721 research outputs found

    NUTRIENTS CYCLING AND ACCUMULATION IN PEARL MILLET AND PAIAGUAS PALISADEGRASS BIOMASS IN DIFFERENT FORAGE SYSTEMS AND SOWING PERIODS

    Get PDF
    Developed the study objective of was to evaluate nutrient cycling and accumulation in pearl millet and Paiaguas palisadegrass biomass under different forage systems and sowing periods in integrated crop-livestock. The experiment followed a randomized block design with a 5 × 2 factorial arrangement and three replications, under five forage systems (monocropped pearl millet, monocropped Paiaguas palisadegrass, pearl millet intercropped in rows with Paiaguas palisadegrass, pearl millet intercropped between rows of Paiaguas palisadegrass and pearl millet oversown and intercropped with Paiaguas palisadegrass) and in two sowing periods (February and March). The results showed that Paiaguas palisadegrass monocropped or intercropped in rows or between rows, exhibited the highest nutrient cycling and accumulation in the remaining biomass. Nutrient accumulation the under all of the examined forage systems showed the following decreasing order: K > N > Mg > Ca > P > S. Potassium was the nutrient exhibiting the greatest accumulation in the biomass and it exhibited a higher percent decrease with decomposition time. The first sowing period for the forage systems led to higher nutrient cycling and accumulation in the biomass. Intercropped systems through in integrated crop-livestock showed a promising technique to maintain the nutrient cycling and accumulation with sustainability

    Critical periods of sorghum and palisadegrass in intercropped cultivation for climatic risk zoning.

    Get PDF
    The objective of this work was to define critical periods for sorghum and palisadegrass cultivated on crop-livestock integrated systems under water deficit. An experiment was carried out in a completely random block design with four treatments (control and interruption of water supply in three periods) and three replicates. Water supply was interrupted until soil water humidity was close to permanent wilting point at the phases: germination of palisadegrass seeds; start of tillering of palisadegrass and initiation of panicles of shorghum; start of shorghum flowering. Water deficit starting at palisadegrass germination delayed intital development of the plants because of the reduction in tillering. Water restriction at panicle initiation phase and at sorghum flowering determined reduction of grain production. Critical periods for intercrop of sorghum and palisadegrass correspond to palisadegrass germination phase and flowering and panicle inititation phase of sorghum

    Crop coefficient estimated by degree-days for ‘Marandu’ palisadegrass and mixed forage

    Get PDF
    Considering profitability in pasture-based systems, investigating parameters affecting crop coefficients for irrigation management becomes important. In this experiment, we determined the crop coefficient of ‘Marandu’ palisadegrass based on accumulated degree-days and estimated plant water consumption under single (‘Marandu’ alisadegrass) and mixed (‘Marandu’ palisadegrass + black oats + Italian ryegrass) cropping regimes. The research was conducted at the Luiz de Queiroz College of Agriculture in Piracicaba, São Paulo, Brazil, between 2016 and 2017. Evapotranspiration was assessed using weighing lysimeters while crop evapotranspiration was calculated using mean weight variation. Reference evapotranspiration and degree-days were estimated. Data were obtained from an automated weather station. Equations and regression models relating crop coefficient with accumulated degree-days were generated for two seasons (spring/summer and autumn/winter) and evaluated for two year-cycles, from 2015 to 2018. The results showed better prediction accuracy for the single cropping system in spring/summer 2017–18. Highlights The model for determinating crop coefficient (Kc) by accumulated degree-days showed efficient for use in determination local. The use of the degree days for determination Kc is more vantage because only necessary to measure the air temperature (maximum and minimum). The equations for determining crop coefficient by accumulated degree days for the spring/summer season in Marandu palisade grass cultive show more precision that in mixture forage system.Considering profitability in pasture-based systems, investigating parameters affecting crop coefficients for irrigation management becomes important. In this experiment, we determined the crop coefficient of ‘Marandu’ palisadegrass based on accumulated degree-days and estimated plant water consumption under single (‘Marandu’ alisadegrass) and mixed (‘Marandu’ palisadegrass + black oats + Italian ryegrass) cropping regimes. The research was conducted at the Luiz de Queiroz College of Agriculture in Piracicaba, São Paulo, Brazil, between 2016 and 2017. Evapotranspiration was assessed using weighing lysimeters while crop evapotranspiration was calculated using mean weight variation. Reference evapotranspiration and degree-days were estimated. Data were obtained from an automated weather station. Equations and regression models relating crop coefficient with accumulated degree-days were generated for two seasons (spring/summer and autumn/winter) and evaluated for two year-cycles, from 2015 to 2018. The results showed better prediction accuracy for the single cropping system in spring/summer 2017–18. Highlights The model for determinating crop coefficient (Kc) by accumulated degree-days showed efficient for use in determination local. The use of the degree days for determination Kc is more vantage because only necessary to measure the air temperature (maximum and minimum). The equations for determining crop coefficient by accumulated degree days for the spring/summer season in Marandu palisade grass cultive show more precision that in mixture forage system

    Nitrogen fertilization (15 NH4 NO3) of palisadegrass and residual effect on subsequent no-tillage corn.

