Efficiency of soluble and insoluble sources of manganese for soybean nutrition in the Brazilian Cerrado

O objetivo deste trabalho foi avaliar a eficiência de fontes e doses de magnésio solúvel (MnSO4.H2O) e insolúvel (MnCO3) nos processos de absorção, transporte e redistribuição deste nutriente na soja (Glycine max), bem como na produtividade da cultura, em solo de Cerrado. O delineamento experimental foi em blocos ao acaso, em arranjo fatorial 4×2 – quatro doses (150, 250, 350 e 450 g ha-1) × duas fontes (MnSO4.H2O e MnCO3) de Mn –, com quatro repetições. Nas safras de 2015/2016 e 2016/2017, realizaram-se adubações foliares no terceiro trifólio e avaliaram-se os conteúdos de Mn e a produtividade da soja. Em ambas as safras, a fertilização foliar com Mn aumentou os teores do nutriente nas folhas, nos caules e nos grãos, mas não afetou o rendimento de grãos e a produção de matéria seca. Os teores máximos de Mn nas folhas foram obtidos com doses entre 150 e 450 g ha-1. A aplicação de MnSO4.H2O aumentou a absorção, o transporte e a redistribuição de Mn na planta, com desempenho superior ao de MnCO3. A fertilização foliar com MnSO4.H2O em soja, em solo de Cerrado, aumenta os teores de Mn nas folhas, mas não a produtividade e a produção de matéria seca.The objective of this work was to evaluate the efficiency of sources and rates of soluble (MnSO4.H2O) and insoluble (MnCO3) manganese on the processes of uptake, transport, and redistribution of this nutrient in soybean, as well as on crop yield, in Cerrado soil. The experimental design was randomized complete blocks in a 4×2 factorial arrangement – four rates (150, 250, 350, and 450 g ha-1) × two sources (MnSO4.H2O and MnCO3) of Mn –, with four replicates. In the 2015/2016 and 2016/2017 crop seasons, foliar fertilizations were carried out on the third trifoliate leaflet, and Mn content and soybean yield were evaluated. In both crop seasons, Mn foliar fertilization increased the contents of the nutrient in leaves, stems, and grains, but did not affect grain yield and dry matter production. The maximum Mn contents in leaves were obtained with rates between 150 and 450 g ha-1. The fertilization with MnSO4.H2O increased Mn uptake, transport, and redistribution in the plant, with a performance superior to that of MnCO3. Foliar fertilization with MnSO4.H2O in soybean, in a Cerrado soil, increases Mn contents in the leaves but not yield and dry matter production

SOIL ATTRIBUTES IN CONVENTIONAL TILLAGE OF Coffea arabica L.: A CASE STUDY

Coffee production presents great economic and social importance. To increases coffee production and decreases the environmental impacts of its activity, it is necessary to know the soil attributes and their impacts on plant development. Therefore, due to the importance of the soil physical and chemical attributes, as well as the significance of coffee to Brazil, the objective of this study was to evaluate the physical and chemical attributes of an Oxisol planted with coffee conducted under conventional tillage system. For the purposes of analysis and interpretation of the data, the experiment was performed and interpreted in a completely randomized design, with the factorial 3 x 2, referring to three locations in the area of the coffee plantation (planting line, canopy projection, between planting lines) and two soil layers (0 - 0.2 m and 0.2 - 0.4 m), with four replications. It is concluded that no distinctions for soil porosity and total porosity was observed among soil locations, and that ‘planting line’ position showed superior concentrations of total organic carbon and mean geometric diameter of the soil aggregates.Coffee production presents great economic and social importance. To increases coffee production and decreases the environmental impacts of its activity, it is necessary to know the soil attributes and their impacts on plant development. Therefore, due to the importance of the soil physical and chemical attributes, as well as the significance of coffee to Brazil, the objective of this study was to evaluate the physical and chemical attributes of an Oxisol planted with coffee conducted under conventional tillage system. For the purposes of analysis and interpretation of the data, the experiment was performed and interpreted in a completely randomized design, with the factorial 3 x 2, referring to three locations in the area of the coffee plantation (planting line, canopy projection, between planting lines) and two soil layers (0 - 0.2 m and 0.2 - 0.4 m), with four replications. It is concluded that no distinctions for soil porosity and total porosity was observed among soil locations, and that ‘planting line’ position showed superior concentrations of total organic carbon and mean geometric diameter of the soil aggregates

