Alfalfa, considered one of the most important forage worldwide, requires a base saturation in the soil of approximately 80%, and this is a factor that can limit the expansion of cultivation of this crop in tropical soils that are predominantly acidic. The objective of this study was to evaluate the influence of base saturation levels on the development of alfalfa in soil of the Brazilian Cerrado. The experiment was conducted in the greenhouse, whose experimental units consisted of plastic pots with a capacity of 2 dm 3 . The experimental design was a completely randomized design with six treatments and five repetitions. The treatments consisted of six levels of base saturation (10,
The objective of this study was to analyze the effect of soil fertilization with sulfur-based fertilizers, sulfate and elemental sulfur forms on biomass production, nutrient characteristics of sorghum and soil chemical properties. The experiment was carried out in a 4 x 4 factorial scheme (four sulfur sources: single superphosphate, agricultural gypsum, elemental sulfur powder and elemental sulfur granulated with bentonite, and four sulfur doses: 0, 40, 80, 120 mgdm-3) using four replications in a completely randomized design, being cultivated in pots under greenhouse conditions. The sorghum was cultivated for a period of 51 days after emergence of the seedlings. The shoot dry mass, shoot macronutrients content, root and soil and pH of the soil were evaluated. There were interactions between sources and sulfur doses in the variables such as shoot dry mass, sulfur in the root, sulfur and calcium in the soil. Elemental sulfur (granulate) showed lower concentrations of phosphorus, sulfur and N:S ratio in the shoot. The concentrations of potassium, calcium and magnesium did not show significant differences, both for the shoot and the root. The pH of the soil was reduced depending on the sources and doses of elemental sulfur. The sources and doses of sulfur did not influence the levels of phosphorus, potassium, and magnesium in the soil. The elemental sulfur in the form of powder is the best source of sulfur for forage sorghum cultivated in soil with alkaline pH.
In the state of Mato Grosso, Brazil, wheat is an alternative to the current production system, mainly in irrigated crops, with new cultivars improved for this environment and system. The objective was to determine the evapotranspiration of the irrigated wheat crop and the dual coefficients of cultivars for the Brazilian Midwest. The experiment was conducted in the field using 12 weighing lysimeters and mini-lysimeters, filled by soil monoliths. The wheat cultivars BRS-254 and BRS-394 were used in the first and second years, respectively. Reference evapotranspiration was obtained by the Penman-Monteith equation and crop evapotranspiration by the mass difference in the lysimeters. Basal crop coefficient and soil water evaporation coefficient were determined according to the crop development stages in both years of cultivation. The mean ETc and ETo values were 3.87, 3.49 mm d-1 and 4.10 and 3.23 mm d-1, respectively, in the first and second cultivation cycles, with higher values of ETc recorded in the reproductive stages of the crop, flowering and grain filling. The basal crop coefficients and soil water evaporation coefficients estimated by weighing lysimeters composed of soil monoliths are: Kcb - 0.42, 0.78, 0.94, 0.74 and 0.47 and Ke - 0.72, 0.52, 0.39, 0.58 and 0.13 for the cultivar BRS-254, and Kcb - 0.28, 0.27, 0.65, 0.98 and 0.66 and Ke - 1.04, 0.96, 0.65, 0.34 and 0.51 for the cultivar BRS-394, at the stages of emergence, tillering, flowering, maturation and harvest, respectively.