    Get PDF
    ABSTRACT - Nitrogen is required in large amounts by plants and their dinamics in corn and perennial forages intercropped is little known. This study analyzed the efficiency of nitrogen fertilization (15NH4NO3) applied after corn grain harvest to palisadegrass (Brachiaria brizantha cv. Marandu) in intercrops sown at two times, as well as the N residual effect on the subsequent corn crop. The field experiment was performed in Botucatu, São Paulo State, in southeastern Brazil, on a structured Alfisol under no-tillage. The experiment was arranged in a randomized block design in a split plot scheme with four replications. The main plots consisted of two intercropping systems (corn and palisadegrass sown together and palisadegrass sown later, at corn top-dressing fertilization). The subplots consisted of four N rates (0, 30, 60, and 120 kg ha-1 N). The subplots contained microplots, in which enriched ammonium nitrate (15NH4NO3) was applied at the same rates. The time of intercrop sowing affected forage dry matter production, the amount of fertilizer-derived N in and the N use efficiency by the forage plants. Nitrogen applied in autumn to palisadegrass intercropped with corn, planted either at corn sowing or at N top-dressing fertilization, increased the forage yield up to a rate of 60 kg ha-1 The amount of fertilizer-derived N by the forage plants and the fertilizer use efficiency by palisadegrass were highest 160 days after fertilization for both intercrop sowing times, regardless of N rates. Residual N did not affect the N nutrition of corn plants grown in succession to palisadegrass, but increased grain yield at rates of 60 and 120 kg ha-1 N, when corn was grown on palisadegrass straw from the intercrop installed at corn fertilization (top-dressing). Our results indicated that the earlier intercropping allowed higher forage dry matter production. On the other hand, the later intercrop allowed a higher corn grain yield in succession to N-fertilized palisadegrass. RESUMO - O nitrogênio é requerido em grandes quantidades pelas plantas e sua dinâmica no consórcio entre milho e forrageiras tropicais perenes é pouco conhecida. Objetivou-se avaliar a eficiência de utilização da adubação nitrogenada (15NH4NO3) no capim-marandu (Brachiaria brizantha cv. Marandu), proveniente de duas épocas de consórcios com o milho, realizadas após a colheita da cultura granífera, bem como o efeito residual no milho cultivado em sucessão. O experimento foi conduzido na Faculdade de Ciências Agronômicas da UNESP em Botucatu, SP, em Nitossolo Vermelho sob sistema plantio direto. O delineamento experimental foi em blocos casualizados em parcelas subdivididas. As parcelas foram constituídas pelas épocas de consórcio: milho e capim-marandu semeados simultaneamente; e capim-marandu semeado na adubação de cobertura do milho. As subparcelas foram compostas pelas doses de 30, 60 e 120 kg ha-1 de N, aplicadas no capim-marandu após a colheita da cultura do milho. Nas subparcelas, foram alocadas microparcelas para aplicação de nitrato de amônio enriquecido (15NH4NO3) nessas mesmas doses. A época de implantação do consórcio influenciou a produção de massa de matéria seca da forrageira, a quantidade de N na planta proveniente do fertilizante e a eficiência de utilização do N pelas plantas forrageiras. A aplicação de N no outono no capimmarandu, implantado por meio do consórcio com o milho, tanto na semeadura quanto na adubação nitrogenada de cobertura, proporcionou aumento de produtividade da forrageira até a dose de 60 kg ha-1. Os maiores acúmulos de N e a eficiência de utilização do fertilizante pelo capim-marandu, oriundo de ambas as épocas de consórcio, ocorreram aos 160 dias após a fertilização, independentemente das doses de N. O residual das doses de N, aplicadas no capimmarandu, não interferiu na nutrição nitrogenada do milho em sucessão, porém incrementou a produtividade de grãos nas doses de 60 e 120 kg ha-1 de N, quando o cereal foi cultivado sobre palhada proveniente do consórcio implantado na adubação de cobertura do milho. Com base nos resultados, pode-se inferir que a implantação antecipada do consórcio proporciona maior produtividade de massa de matéria seca da forrageira, enquanto quando implantado mais tarde propicia maior produtividade de grãos do milho em sucessão à forrageira adubada com N