Recalcitrant carbon and nitrogen in agriculture soils with residue accumulation and fertilization under tropical conditions

Soil organic matter has a strong relation to total organic carbon, and about 85% of organic carbon consists of humic substances (HS), classified as humin (HU), humic (HA) and fulvic acids (FA), and denominated as recalcitrant carbon in soil. HS are formed by complex, heterogeneous and polydisperse molecules, which have significant influence on the soil physical and chemical characteristics. The study evaluates the hypothesis that agricultural soils treated with organic residues may present higher carbon stocks as presented in forest soils.  The aim of this study was to evaluate alterations in recalcitrant carbon and nitrogen stocks in Oxisol (Forest - FL, unfertilized Brachiaria - UB, and fertilized Brachiaria - FB) and Cambisol (Forest - FC, Coastcross - CC, sugarcane - CA, and silage corn - SM) at surface (0.0 - 0.1) and subsurface (0.1 - 0.2 m), in the Zona da Mata in Minas Gerais state, Brazil. Result shows that fertilization, low soil disturbance and residual removal promoted increase of C and N content in HS, being close to native forests. Both, carbon and nitrogen recalcitrant, presented reduction with soil depth. HU ranged from 10.5 to 16.7 g kg-1 and presented the highest concentration compared to FA and HA. In Oxisol, FL and FB presented the highest SH concentration and demonstrate the positive effect of fertilization on carbon stocks improving soil quality in well-managed and productive areas. While, In Cambisol, FC and CC presented higher carbon and nitrogen in HS, mainly for HU and HA fractions, and SM showed the lowest concentrations in all fractions. Our results suggest that soil managements with lower soil disturbance and residual removal promotes increasing of carbon and nitrogen in recalcitrant fraction, with concentration close to native forests. Pasture should be fertilized to improve recalcitrant carbon and nitrogen stocks, avoiding process of degradation in tropical soil. It is an important outcome due to high levels of degraded areas in Brazil caused by inadequate use of soil mainly with pasture

Organomineral as a substitute for mineral fertilization in potato cultivation

Potato (Solanum tuberosum, L.) is one of the most responsive crops to fertilizer application, which drives theneed to rationalize and make the most of nutritional resources in efficient and sustainable management. Basedon the hypothesis that the organomineral is a great alternative to increase potato productivity (Ágata andAtlantic cultivars) and that it can be indicated as a substitute for mineral fertilizers, this study aims to evaluatethe effect of organomineral doses applied in the planting furrow on potato productivity to identify the bestlevel of mineral fertilizer replacement. A study was conducted in the city of Cristalina (state of Goiás, Brazil),evaluating the replacement of 40, 60, 80, and 100% of mineral fertilizer (standard) provided via organomineralfertilizer in two widely cultivated varieties. The total productivity and the productivity in classes were monitored,as well as the nutrient contents in the leaves. The results showed that the organomineral is a great alternative toincrease potato productivity and can be indicated as a substitute for mineral fertilizers. For the cultivar Ágata,an organomineral dose of 80% is recommended concerning mineral fertilization. On the other hand, for theAtlantic cultivar, the same dose of mineral fertilizer is recommended. In both cultivars, there was an increase intuber size with organomineral fertilization, which indicates greater efficiency in tuber productivity.Potato (Solanum tuberosum, L.) is one of the most responsive crops to fertilizer application, which drives theneed to rationalize and make the most of nutritional resources in efficient and sustainable management. Basedon the hypothesis that the organomineral is a great alternative to increase potato productivity (Ágata andAtlantic cultivars) and that it can be indicated as a substitute for mineral fertilizers, this study aims to evaluatethe effect of organomineral doses applied in the planting furrow on potato productivity to identify the bestlevel of mineral fertilizer replacement. A study was conducted in the city of Cristalina (state of Goiás, Brazil),evaluating the replacement of 40, 60, 80, and 100% of mineral fertilizer (standard) provided via organomineralfertilizer in two widely cultivated varieties. The total productivity and the productivity in classes were monitored,as well as the nutrient contents in the leaves. The results showed that the organomineral is a great alternative toincrease potato productivity and can be indicated as a substitute for mineral fertilizers. For the cultivar Ágata,an organomineral dose of 80% is recommended concerning mineral fertilization. On the other hand, for theAtlantic cultivar, the same dose of mineral fertilizer is recommended. In both cultivars, there was an increase intuber size with organomineral fertilization, which indicates greater efficiency in tuber productivity