Cowpea (Vigna unguiculata (L.) Walp.) constitutes one of the principal protein sources for the economically constrained low-income sector. The composition of the wood ash reveals macro and micronutrients, which form an alternative source of high-added value fertilizers, very suitable for low-cost farming systems. The aim of this study was to estimate the use of wood ash as a fertilizer during the early developmental stages of the cowpea. A randomized block design with four replications was selected for the experiment. It was performed in a greenhouse, in pots 1.5 dm-3 capacity, to which five wood ash doses (0, 8, 16, 24 and 32 g dm-3) were added. The following variables were analyzed, viz. plant height, stem diameter, number of leaves, chlorophyll index, shoot and root dry masses, mass and number of nodules, water consumption and water use
A disponibilidade de nutrientes é um fator que pode afetar as trocas gasosas das culturas. O objetivo desse estudo foi avaliar os efeitos da aplicação dos micronutrientes zinco (Zn) e boro (B) na fotossíntese, condutância estomática e transpiração de plantas de milho cultivadas em Cambissolo Eutrófico durante a fase vegetativa. O estudo foi realizado em casa de vegetação com a condução de dois experimentos concomitantemente. Em um experimento aplicou-se níveis de doses de zinco (0, 2, 4 e 6 mg dm-3). No outro, foram aplicadas doses de boro (0, 1, 2 e 3 mg dm-3). O delineamento utilizado foi o inteiramente casualizado com cinco repetições. O estudo teve duração de 50 dias após a emergência das plantas. As variáveis avaliadas foram: taxa de fotossíntese (Tf), transpiração foliar (E) e condutância estomática (gs). A partir desses parâmetros, foi possível calcular a eficiência momentânea (EUAm = Tf/E) e intrínseca (EUAi = Tf/gs) do uso da água. A aplicação de doses de Zn e B resultou em diferenças significativas (P < 0,01) em todas as variáveis. A dose de 6 mg dm-3 de Zn resultou em menor fotossíntese e maior condutância estomática e transpiração. As doses de B utilizadas causaram aumento linear na fotossíntese, condutância estomática e transpiração. Observou-se que as doses dos micronutrientes Zn e B aumentam significativamente as trocas gasosas de plantas de milho em estágio vegetativo e há redução da taxa fotossintética a partir da dose de 3,75 mg dm-3 de Zn.
O Cerrado brasileiro apresenta uma certa previsibilidade em relação a pluviosidade, caracterizando-se em dois períodos: um chuvoso e outro seco. A oferta de água e seu consumo se tornam relevantes, para os diversos cultivos, isso porque a água é o principal preditor do desenvolvimento vegetal. A cultura do trigo surge como alternativa para produção no Brasil central, sendo importante sua adaptabilidade e eficiência nas condições do ambiente. O objetivo do trabalho foi submeter três cultivares de trigo, BRS264, BRS394, BRS404, indicadas para região central do Brasil, submetidas à cinco tensões hídricas: 12; 24; 36; 48 e 60kPa; em casa de vegetação, dispostos em vasos sob o delineamento em blocos ao acaso, esquema fatorial (5X3), com cinco repetições. O Monitoramento das irrigações foi a partir da leitura do sensor de capacitância (modelo- ML3, Delta T). As características avaliadas foram altura de plantas, número de espiguetas por espiga, número de grãos por espiga e índice de colheita. As cultivares BRS394 e BRS264 possuem as melhores respostas para as variáveis: altura de plantas, número de espiguetas por espiga e índice de colheita, em relação a cultivar BRS404 que demonstra menor adaptabilidade sob deficiência hídrica, A tensão hídrica do solo de 12KPa obteve os melhores resultados em relação as outras tensões.
Water availability, fertilizer management and crop rotation are fundamental to the sustainability of agriculture and food security. Thus, the objective of this study was the determination of crops coefficients, verification and comparison of methods of estimation and determination of the evapotranspiration of irrigated wheat. The experiment was carried out during two consecutive years, in which BRS 254 varieties were cultivated in 2016 and BRS 394 in the year 2017. The evapotranspiration was estimated and determined using the dual kc methodology, FAO-56, with plants grown in 12 lysimeters filled with soil monoliths, and the loss of water by evaporation measured by weighing small-lysimeters. Evapotranspiration was also determined by the water balance method. The results measured in the lysimeters (standard method) were compared with the data simulated by the dual kc method and determined by method of soil water balance, in order to determine the accuracy and efficiency of the methods used. The coefficients used to determine the efficiency of the methods were the RMSE, the RSR and the confidence index "c". The total evapotranspiration of the crop in both years of cultivation was 360 mm, with mean values of 3.87 mm d-1 for cultivar BRS 254 and 4.10 mm d-1 for cultivar BRS 394. The basal crops coefficients in the emergence, tillering, flowering, maturation and harvest stages were 0.42, 0.78, 0.94, 0.74 and 0.47 for cultivar BRS 254 and 0.28, 0.27, 0.65, 0.98 and 0.66 for cultivar BRS 394. The soil water evaporation coefficients at the respective stages are 0.72, 0.52, 0.39, 0.58 and 0.13 for cultivar BRS 254 and 1.04, 0.96, 0.65, 0.34 and 0.51 for cultivar BRS 394. Ke represents on average about 47% of the evapotranspiration of the irrigated wheat crop. Between methods tested, lysimeter is the best to wheat transpiration followed by FAO method and soil water balance. The use of any methods should consider the objectives and resources availability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.