    Suprimento combinado de nitrogênio com potássio para o capim-marandu: características morfogênicas e produtivas

    Get PDF
    The objective of this work was to study morphogenic characteristics, and dry matter production of roots and shoots of marandu palisadegrass (Brachiaria brizantha cv. Marandu) submitted to combinations of nitrogen and potassium, in a nutritive solution, employing silica as substrate. The experiment was carried out in a greenhouse during the summer. It was used a 5² fractionated factorial scheme with 13 combinations of nitrogen and potassium, which were distributed in a randomized block design, with four replications. The nitrogen × potassium interaction was significant for the number of tillers and leaves, for leaf area, for shoots and root section dry mass, for total length and surface and specific length and surface in the roots. Production of aerial part dry mass positively correlated with the number of tillers and leaves and grass leaf area. Nitrogen rates modulated the root system development, and the root specific length and surface decreased when high rates of nitrogen and potassium were supllied. Nitrogen and potassium influence Marandu palisadegrass morphogenic characteristics, which are determinant for grass dry matter production.Objetivou-se estudar as características morfogênicas e a produção de massa seca da parte aérea e das raízes do capim-marandu (Brachiaria brizantha cv. Marandu) submetido a combinações de nitrogênio e potássio, em solução nutritiva, empregando-se sílica como substrato. O experimento foi realizado em casa de vegetação, no verão. Utilizou-se o esquema fatorial 5² fracionado, com 13 combinações de nitrogênio e potássio, distribuídas em delineamento de blocos ao acaso, com quatro repetições. A interação nitrogênio × potássio foi significativa para número de perfilhos e de folhas, área foliar, massa seca da parte aérea e de raízes, comprimento e superfície totais e comprimento e superfície específicas nas raízes. A produção de massa seca da parte aérea correlacionou-se positivamente com número de perfilhos e de folhas e área foliar do capim. As doses de nitrogênio se mostraram moduladoras do desenvolvimento do sistema radicular e o comprimento e a superfície específicos diminuíram quando fornecidas altas doses desses nutrientes. O nitrogênio e o potássio influenciam as características morfogênicas do capim-marandu, que são determinantes da produção de massa seca da gramínea

    Growth of marandu palisadegrass subjected to strategies of intermittent stocking

    Get PDF
    Grazing strategies alter sward leaf area patterns of growth, affecting herbage accumulation and utilisation. The objective of this experiment was to evaluate the growth of marandu palisadegrass (Brachiaria brizantha cv. Marandu) swards subjected to strategies of intermittent stocking. The experiment was carried out in Piracicaba, São Paulo, Brazil, from October/2004 to September/2005. Swards were grazed at 95 and 100% canopy light interception (LI) to post-grazing heights of 10 and 15 cm, following a 2 × 2 factorial arrangement with four replications in a randomised complete block design. The response variables evaluated were: crop growth rate, relative growth rate, net assimilation rate, leaf area ratio and leaf weight ratio. In early and late spring, the highest crop growth rate was recorded for treatment 95/15 (11.2 and 10.1 g m-2 day-1, respectively), along with high values of net assimilation rate (4.4 and 6.9 g m-2 day-1, respectively), leaf area ratio (0.0095 and 0.0103 m-2 g-1, respectively) and leaf weight ratio (0.56 and 0.56 g g-1, respectively). To compensate reductions in net assimilation rate plants made some morphological and physiological adjustments increasing leaf area and leaf weight ratio. Relative growth rate and net assimilation rate were 26 and 50% higher, respectively, on swards grazed at 95% than at 100% LI. In early spring treatments 100/10 and 95/15 resulted in the highest relative growth rate (0.086 and 0.059 g m-2 day-1, respectively). Treatment 95/15 resulted in the most favourable pattern of growth (crop growth rate, relative growth rate, net assimilation rate), particularly during the transition period between winter and spring.Estratégias de pastejo alteram a área foliar dos pastos, interferindo em seus padrões de crescimento e afetando o acúmulo e a utilização de forragem. O objetivo desse experimento foi avaliar o crescimento de pastos de capim-marandu (Brachiaria brizantha cv. Marandu) submetidos a estratégias de lotação intermitente. O experimento foi realizado em Piracicaba, SP, Brasil, de Outubro/2004 a Setembro/2005. Os pastejos foram realizados quando o dossel atingia 95 ou 100% de interceptação luminosa (IL) até as alturas pós-pastejo de 10 e 15 cm, seguindo um arranjo fatorial 2 × 2 com 4 repetições e um delineamento de blocos completos casualizados. Avaliaram-se a taxa de crescimento da cultura, a taxa de crescimento relativo, a taxa de assimilação líquida, a razão de área foliar e a razão de peso foliar. No início e final de primavera a maior taxa de crescimento da cultura foi registrada para o tratamento 95/15 (11.2 e 10.1 g m-2 dia-1, respectivamente), associada a altos valores de taxa de assimilação líquida (4.4 e 6.9 g m-2 dia-1, respectivamente), razão de área foliar (0.0095 e 0.0103 m-2 g-1, respectivamente) e razão de peso foliar (0.56 e 0.56 g g-1, respectivamente). Para compensar reduções em taxa de assimilação líquida a planta se ajustou morfológica e fisiologicamente aumentando a razão de área foliar e razão de peso foliar. A taxa de crescimento relativo e a taxa de assimilação líquida foram, respectivamente, 26% e 50% superiores nos pastos manejados com 95% relativamente àqueles com 100% de IL. No início de primavera os tratamentos 100/10 e 95/15 resultaram na maior taxa de crescimento relativo (0.086 e 0.059 g m-2 dia-1, respectivamente). O tratamento 95/15 resultou no padrão mais favorável de crescimento (taxas de crescimento da cultura, crescimento relativo e assimilatória líquida), particularmente durante o período de transição entre inverno e primavera

