1,721,301 research outputs found
Calcário na forma de micropartículas aplicado no sulco de semeadura aumenta produtividade do feijoeiro
Get PDFRESUMO A aplicação de solução de micropartículas de calcário (CaCO3) no sulco de semeadura pode alterar rapidamente os atributos químicos do solo, na zona de emissão de raízes, e aumentar a produtividade do feijoeiro-comum. O objetivo deste estudo foi o de testar essa hipótese em solos com diferentes características químicas. Foram realizados dois experimentos. No primeiro, avaliaram-se doses de soluções de CaCO3 (0, 1050, 2100, 4200, 8400 e 12600 g ha-1), aplicadas no sulco de semeadura, em dois anos agrícolas consecutivos. No segundo, o CaCO3 (1050 g ha-1) foi aplicado, ou não, no sulco de semeadura, em quatro ambientes. Os delineamentos experimentais foram em blocos ao acaso. A aplicação de solução de micropartículas de CaCO3, no sulco de semeadura do feijoeiro, aumentou os valores de pH e reduziu a saturação por Al+3 no solo. Os teores de Ca, K e a saturação por bases no solo não foram influenciadas pela adição de CaCO3 no sulco. O uso de micropartículas de CaCO3 no sulco de semeadura aumentou a produtividade de grãos do feijoeiro-comum. Os resultados sugerem que a aplicação de micropartículas de CaCO3 no sulco de semeadura foi eficiente para alterar os atributos químicos do solo no leito de semeadura e proporcionar incrementos significativos de produtividade de grãos do feijoeiro-comum
Application of lime, phosphogypsum and fertilization rates affect soil fertility and common bean development in no-tillage system in a Cerrado Oxisol
Get PDFABSTRACT. There is a lack of information about the effects of interactions among lime, phosphogypsum (PG) and fertilization on soil fertility and their effects on common bean yields in the tropics. This study aimed to determine the effects of annual application of PG and limestone and rates of fertilization on the chemical attributes of soil, fertilization efficiency, yield components and the grain yield of the common bean. The study was performed for three growing seasons in an acidic Oxisol. The experimental design was randomized blocks in a 4x4 factorial scheme. The treatments consisted of lime, lime + PG, PG, and control (without corrective application) with four fertilization rates. In an acidic and low-fertility Cerrado soil, limestone or limestone + PG applied annually at 1/3 of the total rate in a no tillage system increased the common bean yield and the efficiency of the fertilization, although the improvement of the soil acidity indicators did not reach the desired levels. The application of soluble fertilizers to provide adequate and balanced amounts of nutrients provided greater yield gains and improved soil fertility compared to surface liming without fertilization, but the combination of the two practices resulted in the greatest benefits to both plant and soil fertility.</p
Cover Crops as Affecting Soil Chemical and Physical Properties and Development of Upland Rice and Soybean Cultivated in Rotation
Get PDFCover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determine the effects of cover crops (cultivated in the offseason) in the soybean-upland rice rotation (cultivated in the summer season) on the soil chemical and physical properties, yield components and grain yield of the cash crops. The experimental design was a randomized block design in factorial scheme 4 × 2 with six replications. Treatments were composed by four cover crops: fallow, millet (Pennisetum glaucum) + Crotalaria ochroleuca, millet + pigeon pea (Cajanus cajans), and millet + pigeon pea + Urochola ruziziensis in the offseason with one or two cycles of cover crops, with rice (Oryza sativa) or soybean (Glycine max) in the summer season. Cover crops alone provided no changes in soil chemical properties. However, the rotation cover crops/cash crops/cover crops/cash crops reduced pH, Al and H + Al and increased Ca, Mg, K and Fe contents in the soil. The cover crops millet + pigeon pea and millet + pigeon pea + U. ruziziensis improved soil physical properties in relation to fallow, especially in the 0–0.10 m soil layer. In spite of the improvement of the soil physical properties after two years of rotation with cover crops and cash crops, the soil physical quality was still below the recommended level, showing values of macroporosity, S index and soil aeration capacity lower than 0.10 m3/m3, 0.035 and 0.34, respectively. Upland rice production was higher under mixtures of cover crops than under fallow, mainly because of soil physical changes done by these mixtures of cover crops. Soybean grain yield was similar under all cover crops tested, but was higher after the rotation cover crops/upland rice/cover crops than after only one cycle of cover crops. Keywords: crop rotation, no-tillage system, sustainable agriculture, tropical agriculture, rice, soybea
Adubação fosfatada e aplicação de Penergetic na produtividade do feijoeiro comum.
