Yield performance and leaf nutrient levels of coffee cultivars under different plant densities

Cultivares de cafeeiro (Coffea Arabica L.) adaptadas às regiões de cultivo, com população de plantas otimizada e adequado estado nutricional são premissas para a obtenção de produções elevadas de café. Estudou-se a produção trienal de café e o teor foliar de macronutrientes de cultivares de cafeeiro em função das densidades de plantio. Foram utilizados os cultivares Catuaí Amarelo (IAC 47), Obatã (IAC 1669-20), Acaiá (IAC 474-19) e Icatu Amarelo (IAC 2944) nas populações de 2.500 plantas ha-1 com duas plantas por cova; e, 5.000, 7.519 e 10.000 plantas ha-1 com uma planta por cova. As plantas foram adubadas de modo homogêneo, porém, sem calagem. À medida que a população de cafeeiros aumentou, a produtividade trienal de café aumentou, a produção de frutos por planta diminuiu e os teores foliares de fósforo (P), potássio (K) e enxofre (S) aumentaram. Nos cafeeiros sob adensamento encontrou-se igual ou maior teor de macronutrientes do que naqueles sob espaçamento convencional, sendo que os maiores teores foram observados nas cultivares de porte alto, e os menores, na cultivar Obatã, de porte baixo. Nos cafeeiros das covas com uma planta observou-se maior produção de café e menores concentrações de P, Ca e S do que naqueles das covas com duas plantas. No geral, os cultivares e as populações de cafeeiros estavam com teores de N e S acima dos limites de referência citados na literatura, mas com teores dos demais macronutrientes dentro da faixa adequada.

ROOT-GROWTH AND MINERAL-NUTRITION OF CORN HYBRIDS AS AFFECTED BY PHOSPHORUS AND LIME

The effects of triple superphosphate (TS) and liming on macronutrient accumulation and root growth of Pioneer 3072 and Cargill 505 com hybrids were studied. Com plants were grown up to 30 days in pots with 7 L of a dark red Latosol sandy loam (Haplortox). Lime was applied to raise base saturation to 30, 50, and 70%, in two levels of phosphorus (P) fertilization with TS (0 and 200 ppm P). There was an increase in root surface due to lime only in pots without TS, with no effects on plant growth or nutrition. Both com hybrids responded to P fertilization, but Pioneer yielded more dry matter than Cargill. The roots of Cargill were thicker and, when in TS presence, were longer and had a larger surface than Pioneer. There was an increase in macronutrient uptake in the P fertilized pots. Pioneer required more nutrients and showed a higher efficiency in acquiring and utilizing the nutrients from the soil. A higher response of Pioneer in dry matter and nutrient acquisition was more related to the physiological efficiency than to root morphology.

Selenato e selenito na produção, nutrição mineral e biofortificação com selênio em cultivares de alface

SELENATE and SELENITE on YIELD, MINERAL NUTRITION and BIOFORTIFICATION WITH SELENIUM IN LETTUCE CULTIVARSSelenium is an important antioxidant element associated with physiological processes in plants, microorganisms, animals, and humans. However, its mode of action and essentiality in plants are still disputed. In Brazil, information on Se in agricultural crops is extremely scarce, though there are indications that low levels of Se are being consumed by the population. The objective of this study was to evaluate the effect of selenate and selenite on yield, mineral nutrition and biofortification with Se of lettuce cultivars. The experiment was arranged in a completely randomized factorial design 5 x 3 x 2, with five lettuce cultivars (Maravilha de Verao, Rafaela, Great Lakes, Veneranda, and Vera), three Se concentrations (0, 10 and 20 mu mol L(-1)) and two forms of Se (selenate and selenite), with four replicates. Results indicate that selenate application is more appropriate for biofortification of lettuce cultivars, while the effect of selenite proved to be more toxic. The application of selenate results in increased S shoot concentrations, while selenite reduced P concentrations, and both Se forms decreased micronutrient concentrations. No genotypic variation among lettuce cultivars was observed for Se concentration, and little variation was observed for shoot dry matter yield and S, Mg, Mn, and Fe levels.

