05) por los sistemas y las temporadas, mientras que la masa de la materia muerta no fue influenciada por las temporadas. El sistema de sombra resultó en una masa de la materia muerta significativamente menor (P≤0.05) para ambos cultivares y masas de hojas y tallos mayores (P≤0.05) para el cv. BRS Piata. En la temporada de lluvias, las masas de hojas y tallos fueron mayores (P≤0.05). La fertilización foliar con hasta 6 L/ha favoreció el control del tallo en el cv. BRS Paiaguas bajo sombra. Las masas resultantes de forraje, materia muerta y raíz permiten concluir que los cultivares se adaptaron bien a la sombra y a la temporada seca.

RESUMEN El experimento se llevó a cabo durante la temporada 2018 en la estación de investigación del College of Agriculture and Forestry (Universidad de Mosul, Irak), para investigar el efecto del polvo de rocas volcánicas (PRV) (0, 125, 250 g m-2) y el fertilizante hierro quelado Fe-EDTA (0, 100, 200 mg L-1) sobre la bacteria Rhizobium fabae y el crecimiento y rendimiento de dos variedades de haba (Vicia faba L.), Histal y Aquadulce. Se utilizó un diseño en bloques completos al azar con tres repeticiones y la diferencia mínima significativa (DMS) para hacer una comparación entre las medias a un nivel de significancia de 0.05. Los resultados mostraron que PRV 250 g m-2 obtuvo la media significativa más alta para las siguientes características: índice de área foliar (IAF), número de ramas por planta, contenidos foliares de clorofila y hierro, número de nódulos bacterianos efectivos por planta, peso de 100 semillas, rendimiento de la planta, y porcentaje de proteína en las semillas. Por otra parte, 200 mg L-1 Fe-EDTA obtuvo la media significativa más alta de todas las características para ambas variedades, excepto para el IAF y el número de ramas por planta. La aplicación de Fe-EDTA por planta no tuvo un efecto significativo sobre el contenido foliar de clorofila para ambas variedades ni sobre el porcentaje de proteína en las semillas para la variedad Aquadulce. La interacción del PRV 250 g m-2 con 200 mg L-1 Fe-EDTA logró la media significativa más alta para todas las características, a excepción de la altura de la planta.

ABSTRACT The experiment was conducted during the 2018 season at the research station of the College of Agriculture and Forestry (University of Mosul, Iraq) to investigate the effect of volcanic rock dust (VRD) (0, 125, 250 g m-2) and the fertilizer chelated iron Fe-EDTA (0, 100, 200 mg L-1) on the bacteria Rhizobium fabae, and the growth and yield of two broad bean (Vicia faba L.) varieties, Histal and Aquadulce. A randomized complete block design was used with three replicates and least significant difference (LSD) to compare means at a significance level of 0.05. Results showed that VRD 250 g m-2 obtained the highest significant mean for the following traits: leaf area index (LAI), number of branches per plant, leaf contents of chlorophyll and total iron, number of effective bacteria nodules per plant, 100-seed weight, plant yield, and percentage of protein in the seeds. On the other hand, 200 mg L-1 Fe-EDTA obtained the highest significant mean of all the traits for both varieties, except for LAI and number of branches per plant. The application of Fe-EDTA per plant had no significant effect on the leaf content of chlorophyll for both varieties and the percentage of protein in the seeds for variety Aquadulce. The interaction of VRD 250 g m-2 with 200 mg L-1 Fe-EDTA achieved the highest significant average for all the traits, except for plant height.

RESUMO O uso da fertigação como meio de suprimento das necessidades nutritivas das culturas é uma técnica amplamente difundida entre os produtores. Contudo, a necessidade de aprimoramento desta técnica se faz necessário devido, principalmente, aos riscos de contaminação dos recursos naturais. Assim, objetivou-se estudar a produtividade e os teores foliares de nutrientes do meloeiro e fertilidade do solo que apresenta alta concentração de potássio, quando fertigado com doses de nitrogênio e potássio na água de irrigação. Aplicaram-se cinco tratamentos dispostos em blocos casualizados com seis repetições. Os tratamentos consistiram nas combinações de concentrações, em mg L-1, de nitrogênio (N) e potássio (K) aplicadas na água de irrigação (0-0), (50-0), (50-54), (0-54) e (100-108). Foram avaliados os teores foliares de nutrientes do meloeiro aos 35 dias após o plantio, e a produtividade e a fertilidade do solo por ocasião da colheita. O meloeiro cultivado em solo com nível alto de K e aplicação de 18 kg ha-1 de N em fundação não aumentou a produção quando fertirrigado com nitrogênio e potássio. Embora teores de K, Fe e B variou entre as doses de N e K aplicadas as plantas não apresentaram deficiência nutricional. As aplicações de fertilizantes em doses crescentes contribuem para o acúmulo de sais no solo, aumentando o risco de salinização.

