43 research outputs found
Diagnóstico de qualidade e balanço energético na produção de pupunheira em propriedades familiares na região do Caparaó.
Estudos que apontem o fluxo energético dos sistemas de cultivo são de grande importância para a produção agrícola a fim de atingir uma agricultura mais sustentável. O objetivo deste trabalho foi caracterizar a eficiência energética na produção de palmito de pupunha através do balanço energético do sistema e de indicadores de qualidade, em duas propriedades familiares no município de Alegre/ES. Foram adotadas metodologias participativas para promover maior interação com o agricultor e sua família, e consequentemente obter maior volume de informações para a coleta de dados. O balanço energético foi realizado pela diferença entre os gastos energéticos (entrada) e a produção alcançada (saída). A propriedade 1 apresentou balanço energético positivo e superiores indicadores de qualidade, já a propriedade 2 apresentou balanço energético negativo e inferiores diagnóstico de qualidade. A propriedade 1 apresentou maior eficiência energética mostrando estar usando melhor os seus recursos na produção da pupunheira
Yacon production at different planting seasons and growing environments
Yacon is a functional food with great potential for horticultural exploitation and its cultivation demands the generation of agronomic information. To address these needs, this study was performed to evaluate the production of yacon planted in different planting seasons under two growing conditions in Brazil. The experiments were conducted in two different locations, one in the mountain region (tropical microclimate at altitude with milder temperatures) and the other in the lowland region (warm tropical microclimate with higher temperatures). At both sites, yacon was planted in four seasons: autumn (April), winter (July), spring (September) and summer (December). At harvest, the tuberous roots were evaluated for leaf area index and the variables of vegetative development and productivity of plants (for total and standard commercial roots). It was concluded that yacon cultivation in mountain conditions (tropical climate with milder temperature) promotes the development and production of yacon. Additionally, planting in the autumn for both growing conditions (mountain or lowland) promotes the development and production of yacon, including increased production of roots of better commercial grade, allowing greater economic profitability. These results indicate that temperature has an influence on the growth and yield of the tuberous roots of yacon, and milder temperatures were more favourable
Perennial herbaceous legumes used as permanent cover cropping in the Caatinga Mineira
"Parte da disserta??o de Mestrado do primeiro autor, apresentada ao Programa de P?s-Gradua??o em Produ??o Vegetal, CCA/UFVJM; projeto financiado FAPEMIG, CNPq, MDA/SAF e MDS/SESAN"O presente trabalho objetivou avaliar o comportamento e as potencialidades de leguminosas herb?ceas perenes para o uso como cobertura permanente em solos da regi?o da Caatinga Mineira, M?dio Vale do Jequitinhonha, MG, visando a introdu??o dessas plantas de cobertura em ?reas agr?colas. O experimento foi conduzido de dezembro de 2008 a julho de 2009. O delineamento experimental foi em blocos ao acaso, com seis tratamentos e quatro repeti??es. Os tratamentos foram constitu?dos pelas leguminosas: cudzu tropical (Pueraria phaseoloides), calopog?nio (Calopogonium mucunoides), amendoim forrageiro (Arachis pintoi), soja perene (Glycine wightii), estilosantes (Stylosanthes capitata, Stylosanthes macrocephala) e pela testemunha (sem a presen?a de leguminosa). Foram avaliados os seguintes par?metros: emerg?ncia das pl?ntulas; taxa de cobertura do solo; promo??o da reten??o de umidade e temperatura do solo; capacidade de inibi??o da vegeta??o espont?nea; potencial de deposi??o de folhas e de aporte de macronutrientes pela senesc?ncia de folhas; produ??o total de fitomassa seca e ac?mulo de macronutrientes na parte a?rea. A cobertura plena do solo foi alcan?ada pelo calopog?nio, amendoim forrageiro e cudzu tropical. O calopog?nio conferiu maior capacidade de reten??o da umidade e inibi??o das plantas espont?neas. Em todos os tratamentos com leguminosas a temperatura do solo foi inferior ? testemunha, a partir dos 120 dias de ciclo. Na regi?o da Caatinga Mineira, as leguminosas perenes calopog?nio e cudzu tropical, podem contribuir significativamente para o incremento de nitrog?nio, aporte de outros macronutrientes (K, P, Ca e Mg) e incremento da mat?ria org?nica do solo.