Initial Development of Corn Seedlings after Seed Priming with Nanoscale Synthetic Zinc Oxide

Nanofertilizers are increasingly explored for sustainable micronutrient delivery in agriculture. Pre-treating seeds with nanofertilizers prior to planting (i.e., seed priming) reduces concerns about nanoparticle (NP) fertilizer non-target dispersion; however, priming formulations and concentrations must be carefully selected to avoid germination inhibition and toxicity. Here we investigate changes in corn seed germination and seedling development after seed priming with ZnO NPs, ZnO bulk and ZnCl2. To evaluate the effects sterile seeds were immersed in priming solutions of 0, 20, 40, 80, 160 mg L−1 Zn for the three Zn sources. Following an 8 h priming the seeds were evaluated for germination and vigor for 5 days on germination paper. Root and shoot lengths were measured as well as fresh and dry biomass. Compared to the control, the ZnO NP and ZnCl2 seed priming promoted beneficial effects. ZnO NP seed-priming exhibited a concentration dependent profile in improving seedling growth, with greatest benefit around 80 mg L−1, providing 17%, 25% and 12% higher values than control for germination, root length, and dry biomass production, respectively. In contrast, seeds primed with bulk ZnO did not differ from the control. These findings support NP-seed priming as an alternative to delivery of essential micronutrients, such as zinc, to corn seedlings

Foliar macronutrient contents and maize (Zea mays L.) production in response to gypsum application in an oxisol

The application of gypsum to the soil provides a favorable environment for the development of the root system, supplying the subsurface layers with elements such as calcium and sulfur and reduce the toxic aluminum activity. The objective of this study was to evaluate the influence of gypsum doses application on the maize (Zea mays L.) yield and the nutrients levels in the leaves. The study was conducted in the municipality of Terra Roxa - PR in an Oxisol using experimental design of randomized blocks with four replications. The treatment were composed of different doses of gypsum (0, 3.0, 6.0 and 9.0 t ha-1) applied after sowing corn. When the plants were in the R1 stage leaves were collected and analyzed the levels of N, P, K, Ca, Mg and S. After physiological maturity, the harvest of each plot was carried out, the moisture correction and determination of productivity. The N, P and S increased with foliar applications of increasing gypsum doses. On the other hand, foliar K, Ca and Mg not significantly altered by the gypsum application. The corn yield increases with the application of gypsum to the dose of 6.22 t ha-1, providing an increase of 17.8%.The application of agricultural gypsum to the soil provides a favorable environment for the root development. It supplies the subsurface layers with elements such as calcium and sulfur and reduces the toxic aluminum activity. The objective of this study was to evaluate the influence of gypsum doses application on the maize (Zea mays L.) yield and the nutrients content of the leaves. The study was conducted in Terra Roxa city, Paraná State, Brasil, in an Oxisol. The experimental design was the randomized blocks with four replicates. The treatment were composed of four doses of gypsum (0; 3.0; 6.0 and 9.0 t ha-1) applied after the corn sowing. At the R1 phenological stage, the leaves were collected and the N, P, K, Ca, Mg and S levels were analyzed. After the physiological maturity, the plots were harvested for the productivity determination. The grain moisture was adjusted to 13%. The nitrogen, P and S foliar contents increased according to the gypsum doses increasing. On the other hand, K, Ca and Mg foliar content did not respond significantly to the gypsum application. The corn yield increased with the application of gypsum to the dose of 6.22 t ha-1, providing an increase of 17.8% in relation to the control

Adubação nitrogenada e pulverização foliar de Azospirillum brasilense em trigo: efeitos na nutrição mineral e produtividade

