The Effect of N Fertilization on Wheat under Inoculation with Azospirillum brasilense

The biological nitrogen fixation (BNF) process in wheat (Triticum aestivum L.) occurs by diazotrophic bacteria, particularly Azospirillum brasilense. However, researches are lacking on BNF efficiency to define how much mineral nitrogen (N) can be applied to achieve more sustainable high yields, and if urea with the urease enzyme inhibitor is less harmful, benefiting BNF in grasses (cereals). Therefore, the objective was to evaluate the effect of N sources (urea and Super N, urea with urease enzyme inhibitor N‐(n‐butyl thiophosphoric triamide) (NBPT) and N rates (0, 50, 100, 150, and 200 kg ha−1) applied in topdressing associated with inoculation with A. brasilense, regarding the leaf N concentration, leaf chlorophyll index (LCI), accumulation of N in the straw and grains, the nitrogen utilization efficiency (NUE), recovery of the applied nitrogen (RAN), physiological efficiency (FE), agronomic efficiency (AE), and wheat grain yield in the Brazilian Cerrado (tropical savanna) region. The N sources provide similar N accumulations in straw and grains, and wheat grain yield. Inoculation with A. brasilense afforded higher N grain concentration (increase in protein content more sustainably) by applying less N fertilizer in topdressing. Inoculation with A. brasilense increased the AE, RAN, and NUE

Inoculation with Bradyrhizobium sp. and Azospirillum brasilense Associated with Application of Cobalt and Molybdenum on Nutrition and Soybean Yield

Considering the main current limitations and potential of biological fixation of N2 (BNF) in soybean crop and benefits attributed to various crops by inoculation with Azospirillum brasilense (diazotrophic bacteria with free life), with emphasis on larger development of the root system and consequently greater absorption of water and nutrients, we can infer that co‐inoculation with both microorganisms of Bradyrhizobium sp. and A. brasilense can improve the crop performance in an approach that meets the current demands of agricultural, economic, and environmental sustainability. Thus, important researches are needed to evaluate the nutritional status, production components, and the soybean yield affected by cobalt and molybdenum application mode and co‐inoculating seeds with bradyrhizobia and A. brasilense. We found that seed inoculated with A. brasilense and application of cobalt and molybdenum provided higher N concentration in leaf and mass of 100 grains, with a positive impact on the grain yield of soybean, with an increase of 1007 kg ha‐1 of grain, equivalent to 18.4% more than the control (only inoculated with rhizobia). This research demonstrated that co‐inoculation with Bradyrhizobium sp. and A. brasilense associated with the application of cobalt and molybdenum is beneficial for nutrition and soybean yields

Inoculation with Azospirillum brasilense Improves Nutrition and Increases Wheat Yield in Association with Nitrogen Fertilization

The management of nitrogen fertilization is performed in order to ensure adequate productivity, and depending on the N dynamics in the soil, large amount of N is added to the soil, raising production cost for the farmers. Considering the benefits attributed by seed inoculation with Azospirillum brasilense (diazotrophic bacteria), with emphasis on biological nitrogen fixation (BNF), greater development of the root system, and, consequently, greater absorption of water and nutrients, it infers that inoculation can improve crop performance allowing greater efficiency of nitrogen fertilization. Thus, the research that evaluates nutritional status and wheat yield, in terms of nitrogen rates in association with inoculation with A. brasilense is important. We found that increment of N rates in association with A. brasilense inoculation increases the wheat yield up to 139 kg ha−1 N, whereas without this inoculation linear increase occurred with lower maximum yield of wheat. That is, the inoculation afforded higher grain yield applying less nitrogen fertilizer in topdressing. This research demonstrated that inoculation with A. brasilense associated with nitrogen fertilization in topdressing is beneficial to nutrition and wheat yield. Therefore, inoculation is a low-cost technique, easy to apply and use, and nonpolluting, which fall within the desired sustainable context in actuality