Root growth and nutrient accumulation in cover crops as affected by soil compaction

Crop rotation using cover crops with vigorous root systems may be a tool to manage soils with some degree of compaction. Root and shoot growth as well as nutrient accumulation by summer species suitable for crop rotation in tropical areas were studied at different subsoil compaction levels. Crotalaria juncea (Indian hemp), Crotalaria spectabilis (showy crotalaria), Helianthus annuus (sunflower), Pennisetum americanum (pearl millet) and Sorghum bicolor (guinea sorghum) were grown for 40 days in pots 33.5 cm high with 10 cm internal diameter. Soil in the pots had uniform bulkdensity of 1.25 Mg m-3 for the top and bottom 15 cm sections. Bulk densities of 1.31, 1.43, 1.58 and 1.70 Mg m-3 Were established in the 3.5 cm middle section. H. annuus and P. americanum had the highest early macronutrient accumulation. The grasses S. bicolor and P. americanum yielded twice as much shoot dry matter as the other species. Root growth generally decreased with increasing soil bulk density with C. spectabilis less affected than other species. Although the grasses were more sensitive to high soil penetration resistance, they showed higher root length densities at all compaction levels. P. americanum had the highest potential to be used as cover crop due to its high root density at high soil penetration resistances, vegetative vigour and ability to accumulate macronutrients. © 2002 Elsevier Science B.V. All rights reserved.

Produção de composto orgânico a partir de residuos de plantas medicinais

Extraction of active principles from medicinal plants generates wastes usually discharged. This process does not extract minerals from plant tissues, which may be considered of great value in organic composting. Wastes of 81 medicinal plant species processed at Centroflora/Anidro industry were analyzed for macro and micronutrients, and according to the results, three different ways to elaborate the compost were proposed: a) wastes of medicinal plants with high content of a specific mineral, aiming to fertilize soils where would be cultivated species that need high quantities of that mineral; b) wastes with mineral contents in order to support specific failures on mineral content of a soil; c) wastes of the eleven richest species in each nutrient that should elevate all mineral contents in soil.

Matéria seca, concentração e acúmulo de nutrientes em mudas de Eucalyptus grandis em função da idade

E grandis seedlings of Bofete progeny, cultivated in nurseries of Eucatex Florestal, were collected at ages of 55, 69, 83, and 97 days, separated into leaves, stem, and roots. The seedlings were then placed in identified paper bags, and oven-dried until weight became constant. They were then weighed and chemically analyzed for the determinate of dry matter production, concentrations and accumulation of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn in the several seedling ages. The distribution of total dry matter weight complied with the following descending order: leaf > stem > roots. Conversely to expectations, the highest concentrations of nutrients occurred in leaves for N and Mn only. Seedling hardened process resulted in N and S deficiency. The sequence of macronutrient concentration in seedlings at the time of shipment was the following: leaf > root > stem for N; root = stem > leaf for P; leaf = root = stem for K; stem > root > leaf for Ca; root > leaf > stem for Mg and S. All macronutrient concentrations in organs decreased with age, except for Ca. Concentrations of Cu, Fe, and Zn in all seedling specimens decreased with age. The sequence of micronutrient concentrations in seedling specimens at the time of shipment was the following: root >stem = leaf for B; root > stem > leaf for Cu and Fe; root > leaf > stem for Zn, and leaf > stem > root for Mn. At the time of shipment, at 97 days of age, K was the most extracted macronutrient of all, followed in a descending order by Ca, N, Mg, P, and e S. At the end of the seedling production rotation, Mn was the most extracted micronutrient, followed by Fe, Zn, Cu, and B.

Desenvolvimento do manjericão (Ocimum basilicum L.) cultivado em solução nutritiva com diferentes níveis de magnésio

The aim of this experiment was to study the influence of several levels of magnesium on development and essential oil content of basil, plants were cultivated using Hoagland and Arnon (1950) number one 1 complete solution, containing 48.6 mg L -1 and with decreasing levels of magnesium (24.3 mg L -1 and 12.1 mg L -1). The experimental design was completely randomized, in a factorial scheme 3x3, which is, three levels of magnesium and three harvest times, with three replications each. The parameters evaluated were the stem length, leaf dry mass, stem dry mass, roots dry mass, absolute growth rate (AGR), relative growth rate (RGR), net assimilatory rate (NAR), leaf area ratio (LAR), leaf mass ratio (LMR), dry mass distribution on several organs, stem and leaf/root ratio and essential oil yield, all those measured in three harvest time 30, 60 and 90 days after transplantation (DAT). Plants cultivated with the lower levels of magnesium showed no symptoms of deficiency, but showed differences in the parameters studied. Essential oil yield was higher at 30 DAT for plants cultivated with 12.1 mg L -1 the magnesium. Our results suggests that Hoagland and Arnon (1950) no 1 complete solution overestimates the level of magnesium, as has been observed in several other plant species.