The use of Azospirillum brasilense has the potential to improve plant nitrogen (N) use efficiency, while a better understanding of alternative management practices with inoculation is necessary. The aim was to examine the effects of the leaf application of A. brasilense in association with nitrogen fertilization on the wheat crop. The experiment was conducted in Lidianópolis, Paraná, Brazil, in a completely randomized block design with four replications. The treatments included four doses of A. brasilense for leaf application (0, 200, 400, and 600 ml ha-1) and four doses of N (0, 40, 80, and 120 kg N ha-1). The nutritional content, yield components, quality, and yield of the wheat crop were evaluated. There was no interaction among the factors, nor did the treatments have an isolated effect on spike length, the number of spikelets per spike, spikes per m2, thousand grain weight, and test weight. However, doses of A. brasilense increased calcium and magnesium absorption at 283 and 380 ml ha-1, respectively. Similarly, nitrogen application increased the content of calcium, magnesium, and copper in the leaf at 61, 47, and 49 kg N ha-1, respectively. Nitrogen also increased the number of grains per spike and yield at 56 and 54 kg N ha-1, respectively. Yield correlated with the number of grains per spike and the manganese and copper content in the leaf. The results demonstrate that the inoculation of leaves with A. brasilense favored a higher absorption of divalent cationic macronutrients and that N was fundamental to increasing the yield, with the best responses observed between 47 and 61 kg ha-1.O uso de Azospirillum brasilense apresenta potencial em melhorar a eficiência de uso do nitrogênio (N), sendo necessário melhor compreensão de formas alternativas de inoculação, visto que o tratamento químico de sementes pode comprometer a eficiência das bactérias. O objetivo foi avaliar os efeitos do A. brasilense aplicado via foliar associado a adubação nitrogenada na cultura do trigo. O experimento foi implantado em Lidianópolis, no estado do Paraná, Brasil, em blocos completos com tratamentos ao acaso e quatro repetições, sendo os tratamentos: quatro doses de A. brasilense via foliar (0, 200, 400 e 600 ml ha-1) e quatro doses de N (0, 40, 80 e 120 kg N ha-1). Foram avaliados os teores nutricionais, componentes de rendimento, qualidade e produtividade. Não houve interação entre os fatores, tampouco efeito isolado dos tratamentos para comprimento da espiga, número de espiguetas por espiga, espigas por m², massa de mil grãos e peso de hectolitro. Todavia as doses de A. brasilense, aumentaram a absorção de Ca e Mg até a dose de 283 e 380 ml ha-1, respectivamente. De modo similar, o N aplicado aumentou os teores foliares de cálcio, magnésio, além de cobre até a dose de 61, 47 e 49 kg ha-1 de N, respectivamente. O N também incrementou o número de grãos por espiga e a produtividade até a dose 56 e 54 kg N ha-1, respectivamente, porém a eficiência de uso de N diminuiu com o aumento da dose. A produtividade se correlacionou com número de grãos por espiga e teores foliares de manganês e cobre. Os resultados demonstram que a inoculação com A. brasilense foliar foi favorável a maior absorção de macronutrientes catiônicos divalentes, e o N fundamental para aumento da produtividade, sendo as melhores respostas obtidas entre as doses de 47 a 61 kg ha-1

Corn response to phosphogypsum, base saturation and lime application method

The lime (L) and phosphogypsum (G) promote changes in the chemical attributes of the soil that can alter the development of corn. The objective was to evaluate morphological and yield components of corn after liming and G and to correlate them with yield. The treatments consisted of a 2 x 4 + 3 factorial, with two methods of application of L: surface (SL) and incorporated (IL) to obtain different levels of base saturation (BS): 44, 60, 70 and 90%. Three additional treatments were evaluated involving the use of L and G applied on the surface, being: BS 60% + 3.71 Mg ha-1 of G (60G50); BS 70% + 3.71 Mg ha-1 of G (70G50) and BS 70% + 7.42 Mg ha-1 of G (70G100). Plant height (PH), ear insertion height (EIH) and stem diameter (SD) were not influenced by the treatments. The SL increased the length of the ear (LE), number of grains per row (NGR) and mass of a thousand grains (TMG) up to BS of 72, 80 and 72%, respectively. Thus, there were no advantages of higher base saturation (BS 90%). The combination of L and G promoted improvements in ear diameter (ED), NGF, LE, TMG. The yield in IL was 445 kg ha-1 higher than SL, however when combining G and L the production increased 6 to 12% in relation to BS 44% SL. BS% levels in IL did not influence any response variable. Grain yield was positively correlated to ED, TMG, LE and PH