GLIFOSATO E MANGANÊS NA CONCENTRAÇÃO DE NUTRIENTES FOLIAR E CARACTERÍSTICAS AGRONÔMICAS DA SOJA

Objetivou-se estudar os efeitos da aplicação de glifosato e manganês (Mn) em estádios de desenvolvimento na nutrição e características agronômicas da cultura da soja, no município de Selvíria-MS, Brasil, na safra 2012/13, utilizando-se a variedade de soja BRS Valiosa RR em um Latossolo Vermelho Distrófico, de textura argilosa. O delineamento experimental foi em blocos casualizados com quatro repetições, distribuídos em esquema fatorial 6x2, sendo: seis doses de aplicação de glifosato (0 g i.a. ha-1, aplicação de 720 g i.a. ha-1 no estádio V3, 1440 g i.a. ha-1 em V3, 720+720 g i.a. ha-1 em V3 e V7, 1440 g i.a. ha-1 em V7, e aplicação de 720+1440 g i.a. ha-1 em V3 e V7; com ou sem aplicação de Mn (0 g ha-1 e 350 g ha-1), no estádio V5. A aplicação foliar de Mn e de glifosato não influenciou as concentrações dos macro e micronutrientes foliar da cultura da soja. O glifosato nas doses de 720+1440 g i.a. ha-1, aplicado nos estádios V3 e V7, associado a adubação foliar com 350 g ha-1 de Mn no estádio V5, reduz a altura de inserção da primeira vagem, porém aumenta o número de grão por vagem. A produtividade de grãos de soja foi reduzida com a aplicação de glifosato na dose de 720+1440 g i.a. ha-1, nos estádios V3 e V7, independentemente da aplicação foliar com Mn

EFFECT OF INSTANTANEOUS LIGHT INTENSITY AFTER MAGNESIUM SUPPRESSION IN TOMATO AND BELL PEPPER CULTIVATION

Plants dynamically respond to varying light intensities, which may further interact with their nutrient status to affect gas exchange parameters. This study investigated the combined effect of instantaneous light intensity and magnesium suppression on tomato and bell pepper cultivation. Two independent experiments were conducted in September 2022 using the tomato variety Mariana (Sakata®) and bell pepper variety Magali R (Sakata®) at the Faculty of Agricultural and Technological Sciences, Dracena, São Paulo, Brazil. A completely randomized 2x5 factorial design was employed, with the first factor being the presence/absence of magnesium in the nutrient solution and the second factor being four light intensities: 0 (control), 600, 1200, and 1800 μmol m⁻² s⁻¹ photosynthetically active radiation (PAR) applied instantaneously using an IRGA device. Magnesium deficiency was confirmed to be a limiting factor for gas exchange responses in both tomato and pepper crops. Notably, the light intensity of 1200 μmol m⁻² s⁻¹ PAR elicited the most optimal gas exchange performance in both plant species

Thidiazuron increases upland rice yield

The use of plant growth regulators in rice can provide reductions in plant height and decrease plant lodging. This study aimed at verifying the influence of the thidiazuron plant regulator on upland rice in the Brazilian Savannah region. The BRS Esmeralda and IAC 202 cultivars were used, as well as a randomized blocks design, in a 4 x 3 factorial arrangement for each cultivar, consisting of thidiazuron doses (0 g ha-1, 0.3 g ha-1, 0.6 g ha-1 and 0.9 g ha-1) and three application times (tillering, floral differentiation and booting), with four replications. The number of spikelets per panicle and spikelet fertility of the BRS Esmeralda cultivar were higher when using the thidiazuron dose of 0.9 g ha-1 in the tillering stage. The weight of 100 grains of the BRS Esmeralda cultivar fitted a quadratic equation, while the IAC 202 fitted a linear equation, with the best time of application taking place during the tillering stage. For hectoliter weight, the results for the BRS Esmeralda also fitted a quadratic equation, while for the IAC 202 a significant difference was observed only among times, being the booting stage the best application time. Grain yield fitted a positive linear equation for both the BRS Esmeralda and IAC 202 cultivars, with gains of 23.5 % and 6.5 %, respectively, when compared to the control. Thidiazuron positively influences grain yield for upland rice