Get PDFO uso da tecnologia Penergetic tem sido proposta para a obtenção de maiores produtividades das culturas visando maior disponibilidade dos nutrientes do solo, notadamente o fósforo. O objetivo do trabalho foi determinar a produtividade de grãos e componentes de produção do feijoeiro comum afetados pela adubação fosfatada e pela aplicação de Penergetic. O experimento foi conduzido em condições de campo sob irrigação, por dois anos agrícolas (2012 e 2013). O delineamento experimental foi em blocos casualizados no esquema fatorial 4 x 2. Os tratamentos constaram da combinação de quatro doses de fósforo aplicados ao solo (0, 40, 80 e 120 kg ha-1 de P2O5) com a presença e ausência de aplicação de Penergetic. A adubação fosfatada proporcionou incrementos significativos na produtividade de grãos e componentes de produção do feijoeiro comum nos dois anos de cultivo. O uso de Penergetic independente da dose de fósforo utilizada proporcionou maior produtividade de grãos do que os tratamentos sem aplicação do produto nos dois anos de cultivo. No ano de 2013, a aplicação de Penergetic proporcionou maior produtividade de grãos (5313 kg ha-1) numa menor dose de P (82,2 kg ha-1 de P2O5) do que na ausência do produto (3903 kg ha-1) na maior dose de P (120 kg ha-1 de P2O5)
Produtividade do feijão-comum afetado por população de plantas
Get PDFA população de plantas afeta diretamente a incidência de doenças e plantas daninhas, colheita, acamamento, aproveitamento de água e fertilizantes e gastos com sementes da maioria das culturas agrícolas. Além disso, é importante se determinar a população ideal de plantas por área das novas cultivares de feijão-comum visando obter o máximo potencial produtivo de cada material genético. O objetivo desse trabalho foi de determinar os efeitos de população de plantas nos componentes de produção e produtividade de grãos da cultivar de feijão-comum BRS Estilo. O delineamento experimental foi em blocos ao acaso com cinco tratamentos e seis repetições. Os tratamentos foram compostos pelo número de sementes por metro de BRS Estilo (4, 8, 12, 16 e 20 sementes m-1). O aumento da população de plantas proporcionou redução na massa de matéria seca, número de vagens por planta, número de grãos por vagem, massa de 100 grãos e produtividade de grãos do feijão-comum cultivar BRS Estilo
Effects of grain-producing cover crops on rice grain yield in Cabo Delgado, Mozambique
Get PDFABSTRACT Besides providing benefits to the environment such as soil protection, release of nutrients, soil moisture maintenance, and weed control, cover crops can increase food production for grain production. The aim of this study was to evaluate the production of biomass and grain cover crops (and its respective effects on soil chemical and physical attributes), yield components, and grain yield of rice in Mozambique. The study was conducted in two sites located in the province of Cabo Delgado, in Mozambique. The experimental design was a randomized block in a 2 × 6 factorial, with four repetitions. Treatments were carried out in two locations (Cuaia and Nambaua) with six cover crops: Millet (Pennisetum glaucum L.); namarra bean (Lablab purpureus (L.) Sweet), velvet beans (Mucuna pruriens L.), oloco beans (Vigna radiata (L.) R. Wilczek), cowpea (Vigna unguiculata L.), and fallow. Cover crops provided similar changes in chemical and physical properties of the soil. Lablab purpureus, Vigna unguiculata, and Mucuna pruriens produced the highest dry matter biomass. Vigna unguiculada produced the highest amount of grains. Rice grain yields were similar under all cover crops and higher in Cuaia than Nambaua.</jats:p
Genotype selection and addition of fertilizer increases grain yield in upland rice in Suriname.