ABSTRACT The use of fertigation as a means of supplying the nutritional needs of crops is a technique widely used among producers. However, it is necessary to improve this technique due, mainly, to the risks of contamination of natural resources. Thus, the objective was to study the productivity and leaf contents of melon nutrients and soil fertility, which presents a high concentration of potassium, when fertigated with doses of nitrogen and potassium in the irrigation water. Five treatments were arranged in randomized blocks with six repetitions. Treatments consisted of combinations of concentrations, in mg L-1, of nitrogen (N) and potassium (K) applied in irrigation water (0-0), (50-0), (50-54), (0-54) and (100-108). The leaf concentrations of nutrients of melon were evaluated at 35 days after planting, and fruit yield and soil fertility at harvest time. The melon cultivated in soil with a high level of K and basal application of 18 kg ha-1 of N in the foundation did not increase production, when fertirrigated with nitrogen and potassium. Although the contents of K, Fe and B varied between the doses of N and K applied, the plants did not have nutritional deficiency. Fertilizer applications in increasing doses contribute to the accumulation of salts in the soil, increasing the risk of salinization.

Resumo Juniperus flaccida Schltdl. É uma espécie florestal muito importante que, em El Cardonal, Hidalgo, México, é fortemente atacada por Phoradendron juniperinum Engelm. O objectivo desta investigação foi avaliar a resposta dos ramais de J. flaccida em termos da sua biomassa, do seu estado nutricional e do da sua planta parasita, em relação às aplicações de nitrogénio (N), fósforo (P) e potássio (K), numa floresta natural de Juniperus flaccida. As doses e fontes de fertilizantes foram 0 e 1000; 0 e 300; e 0, 450 e 900 g de ureia de árvore 1; ácido fosfórico e sulfato de potássio, respectivamente. O desenho experimental utilizado foi completamente aleatório num arranjo fatorial 2X2X3, com seis réplicas. As análises do solo mostraram níveis baixos de N e P, e K suficiente no local. As aplicações individuais de N e P não tiveram um efeito significativo na biomassa, apesar de serem deficientes na área experimental. J. flaccida apresentou concentrações foliares de N, Mg, Cu, Mn e B mais elevadas do que P. juniperinum, e este último apresentou concentrações mais elevadas de P, K, Ca, Fe e Zn do que o seu hospedeiro. A aplicação de azoto diminuiu significativamente a concentração de K em P. juniperinum e influenciou a divisão do foliar P entre J. flaccida e P. juniperinum, em favor do hospedeiro e em detrimento do parasita. A contribuição de K aumentou a concentração de N da folhagem de J. flaccida. As análises vectoriais mostraram que a combinação do fósforo com a elevada dose de potássio levou a um aumento da biomassa de J. flaccida.

Abstract Juniperus flaccida Schltdl. is a very important forest species which is severely affected by Phoradendron juniperinum Engelm. at El Cardonal, Hidalgo, Mexico. The objective of this research was to evaluate the response, in terms of tree twig biomass and nutrient status of both the tree and its parasitic species, to fertilization with nitrogen (N), phosphorus (P), and potassium (K), in a natural forest of J. flaccida. The fertilizer rates and sources were 0,1000; 0, 300 and 0, 450, 900 g tree-1 of urea, phosphoric acid and potassium sulphate, respectively. The experimental design was a completely randomized factorial (2x2x3) with six replicates. Soil analysis showed low levels of N and P, and adequate levels of K in the site. Nitrogen or phosphorus alone did not significantly affect twig biomass, despite of being deficient nutrients in the study site. J. flaccida displayed higher concentrations of N, Mg, Cu, Mn, and B than P. juniperinum and the latter, showed higher concentrations of P, K, Ca, Fe, and Zn than its host species. Application of nitrogen significantly decreased the concentration of K in P. juniperinum and influenced the partition of foliar P between J. flaccida and P. juniperinum, in favor of the host tree and to the detriment of the parasitic species. Application of K increased foliar N in J. flaccida. Vector analysis showed that the combination of phosphorus with the highest dose of potassium led to an increase in twig biomass of J. flaccida.