ACÚMULO DE MATÉRIA SECA E NUTRIENTES NO CAPIM-MOMBAÇA EM FUNÇÃO DO MANEJO DA ADUBAÇÃO NITROGENADA

O nitrogênio é um elemento de extrema importância na cultura de forrageiras, sendo o nutriente que mais influencia na produtividade e na qualidade das pastagens. Objetivou-se estudar a condução de uma pastagem com alto potencial produtivo utilizando fontes e doses de nitrogênio. As fontes de N foram nitrato de amônio (N.A.) e ureia aplicadas nas doses de N: 0, 50, 100, 150 e 200 kg ha-1 por corte, na espécie forrageira Panicum maximum cv. Mombaça, avaliando o acúmulo de nitrogênio (N), fósforo (P) e potássio (K) e a taxa de acúmulo de matéria seca (MS). As fontes de N não influenciaram o acúmulo de N, P e K e taxa de acúmulo de MS. As doses influenciaram positivamente no acúmulo de N, K e a taxa de acúmulo de MS, ocorrendo incremento com o aumento das doses de N. Como as fontes de N não influenciaram os atributos analisados recomenda-se o uso da ureia por ser o fertilizante de maior concentração de N e de menor relação custo por unidade de nutriente, na dose de 100 kg ha-1, propiciando maior acúmulo de nutrientes e ganho na MS, além da manutenção do capim-mombaça

Mesoscopic Architectures Made of Electrically Charged Binary Colloidal Nanosheets in Aqueous System

Inorganic layered materials can be converted to colloidal liquid crystals through exfoliation into inorganic nanosheets, and binary nanosheet colloids exhibit rich phase behavior characterized by multiphase coexistence. In particular, niobate–clay binary nanosheet colloids are characterized by phase separation at a mesoscopic (∼several tens of micrometers) scale whereas they are apparently homogeneous at a macroscopic scale. Although the mesoscopic structure of the niobate–clay binary colloid is advantageous to realize unusual photochemical functions, the structure itself has not been clearly demonstrated in real space. The present study investigated the structure of niobate–clay binary nanosheet colloids in detail. Four clay nanosheets (hectorite, saponite, fluorohectorite, and tetrasilisic mica) with different lateral sizes were compared. Small-angle X-ray scattering (SAXS) indicated lamellar ordering of niobate nanosheets in the binary colloid. The basal spacing of the lamellar phase was reduced by increasing the concentration of clay nanosheets, indicating the compression of the liquid crystalline niobate phase by the isotropic clay phase. Scattering and fluorescence microscope observations using confocal laser scanning microscopy (CLSM) demonstrated the phase separation of niobate and clay nanosheets in real space. Niobate nanosheets assembled into domains of several tens of micrometers whereas clay nanosheets were located in voids between the niobate domains. The results clearly confirmed the spatial separation of two nanosheets and the phase separation at a mesoscopic scale. Distribution of clay nanosheets is dependent on the employed clay nanosheets; the nanosheets with large lateral length are more localized or assembled. This is in harmony with larger basal spacings of niobate lamellar phase for large clay particles. Although three-dimensional compression of the niobate phase by the coexisting clay phase was observed at low clay concentrations, the basal spacing of niobate phase was almost constant irrespective of niobate concentrations at high clay concentrations, which was ascribed to competition of compression by clay phase and restoring of the niobate phase

Teor de água nos grãos, em ocasião de colheita nas perdas ocorridas no milho

A utilização de métodos de fácil aplicação e com resultados rápidos são importantes para que os produtores de milho possam decidir o momento correto para realização da colheita com redução das perdas com a secagem natural. Objetivou-se estudar o teor de água ideal dos grãos na colheita da cultura do milho, a produtividade e os componentes produtivos, bem como as perdas com a secagem natural em campo. O delineamento experimental foi o de blocos ao acaso com quatro repetições e os tratamentos consistiram na colheita nos seguintes teores de água em base úmida (b.u.) dos grãos: 28,9 (ponto de maturidade fisiológica plena), 23,5; 21,9; 18,9; 16,1; e 13,8%, avaliando-se a umidade do ápice, meio e base da espiga, altura de plantas, altura de inserção de espigas, diâmetro do colmo, número de fileiras e grãos por fileiras, número de grãos por espiga, prolificidade, massa de 100 grãos e produtividade de grãos. Os componentes produtivos relacionados à planta e aos grãos não foram influenciados pela umidade de grãos na ocasião da colheita. A umidade da ápice, meio e base da espiga, massa de 100 grãos e a produtividade de grãos de milho foram influenciados pela umidade de grãos na ocasião da colheita