Nutrient Removal by Grain in Modern Soybean Varieties

Knowing the nutrient removal by soybean grain harvest in different varieties, locations, and over time is essential to correctly adjust agronomic recommendations, update farmers’ practices, and increase nutrient use efficiency. A field-based research trial was carried out to assess macronutrients [nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), and sulfur (S)] removed in grain by modern soybean varieties from southern Brazil introduced between 2007 and 2016. We examined changes between our set of modern varieties and a dataset of historical values encompassing a wide range of varieties introduced before 2007. Moreover, we undertook a synthesis analysis using scientific literature published after 2007 to investigate nutrient removal by grain among modern Brazilian soybeans and a dataset that included field trials from Argentina, United States, and India. There were no yield gains across the years for modern soybean varieties introduced among 2007 and 2016 in Brazil, although the grain N and Mg concentrations decreased. Modern Brazilian soybeans increased nutrient removal compared with that by soybeans historically planted in Brazil, with 11.1, 26.9, 45.0, and 31.6% more N, P, K, and Mg removed, respectively. Our results indicated that soybean growing in Brazil removed 4.3% less N relative to the values reported in the literature dataset, whereas K removal was 21.4% greater. A significant difference was also recorded for high-yield soybean varieties, and Brazilian varieties removed 11.8% less N and 8.6% more K than varieties in the literature dataset. No differences were found among locations for P removal, averaging 4.9 kg Mg–1 grain. In conclusion, this study indicates that the amounts of nutrients removed by modern soybean varieties were greater relative to the historical values recorded in Brazil, excluding Ca and S. Nonetheless, in the middle to long term (10 years), a significant impact of plant breeding on grain nutrient concentration was recorded only for N and Mg. The difference in nutrient removal patterns between Brazil and other countries indicates an integrated effect of management, genotype, and environment on nutrient removal. These findings provide guidance for optimal nutrient management and specific information for plant breeding programs to understand nutrient variability

Thermal Transformation and Characterization of Synthetic Al-Substituted Maghemites (γ-Fe 2-x Al x O 3 )

ABSTRACT: Burning is a common practice in tropical areas and related changes in mineralogy might affect the chemical and physical behavior of soils. Maghemite is a common iron oxide in soils formed from basic rocks in tropical regions. This mineral and hematite are the main pigments in these soils and exhibit high magnetization stemming from the precursor magnetite formed during the weathering process of primary minerals. The objective of the present study was to analyze changes in color, magnetic suceptibility values, Fourier transform infrared spectroscopy (FTIR) spectra, and available Fe and Al contents extracted with 1 mol L -1 KCl during the process of thermal transformation of synthetic Al-maghemites into Al-hematites. Synthetic substituted maghemites with different degrees of Al-substitution (0.0, 1.0, 2.0, 2.9, 3.8, 5.6, 6.7, 10.0, 12.0, and 17.1 mol% Al) were subjected to a temperature of 500 ± 10 °C for 0, 5, 10, 16, 64, 128, 192, 360, 720, 2160, 3600, 5040 and 6480 min. The color of the samples was analyzed by a Munsell system in a colorimeter. Mass-specific magnetic susceptibility (χ LF ) was measured at low-frequency. Available Fe and Al contents were estimated by a 1 mol L -1 KCl solution. Fourier transform infrared spectroscopy (FTIR) spectra were obtained through use of a Bruker Vertex 70X FTIR spectrophotometer at a spectral resolution of 4 cm -1 . Contents of Fe and Al extracted by 1 mol L -1 KCl in Al-hematites were not detected. All samples analyzed exhibited YR hue. Hue proportion decreased with increased heating time, and color changed from brown to red. The increase in isomorphic substitution (IS) led to increased hue values from maghemite to hematite, and the latter then became yellower. The χ LF values decreased with an increase in heating time, indicating transformation from a ferrimagnetic phase (maghemite) to an antiferrimagnetic phase (hematite). With increasing IS, the maghemite χ LF values decreased. Bands of the initial members (time 0) in the FTIR spectra were indexed as maghemites. The end members after completion of the heat treatment were identified as hematites. The IS of Fe by Al in maghemite influenced the thermal transformation to hematite, as well as the color and χ LF of the minerals. The χ LF proved to be very efficient in detecting maghemites remaining after thermal processing. Fe and/or Al were not ejected from the hematite crystalline structure after heat treatment

Thermal Transformation and Characterization of Synthetic Al-Substituted Maghemites (γ-Fe2-xAlxO3)