Omissāo de macronutrientes no crescimento e no estado nutricional de capim-elefante (cv. Mott) cultivado em solução nutritiva

The objective of this work was to evaluate the effect of omission of macronutrients in the growth and the nutritional state of elephant-grass plants (Pennisetum purpureum Shum cv. Mott). The experiment was developed in the FCAV/UNESP, in Jaboticabal-SP,Brazil, using nutrient solution. The experimental design was completely randomized blocks, with seven treatments (the complete solution proposed by Hoagland & Amon (1950) and the individual omission of N, P, K, Ca, Mg and S, in these solution), in three repetitions. Pre-germinated plants were placed in pot (5 dm3), containing the nutrient solution, which was aerated constantly during the experimental period and the respective treatments, with three replications each. Weekly, the height of the plants, the leaf number, apex diameter and number of tillers were evaluated as well as plant nutritional state. The omission of N, P, K, Ca, Mg and S limited the production of dry weight of shoot the elephant grass, compared to the full treatment. The deficiency of a macronutrient, in addition to promoting reduction of its content in the shoot, resulted in reducing the accumulation of most macronutrients, with resultant morphological changes, translated as characteristic symptoms of deficiency.

Deficiências de macronutrientes em plantas de soja cv. BRSMG 68 (Vencedora) cultivada em solução nutritive

Soybean is a crop of great importance for Brazil, and knowledge of their nutritional status allows production and high quality products. Thus, the present work aimed to evaluate the culture of the soybean cv. BRSMG 68 (Vencedora), submitted to macronutrients omission on the development, nutritional status and the visual symptomatology of nutrient deficiency. The design used was completely randomized, with seven treatments that corresponded to the complete (macro and micronutrients) solution and the individual omission of N, P, K, Ca, Mg and S. The treatments were applied two weeks after the emergency of the soybean. The nutrient solution was constantly oxygenated and replaced weekly, and the pH monitored daily remained around 5. After six weeks of application of the treatments, the height of the plants, number of leaves, stem diameter was evaluated, matter dry accumulated in the roots, it leaves aerial and the nutritional state and the characterization of the visual symptoms. The macronutrient deficiency promoted a decrease in production of root and shoot dry mass of soybean cultivar BRSMG 68 (Vencedora) in nutrient solution, for the full treatment. The most limiting nutrient for dry matter production of soybean compared to complete treatment were N, S and K, with decreases of 90, 76 and 73%, respectively. Individual omissions resulted in morphological changes, which were translated by characteristic visual symptoms of nutritional deficiency of the respective nutrient.

Omissão de macronutrientes na nutrição e no crescimento da cana-de-açúcar cultivada em solução nutritiva

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Crescimento e desordem nutricional em pimenteira malagueta cultivada em soluções nutritivas suprimidas de macronutrientes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estado nutricional de mangueiras determinado pelos métodos DRIS e CND

Different procedures for the integrated method of diagnosis and recommendation may influence the accuracy of foliar diagnosis of mango. Thus, the objective of this study was to compare the diagnosis of nutritional status of mango obtained by different methods of assessing nutritional status, comparing multivariate relations (method CND) with bivariate relationships (DRIS) i.e., variations in the use of specific or preliminary standards and a logarithmic transformation of the data. The macro and micronutrient leaf analysis results of 63 mango orchards of Lower-middle São Francisco River Valley, Brazil, were used. To interpret nutritional status the Potential Response to Fertilization (PRA) criteria was used. The CND and DRIS methods, with and without logarithmic transformation and using specific or preliminary standards, which showed similar performance in assessing the nutritional status of the mango in Lower-middle San Francisco. Mango orchards in the semiarid region of northeast Brazil, the micronutrient deficiencies (Zn, Fe and Cu) were more frequent than macronutrient deficiency.