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)The study objective was to evaluate the performance and potential of perennial herbaceous legumes for use as permanent soil cover in the Caatinga Mineira region MG, Brazil, for the introduction of these cover crops in agricultural areas. The experimental design was in a randomized blocks with six treatments and four replications. The treatments consisted on the leguminous: Pueraria phaseoloides, Calopogonium mucunoides, Arachis pintoi, Glycine wightii e Stylosanthes capitata, Stylosanthes macrocephala and the control (without the presence of leguminous). Were evaluated: seedling emergence and rate of soil cover, promotion of moisture retention and soil temperature, ability to inhibit the spontaneous vegetation, deposition potential of leaves and intake of macronutrients by senescence of leaves, dry matter production and accumulation of nutrients in the shoot. The full coverage of the soil was reached for Calopogonium mucunoides, Arachis pintoi and Pueraria phaseoloides. The Calopogonium mucunoides created greater capacity to retain moisture and inhibiting weeds. In all the treatments with leguminous, the soil temperature was lower than in control, from the 120 day cicle. In the region of Caatinga Mineira, the perennial leguminous Calopogonium mucunoides and Pueraria phaseoloides, could contribute significantly to the increase of the nitrogen and other macronutrients (K, P, Ca and Mg) and the increase of organic matter under the soil
Agronomic aspects of leguminous to green fertilization in the Cerrado of the High Jequitinhonha Valley
O uso intensivo e inadequado dos solos acelera sua degrada??o, sendo necess?ria a interven??o por meio de pr?ticas conservacionistas para restaurar a capacidade produtiva dos mesmos. O objetivo deste estudo foi avaliar o comportamento e desenvolvimento de diferentes leguminosas utilizadas como adubos verdes em solos de Cerrado, Alto Vale do Jequitinhonha, em Turmalina, MG. O delineamento experimental adotado foi em blocos ao acaso, com sete tratamentos e quatro repeti??es, sendo os tratamentos constitu?dos pelas leguminosas: mucuna-cinza (Mucuna nivea), mucuna-preta (Mucuna aterrima), lablabe (Dolichos lablab), feij?o-de-porco (Canavalia ensiformis), Crotalaria juncea, Crotalaria spectabilis e guandu-an?o (Cajanus cajan). O ciclo precoce de C . juncea, C. spectabilis e feij?o-de-porco favorece a inser??o destes nos sistemas de cultivo. Aos 40 dias, o feij?o-de-porco e mucuna-cinza j? cobriam o solo, com 67 e 63 %; j? o guandu-an?o e C. juncea apresentaram os maiores desenvolvimentos, nesse per?odo. Os teores de N, P e K tendem a diminuir nas avalia??es realizadas nas diferentes fases vegetativas, o que contribui para melhor escolha da ?poca de manejo das leguminosas. Crotalaria juncea, mucuna-cinza, feij?o-de-porco e mucuna-preta foram as leguminosas que se destacaram na produ??o de mat?ria seca, o que torna essas esp?cies promissoras para aduba??o verde na regi?o. As leguminosas, em sua maioria, apresentam potencial para reciclagem dos macronutrientes e aporte de N aos sistemas de produ??o.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)The intensive and inadequate use of soils accelerates its degradation, requiring the intervention by means of conservation practices to restore the productive capacity of the same. The aim of this study was to evaluate the behavior and development of different legumes used as green manure in soils of the Cerrado, High Jequitinhonha Valley in Turmalina, MG. The experimental design was in randomized blocks with seven treatments and four replications, the treatments were the leguminous: Mucuna nivea, Mucuna aterrima, Dolichos lablab, Canavalia ensiformis, Crotalaria juncea, Crotalaria spectabilis and Cajanus cajan. The early cycle of Crotalaria juncea, Crotalaria spectabilis and Canavalia ensiformis, favors the insertion of these in cropping systems. At 40 days, the Canavalia ensiformis and Mucuna nivea stood out to cover the soil with 67 and 63 %, the Cajanus cajan and Crotalaria juncea presented the highest development in this period. The contents of N, P and K tend to decrease in the evaluations realized in different vegetative stages, which contributes to better choice of the time management of legumes. Crotalaria juncea, Mucuna nivea, Canavalia ensiformis and Mucuna aterrima, were the leguminous that stood out for fitomass production, making these promising species for green manure in the region. The leguminous in your mostly, presents potential for recycling of macronutrients and the contribution of N to production systems
Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions
We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe
Forward-central two-particle correlations in p-Pb collisions at root s(NN)=5.02 TeV
Two-particle angular correlations between trigger particles in the forward pseudorapidity range (2.5 2GeV/c. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B. V.Peer reviewe
Event-shape engineering for inclusive spectra and elliptic flow in Pb-Pb collisions at root(NN)-N-S=2.76 TeV
Peer reviewe
Elliptic flow of muons from heavy-flavour hadron decays at forward rapidity in Pb-Pb collisions at root s(NN)=2.76TeV