Resumen Juniperus flaccida Schltdl. es una especie forestal muy importante que, en El Cardonal, Hidalgo, México es fuertemente atacada por Phoradendron juniperinum Engelm. El objetivo de esta investigación fue evaluar la respuesta de ramillas de J. fláccida en cuanto a su biomasa, su estado nutrimental y el de su planta parásita, con relación a las aplicaciones de nitrógeno (N), fósforo (P) y potasio (K), en un bosque natural de Juniperus flaccida. Las dosis y fuentes de fertilizantes fueron 0 y 1000; 0 y 300; y 0, 450 y 900 g árbol-1 de urea; ácido fosfórico y sulfato de potasio, respectivamente. El diseño experimental utilizado fue completamente al azar con arreglo factorial 2X2X3, con seis repeticiones. Los análisis de suelo mostraron bajos niveles de N y P, y suficientes de K en el sitio. Las aplicaciones individuales de N y P no tuvieron efectos significativos en biomasa, a pesar de ser deficientes en el área experimental. J. flaccida presentó mayores concentraciones foliares de N, Mg, Cu, Mn y B que P. juniperinum, y éste presentó mayores concentraciones de P, K, Ca, Fe y Zn que su hospedero. La aplicación de nitrógeno disminuyó significativamente la concentración de K en P. juniperinum e influyó en la partición de P foliar entre J. flaccida y P. juniperinum, en favor de la hospedera y en detrimento de la parásita. El aporte de K incrementó la concentración de N del follaje de J. flaccida. Los análisis de vectores mostraron que la combinación de fósforo con la dosis alta de potasio propició un incremento en biomasa de J. flaccida.

RESUMEN Los principales problemas de la producción de pepino, residen mayormente en la escasez de fertilizantes minerales, afectaciones climatológicas y limitado uso de los biofertilizantes, por lo cual, es importante buscar alternativas eficientes que aumenten la productividad, la racionalidad y la sustentabilidad. El objetivo de esta investigación fue evaluar la utilización individualizada y asociada de los biofertilizantes microorganismos eficientes y vermicompost lixiviado en el incremento agroproductivo del pepino. El trabajo fue desarrollado en la unidad productiva “El Estadio”, Sancti Spíritus, Cuba, entre enero a abril de 2015 y fue utilizado el cultivar Su Yi Sung de pepino. Los tratamientos aplicados fueron un control, inoculación al suelo y aplicaciones foliares de Microorganismos eficientes y vermicompost lixiviado, a 100 y 200mL L-1 y la inoculación al suelo, con Microorganismos eficientes, a 100mL L-1 y aplicaciones foliares con vermicompost lixiviado, a 100mL L-1. Las variables evaluadas fueron el número de hojas, de flores femeninas y de frutos por planta, longitud de frutos (cm), masa de los frutos (g) y el rendimiento (kg m-2). Los resultados mostraron que la aplicación individual y combinada de los biofertilizantes tuvieron un efecto bioestimulante en la producción de pepino y la aplicación de microorganismos eficientes a 100mL L-1 y la combinación con vermicompost lixiviado a 100mL L-1 constituyen una alternativa en la productividad del cultivo, especialmente, porque aumentaron el número de hojas, flores femeninas, frutos, masa y longitud de los frutos e incrementaron el rendimiento en 42% con relación al tratamiento control.

ABSTRACT The main problems of cucumber production reside fundamentally by the mineral fertilizer’s shortage, climatic affectation and limited use of biofertilizers, which is important to looking for efficient alternatives that increase productivity, rationality and sustainability. The objective of this research was to evaluate the effect of individualized and associated use of biofertilizers efficient microorganisms and lixiviate vermicompost on the agro-productive increase of cucumber. The work was developed in the productive unit "El Estadio", Sancti Spíritus, Cuba, between January to April 2015 and Su Yi Sung cultivar of cucumber was used. The treatments used were a control (no application), soil inoculation and foliar applications with efficient microorganisms and lixiviate vermicompost at 100 and 200mL L-1, and soil inoculation with efficient microorganisms at 100mL L-1 and foliar applications with lixiviate vermicompost at 100mL L-1. The following variables were observed: number of leaves, female flowers and fruits per plant, length of fruits (cm), mass of fruits (g) and yield (kg m-2). The results showed that the individual and combined application of biofertilizers had a biostimulants effect on cucumber production. The efficient microorganism’s application at 100mL L-1 and the combination with lixiviate vermicompost to 100mL L-1 constituting a sustainable alternative in the cucumber productivity, especially because they increased the number of leaves, female flowers, fruits, mass and length of fruits and increasing the yield by 42 % compared to control treatment.