Get PDFThe upland rice farmers in Suriname use local varieties and low level technologies in the field. As a result, the upland rice grain yield is low, at about 1 000 kg ha-1. Our objective was to evaluate the use of upland rice cultivars from Suriname and Brazil, and the effect of nitrogen, N, phosphorus, P, and potassium, K, fertilizers on cultivation variables. We undertook four field trials in the Victoria Area, in the Brokopondo District, using a randomized block design each with four replications. The most productive rice varieties were BRS Esmeralda (grain yield 2 903 kg ha-1) and BRS Sertaneja (2 802 kg ha-1). The highest grain yield of 2 620 kg ha-1 was achieved with a top dressing application of 76.41 kg N ha-1 20 days after sowing. For P, the highest grain yield of 3 085 kg ha-1 was achieved with application of 98.06 kg ha-1 P2O5 applied at sowing. An application rate of 31.45 kg ha-1 of K2O at sowing achieved the highest grain yield of 2 952 kg ha-1. Together, these application rates of N, P and K resulted in rice grain yield of about 3 000 kg ha-1, which is three times greater than the national average for upland rice. We demonstrate that the use of improved rice varieties matched to the local conditions, and application of appropriate fertilizers, are management practices that can result in significant increases in rice grain yield in Suriname
Compactação sobre o sulco de plantio e tratamento de sementes na produtividade do arroz de terras altas
Get PDFEste trabalho objetivou determinar o efeito da compactação sobre o sulco de plantio e do tratamento de sementes na produtividade do arroz de terras altas cultivado sob sistema plantio direto (SPD). Foram conduzidos quatro experimentos, o primeiro e o terceiro em área de pastagem de Urochloa brizantha, o segundo em área de soja e o quarto em área de pastagem de Urochloa decumbens. No primeiro e no segundo foram comparadas três pressões de compactação sobre o sulco de plantio, no delineamento de blocos ao acaso, com seis repetições. No terceiro e no quarto foram comparados três pressões de compactação sobre o sulco de plantio e dois tratamentos de sementes, em blocos ao acaso, esquema fatorial, comseis repetições no terceiro e 12 no quarto experimento. No primeiro experimento, as pressões de compactação foram 25 kPa, 42 kPa e 228 kPa e, nos outros três, a pressão de 228 kPa foi substituída pela de 340 kPa. Os tratamentos de sementes foram: T0 - sem tratamento e T1 - fipronil + piraclostrobina + tiofanato metílico. A compactação sobre o sulco de plantio aumentou de forma linear a produtividade do arroz. O tratamento de sementes resultou em maiores produtividades do arroz cultivado no SPD sobre palhada de braquiária
Soybean growth and yield under cover crops.
Get PDFThe use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops) and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1) than both in the pearl millet (4.772 kg ha-1) and common bean straw treatments (5,200 kg ha-1). The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield
Yield, biomass production and nutrients accumulation of super early genotype of common bean.
Get PDFThis work aimed to study the biomass production and nutrient uptake during plant development and nutrients exported by the grains of a super early genotype (SEG) of common bean. The irrigated field experiment was done during the 2016 growing season (winter season), under no-tillage system conditions, in the Cerrado region. Experimental design was in complete randomized block in split plots scheme, with four replications. Main plots comprised SEG of common bean (Colibri ? check cultivar and CNFC 15874) and subplots were nine times of plant collection (14, 21, 28, 35, 42, 49, 56, 63 and 70 days after plant sowing, DAS) with separation in leaves, stem and pods. Absorption of nutrients by the shoots of SEG CNFC 15874 follows the decreasing order N> K> Ca> Mg> P> S> Fe> Zn >Mn >Cu. The maximum accumulation of nutrients in the leaves and stem of the SEG was at 42 DAS (full flowering stage) and in the pods between 63 to 70 DAS (physiological maturation). Nitrogen, K, P, Ca, S, Fe, Zn, Mn and Cu was the order of accumulated nutrients in grains of super early genotypes. Nitrogen, P and Cu was the nutrients with higher amount in the grains of SEG. IPR Colibri had higher number of pods, mass of grains, total and pods biomass production, nutrients accumulation and grain yield than CNFC 15874. Nutrients should be available to SEG of common bean between 14-21 DAS (third trifoliolate leaf)
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