    Forage Legumes in Tropical Regions: Recent Advances and Future Challenges

    Get PDF
    Nitrogen input in tropical pastures increases forage and animal productivity. Forage legumes can fix atmospheric nitrogen and are the most economical way to add this nutrient to the soil. Our objective was to report the benefits of forage legumes in tropical pastures and possible strategies to implement different forage legumes. In tropical conditions, such as in Brazil, the use of forage legumes is still scarce. Even with low legume adoption on tropical pastures, forage legumes can provide ecosystem services. Increased animal productivity is the first ecosystem service provided by these legumes, mainly due to the addition of nitrogen that is typically the most limiting nutrient on tropical soils and yet the most important driver of plant growth and development. Legumes also provide an opportunity to increase nitrogen cycling in grassland, reducing grassland degradation. Pastures that include legumes have greater litter quality than grass monocultures, increasing soil organic matter at a faster rate. Legumes improve diet nutritive value and animal performance, resulting in reduced enteric methane emissions per unit of animal product. Additionally, legumes are generally associated with lower nitrous oxide emissions than N-fertilized grass swards and reduce the carbon footprint from the system due to nitrogen manufacture, transport, storage, and application. However, the greatest challenge in tropical pastures is to increase the adoption of forage legumes. It is necessary to understand the role of different legumes in the pasture environment. Some legumes have high herbage accumulation and biological nitrogen fixation potential, but they have low canopy stability; nonetheless, they could be used on short-lived pastures as well as integrated crop-livestock systems. When the objective is to achieve grass-legume stability in mixed pastures, it is necessary to use clonal propagation legumes and provide appropriate defoliation management to minimize light competition among plant communities

    How much of nitrogen from fertilizer is absorbed by palisadegrass when intercropped with corn?

    Get PDF
    The study evaluates the influence of Palisadegrass in the use of N fertilizer, according to forms of implantation of Palisadegrass intercropped with corn in Brazil

    Palisadegrass effects on N fertilizer dynamic in intercropping systems with corn.

    Get PDF
    Corn grain yield, nitrogen (N) fertilizer efficiency and distribution to corn alone and three forms of corn and palisadegrass (Urochloa spp.) intercropping implantation was investigated. A field experiment with 15N labeling fertilizer was performed in randomized block design. No form of palisadegrass intercropping implantation affected corn grain yield, total N accumulation and N use efficiency (NUE), which were 8.7 t ha-1, 205 kg ha-1 and 37% respectively. The palisadegrass produced on average 1.9 t of dry mass, absorbing a maximum of 6 kg ha-1 or 5.5% of N fertilizer during corn growing. Furthermore, the palisadegrass did not affect N fertilizer distribution in soil-plant system, in which 28.2% was recovered in the soil and 40.4% in the plants (corn + palisadegrass). The results show that for the three intercropping implantation methods the palisadegrass did not compete with corn for N fertilizer
    corecore