ABSTRACT Burning is a common practice in tropical areas and related changes in mineralogy might affect the chemical and physical behavior of soils. Maghemite is a common iron oxide in soils formed from basic rocks in tropical regions. This mineral and hematite are the main pigments in these soils and exhibit high magnetization stemming from the precursor magnetite formed during the weathering process of primary minerals. The objective of the present study was to analyze changes in color, magnetic suceptibility values, Fourier transform infrared spectroscopy (FTIR) spectra, and available Fe and Al contents extracted with 1 mol L-1 KCl during the process of thermal transformation of synthetic Al-maghemites into Al-hematites. Synthetic substituted maghemites with different degrees of Al-substitution (0.0, 1.0, 2.0, 2.9, 3.8, 5.6, 6.7, 10.0, 12.0, and 17.1 mol% Al) were subjected to a temperature of 500 ± 10 °C for 0, 5, 10, 16, 64, 128, 192, 360, 720, 2160, 3600, 5040 and 6480 min. The color of the samples was analyzed by a Munsell system in a colorimeter. Mass-specific magnetic susceptibility (χLF) was measured at low-frequency. Available Fe and Al contents were estimated by a 1 mol L-1 KCl solution. Fourier transform infrared spectroscopy (FTIR) spectra were obtained through use of a Bruker Vertex 70X FTIR spectrophotometer at a spectral resolution of 4 cm-1. Contents of Fe and Al extracted by 1 mol L-1 KCl in Al-hematites were not detected. All samples analyzed exhibited YR hue. Hue proportion decreased with increased heating time, and color changed from brown to red. The increase in isomorphic substitution (IS) led to increased hue values from maghemite to hematite, and the latter then became yellower. The χLF values decreased with an increase in heating time, indicating transformation from a ferrimagnetic phase (maghemite) to an antiferrimagnetic phase (hematite). With increasing IS, the maghemite χLF values decreased. Bands of the initial members (time 0) in the FTIR spectra were indexed as maghemites. The end members after completion of the heat treatment were identified as hematites. The IS of Fe by Al in maghemite influenced the thermal transformation to hematite, as well as the color and χLF of the minerals. The χLF proved to be very efficient in detecting maghemites remaining after thermal processing. Fe and/or Al were not ejected from the hematite crystalline structure after heat treatment

Alterações químicas de um Latossolo Vermelho distroférrico após aplicação de efluente alcalino da indústria farmacêutica

Effluents from different industrial supply conglomerates are often discarded in the environment without proper treatment. The concern for an economically viable industrial production line, which is both environmentally sound and socially acceptable, is increasing. Some of these effluents are alkaline in nature and may be used as an alternative to chemical conditioners for acidic soils in agricultural systems. This research aimed to evaluate changes in the chemical attributes of a Dystroferric Red Latosol (Oxisol) after application of an effluent from a pharmaceutical industry. The experiment was conducted in a greenhouse using PVC tubes of 1-m length and a 0.2-m diameter filled with soil and different doses of the effluent. After 3 days, 100 mm of water was applied to each treatment. The PVC tubes were incubated for 30 days; thereafter, the tubes disassembled, and soil chemical analyses were made at different soil depths: 0-0.2, 0.2-0.4, 0.4-0.6, 0.6-0.8, and 0.8-1.0 m. The effluent applications significantly altered the soil elements in the 0-0.2 m layer, increasing the concentrations of K+, P, Mn2+, Na+, Cu2+, H+, Ca2+, Al3+ and the soil pH. In the subsurface layers, the concentration of the elements Zn2+, Cu2+, K+, and Na+ also changed significantly. In general, the application of pharmaceutical industry residue improved soil chemical attributes.Os efluentes das diversas cadeias produtivas industriais são muitas vezes descartados no ambiente sem tratamento adequado. A preocupação por uma linha de produção industrial economicamente viável, ambientalmente correta e socialmente aceita é cada vez mais preconizada. Alguns desses efluentes apresentam caráter alcalino, e podem ser utilizados como condicionadores químicos de solos ácidos, em sistemas agrícolas. Objetivou-se com a realização do presente trabalho, avaliar alterações químicas de um Latossolo Vermelho distroférrico, após aplicação de efluente da indústria farmacêutica. O experimento foi realizado em casa de vegetação e conduzido em tubos de PVC de 1 m de comprimento e 0,2 m de diâmetro. Nos tubos, preenchidos com solo, foram aplicadas diferentes doses do efluente. Após 3 dias, 100 mm de água foram aplicadas sobre cada tratamento. As colunas foram incubadas por 30 dias, posteriormente desmontadas e feitas análises químicas nas diferentes profundidades: 0-0,2; 0,2-0,4; 0,4-0,6; 0,6-0,8 e 0,8-1,0 m. As aplicações do efluente fizeram com que alguns elementos do solo aumentassem significativamente sua concentração, principalmente na camada de 0-0,2 m entre eles estão o K+, P, Mn2+, Na+, Cu2+, H+, Ca2+ e Al3+, além do pH. Nas camadas subsuperficiais os elementos Zn2+, K+, Cu2+ e Na+ sofreram alterações significativas. A aplicação do resíduo da indústria farmacêutica melhorou as características químicas do solo