Extensive impact of saturated fatty acids on metabolic and cardiovascular profile in rats with diet-induced obesity: A canonical analysis

Background: Although hypercaloric interventions are associated with nutritional, endocrine, metabolic, and cardiovascular disorders in obesity experiments, a rational distinction between the effects of excess adiposity and the individual roles of dietary macronutrients in relation to these disturbances has not previously been studied. This investigation analyzed the correlation between ingested macronutrients (including sucrose and saturated and unsaturated fatty acids) plus body adiposity and metabolic, hormonal, and cardiovascular effects in rats with diet-induced obesity. Methods: Normotensive Wistar-Kyoto rats were submitted to Control (CD; 3.2 Kcal/g) and Hypercaloric (HD; 4.6 Kcal/g) diets for 20 weeks followed by nutritional evaluation involving body weight and adiposity measurement. Metabolic and hormonal parameters included glycemia, insulin, insulin resistance, and leptin. Cardiovascular analysis included systolic blood pressure profile, echocardiography, morphometric study of myocardial morphology, and myosin heavy chain (MHC) protein expression. Canonical correlation analysis was used to evaluate the relationships between dietary macronutrients plus adiposity and metabolic, hormonal, and cardiovascular parameters. Results: Although final group body weights did not differ, HD presented higher adiposity than CD. Diet induced hyperglycemia while insulin and leptin levels remained unchanged. In a cardiovascular context, systolic blood pressure increased with time only in HD. Additionally, in vivo echocardiography revealed cardiac hypertrophy and improved systolic performance in HD compared to CD; and while cardiomyocyte size was unchanged by diet, nuclear volume and collagen interstitial fraction both increased in HD. Also HD exhibited higher relative β-MHC content and β/α-MHC ratio than their Control counterparts. Importantly, body adiposity was weakly associated with cardiovascular effects, as saturated fatty acid intake was directly associated with most cardiac remodeling measurements while unsaturated lipid consumption was inversely correlated with these effects. Conclusion: Hypercaloric diet was associated with glycemic metabolism and systolic blood pressure disorders and cardiac remodeling. These effects directly and inversely correlated with saturated and unsaturated lipid consumption, respectively. © 2013 Oliveira Junior et al.; licensee BioMed Central Ltd.

Crescimento inicial e nutrição de cedro (Cedrela fissilis Vell.) em função de doses de nitrogênio

We aimed to evaluate the effects of nitrogen rates in early growth, SPAD index, content and accumulation of nutrients in cedar seedlings. The experiment was carried out in a plastic greenhouse and the seedlings were grown in plastic pots filled with 20 dm-3of Rhodic Hapludox, arranged inrandomized blocks with four replications. Rates of 0, 40, 80, 120 and 160 mg dm-3N were tested. Fertilization up to 160 mg dm-3N promoted increases in SPAD index and early growth of plants, beyond greater absorption of N,P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn. Overall, lower N rates limited growth but not the absorption of nutrients by cedar plants. In leaves, the only nutrien taffected was the B which their content was reduced with increasing of N rate. Increased of nitrogen fertilization changed the Cu distributionin plants, since increased Cu content in roots and reduced their content in stem. Higher N rates promoted higher accumulation of all nutrients due to the increase of dry matter. Nitrogen fertilization changed the dynamic of nutrient absorption in cedar. With 160 mg dm-3N, the amount absorbed followed the order: N>S>Ca>K>Mg>P>Fe>Mn>B> Zn> Cu.

Nutritional strategies of physically active subjects with muscle dysmorphia

Background: The aim of this study was to identify dietary strategies for physically active individuals with muscle dysmorphia based on a systematic literature review. Method. References were included if the study population consisted of adults over 18 years old who were physically active in fitness centers. We identified reports through an electronic search ofScielo, Lilacs and Medline using the following keywords: muscle dysmorphia, vigorexia, distorted body image, and exercise. We found eight articles in Scielo, 17 in Medline and 12 in Lilacs. Among the total number of 37 articles, only 17 were eligible for inclusion in this review. Results: The results indicated that the feeding strategies used by physically active individuals with muscle dysmorphia did not include planning or the supervision of a nutritionist. Diet included high protein and low fat foods and the ingestion of dietary and ergogenic supplements to reduce weight. Conclusion: Physically active subjects with muscle dysmorphia could benefit from the help of nutritional professionals to evaluate energy estimation, guide the diet and its distribution in macronutrient and consider the principle of nutrition to functional recovery of the digestive process, promote liver detoxification, balance and guide to organic adequate intake of supplemental nutrients and other substances. © 2013 Contesini et al.; licensee BioMed Central Ltd.