Optimal plant density and nitrogen rates for improving off-season corn yields in Brazil

Integrating plant density and nitrogen (N) management is a strategy for improving corn yields, especially for off-season corn production in the tropics. This study tested the hypothesis that increasing plant densities and N rates promotes yield gains for off-season corn production in high-yielding environments. The aim of the study was to investigate the yield performances of two hybrid versions (DKB PRO and DKB PRO3) submitted to three plant densities (55,000; 65,000 and 75,000 plants ha−1) and four N rates (control, 60, 120 and 180 kg ha−1 N). Field trials were undertaken at Uberlândia-MG (site1 and 2) and Pedro Afonso-TO (site 3), Brazil from which data on corn yield parameters were collected and analyzed. Multivariate analysis separated the three trial areas into two groups, presenting high (sites 1 and 2) and low yields (site 3), which were related to weather conditions. There was no influence of a hybrid version or plant densities on crop yields at site 1 or 2. In contrast, there was a positive response to increasing plant densities and the use of DKB PRO3 at site 3. A significant response to N was observed at sites 2 and 3, following a plateau model. Our results suggest that N application rates and plant densities do have the potential to increase off-season corn yields in low yielding environments

Productivity and mortality, of Fusarium oxysporum f. sp. passiflorae in passionfruit vines brs rubi do cerrado, grafted onto different rootstocks

The use of scions grafted onto passionfruit vines has become an alternative to their cultivation in areas with a history of fusariosis. However, the combinations between the graft and rootstock can influence on the productivity and longevity of the passionfruit farm. The objective was to evaluate the productivity and mortality of the passionfruit cv BRS Rubi do Cerrado grafted onto three species of rootstock in Terra Nova do Norte-MT. The design was a randomized block with 4 treatments BRS Rubi do Cerrado (BRS-RC) seedling plant along with those grafted onto three species of rootstock: Passiflora gibertii, Passiflora alata; Passiflora nitida. The scions were grafted through a cleft graft and the planting performed after 70 days. The evaluation was made of the total number and weight of the fruits, along with productivity and mortality of plants. Results showed that the BRS-RC, grafted onto P. gibertii and P. nitida, presented the best performance for weight of fruits, number of fruits and productivity. The cultivar that was grafted onto different rootstocks presented higher productivity in regards to the seedling plant. The BRS-RC, grafted onto P. nitida, presented a zero-mortality rate over the 16.5 months of cultivation. The rootstocks P. nitida and P. gibertii were superior to those of P. alata in reducing mortality in the passionfruit vine by Fusarium oxysporum f. sp. passiflorae. The confirmation was made of the pathogen Fusarium oxysporum f. passiflorae isolated in the experimental area in scions of the BRS-RC inoculated at 70 days of age

Characterization of biochemical behavior of sorghum (Sorghum bicolor [Moench.]) under saline stress conditions using multivariate analysis

The aim of this research was to characterize the biochemical behavior of sorghum plants under saline stress using multivariate statistical analysis methods for efficient management of Sorghum bicolor [Moench.]). The experimental design was completely randomized design composed of three saline concentrations (0, 1.5 and 2.0 M) in 10 replications. In the multivariate analysis (hierarchical method), there were distinct and sub-groups in the sorghum plant treatments. Group 1 consisted of the root parts and under this group there were two subgroups: 1.5 to 2.0 concentration (Group 1) and 2 concentration (Group 2). The increase of NaCl concentration in the roots and leaves has inverse correlation with decrease of nitrate reductase, amino acids, protein and starch. The amounts of amino acids, carbohydrates, sucrose and proline in the roots and carbohydrates, sucrose and proline in the leaves of sorghum plants are reliable biological indicators of saline stress conditions in the soil. The nitrate compound differed (p ≤ 0.05) in the sorghum plant roots; it had an average value of 0.04 μmol kg-1 of nitrate in the control treatment dry matter. The nitrate average was between 0.04 and 0.06 μmol kg-1, but without statistical difference for all concentrations.Key words: Multivariate statistics, salt concentration, proline, carbohydrate

Palma forrageira na alimentação de ovinos e caprinos no semiarido brasileiro

The This literature review aimed to discuss about the characteristics of cactus, demonstrating their use and importance in the feeding of sheep and goats in the semi-arid region, which has limitations in that time of year due to low efficiency in the rain driest months and high temperatures. As an alternative to cactus to feed these animals, it is an energy food with good flavor and has up to 90% of its composition of water. However, it has limitations on the amount of protein and fiber, not meeting the nutritional needs of the flock. Should be given to the animals in the forms of cactus meal or mixed with fresh sources of fiber.Esta revisão de literatura teve o objetivo de discorrer acerca das características da palma forrageira, demonstrando a sua utilização e importância na alimentação de caprinos e ovinos na região semi-árida brasileira, que apresenta limitações em determinada época do ano devido à baixa efetividade da chuva nos meses mais secos e de temperaturas elevadas. Sendo a palma forrageira uma alternativa para alimentação destes animais, pois é um alimento energético, com boa palatabilidade e possui até 90% da sua composição de água. No entanto, apresenta limitações quanto ao valor protéico e de fibra, não atendendo as necessidades nutricionais do rebanho. Devendo ser fornecida aos animais nas formas de farelo de palma ou in natura misturada com fontes de fibras

Nutrição de maracujazeiro

Among the factors that contribute to the profitability of the crop of yellow passion fruit, mineral nutrition of plants is one of the most important crop management. Therefore contributes to increased productivity and fruit quality, especially in tropical regions, usually of low fertility. The fertilizer can be mineral or organic origin and performed in three different stages: fertilization of foundation, development and production. Thus, this review presents the characteristics necessary for adequate nutrition to meet nutritional needs of yellow passion fruit. In this sense, the fertilization with macro most common elements, not to interfere only in growth but also on the yield and quality of the product.Entre os fatores que contribuem para a rentabilidade da cultura do maracujazeiro-amarelo, a nutrição mineral das plantas é uma dos mais importantes manejos da cultura. Pois, contribui para o aumento da produtividade e a qualidade dos frutos, principalmente em solos de regiões tropicais, geralmente de baixa fertilidade. A adubação pode ser de origem mineral ou orgânica e realizada em três etapas diferentes: adubação de fundação, formação e produção. Assim, nesta revisão expõe as características necessárias para uma nutrição adequada para suprir as necessidades nutricionais do maracujazeiro-amarelo. Neste sentido, as adubações com macro elementos mais comuns, não interferirem apenas no crescimento, mas também, no rendimento e na qualidade do produto colhido

ADUBAÇÃO NITROGENADA DE TOMATEIROS

Esta revisão de literatura teve o objetivo expor as características da adubação nitrogenada em cultivo de tomateiros. Constatando que a adubação nitrogenada deve ser realizada de acordo a necessidade da planta, produtividade e o solo a ser cultivado devendo ser realizado em parcela de acordo o desenvolvimento da planta. Onde as diferentes fontes de nitrogênio (nítrica; amoniacal; amídica) quando aplicado no solo não afetam de forma significativa a produção e a qualidade de frutos de tomate. No entanto, quando recomendado quantidade de N em abundância no solo terá a produção de tecidos suculentos e novos criando condições favoráveis ao ataque de doenças e insetos