The elliptic flow, v(2), of muons from heavy-flavour hadron decays at forward rapidity (2.5 <y <4) is measured in Pb-Pb collisions at root s(NN)= 2.76TeVwith the ALICE detector at the LHC. The scalar product, two- and four-particle Q cumulants and Lee-Yang zeros methods are used. The dependence of the v(2) of muons from heavy-flavour hadron decays on the collision centrality, in the range 0-40%, and on transverse momentum, p(T), is studied in the interval 3 <p(T)<10 GeV/c. A positive v(2) is observed with the scalar product and two-particle Q cumulants in semi-central collisions (10-20% and 20-40% centrality classes) for the p(T) interval from 3 to about 5GeV/c with a significance larger than 3 sigma, based on the combination of statistical and systematic uncertainties. The v(2) magnitude tends to decrease towards more central collisions and with increasing pT. It becomes compatible with zero in the interval 6 <p(T)<10 GeV/c. The results are compared to models describing the interaction of heavy quarks and open heavy-flavour hadrons with the high-density medium formed in high-energy heavy-ion collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V.Peer reviewe
Pseudorapidity and transverse-momentum distributions of charged particles in proton-proton collisions at root s=13 TeV
The pseudorapidity (eta) and transverse-momentum (p(T)) distributions of charged particles produced in proton-proton collisions are measured at the centre-of-mass energy root s = 13 TeV. The pseudorapidity distribution in vertical bar eta vertical bar <1.8 is reported for inelastic events and for events with at least one charged particle in vertical bar eta vertical bar <1. The pseudorapidity density of charged particles produced in the pseudorapidity region vertical bar eta vertical bar <0.5 is 5.31 +/- 0.18 and 6.46 +/- 0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15 <p(T) <20 GeV/c and vertical bar eta vertical bar <0.8 for events with at least one charged particle in vertical bar eta vertical bar <1. The evolution of the transverse momentum spectra of charged particles is also investigated as a function of event multiplicity. The results are compared with calculations from PYTHIA and EPOS Monte Carlo generators. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe
Green manure with perennial herbaceous legumes in the m?dio vale do Jequitinhonha.
O m?dio vale do Jequitinhonha apresenta condi??es clim?ticas adversas, tendendo para a semiaridez, com precipita??es anuais abaixo de 1.000 mm, demandando estrat?gias de conviv?ncia com essas condi??es. Os solos agr?colas nessas regi?es tropicais, por estarem expostos aos fen?menos clim?ticos, t?rmicos e h?dricos, necessitam de prote??o cont?nua, alcan?ada atrav?s da cobertura, viva ou morta, proporcionada principalmente por leguminosas herb?ceas perenes utilizadas na aduba??o verde. Este trabalho foi desenvolvido com o objetivo de avaliar o comportamento e as potencialidades de leguminosas herb?ceas perenes para uso como aduba??o verde, em recupera??o ao per?odo de seca, e avaliar a produ??o do quiabeiro em cultivo sobre a cobertura viva dessas leguminosas, sob manejo org?nico, na regi?o do m?dio vale do Jequitinhonha/MG. Dois experimentos foram conduzidos: o primeiro com as leguminosas cudzu tropical (Pueraria phaseoloides), calopog?nio (Calopogonium mucunoides), amendoim forrageiro (Arachis pintoi), soja perene (Glycine wightii), estilosantes campo grande (Stylosanthes capitata, Stylosanthes macrocephala) e com plantas espont?neas (controle); e o segundo com o quiabeiro cultivado em cons?rcio com essas leguminosas. O delineamento experimental utilizado nos dois experimentos foi o de blocos, nesse caso com quatro repeti??es. Observou-se que no primeiro experimento o cudzu e a soja perene restabeleceram-se na ?rea, mais influenciados pela rebrota do que pelo ressemeio; o amendoim forrageiro e o estilosantes restabeleceram-se pelos dois m?todos propagativos citados; e o calopog?nio se restabeleceu praticamente por ressemeio. As esp?cies cudzu tropical, calopog?nio, amendoim forrageiro e soja perene se destacaram para a cobertura do solo. O uso das leguminosas como cobertura permanente promoveu inibi??o e mudan?as na composi??o das esp?cies de plantas espont?neas ao longo do tempo, com destaque para o cudzu. Todas as leguminosas proporcionaram menor temperatura do solo em rela??o ao controle, com destaque para o cudzu e amendoim forrageiro. O calopog?nio se destacou entre as leguminosas com maior capacidade de reten??o da umidade do solo. O uso de leguminosas perenes como calopog?nio, cuduz tropical e soja perene, pode contribuir para o incremento de N, e a ciclagem dos macronutrientes, al?m do aumento da mat?ria org?nica sobre o solo, por meio do material senescente. Independentemente do tratamento, foram encontrados maiores valores de P, K, Mg, SB, pH e mat?ria org?nica nos primeiros 5 cm de profundidade. Os tratamentos calopog?nio, cudzu e soja perene se destacaram, para o teor de K, Mg, SB, H+Al e T em todas as profundidades do solo, com o controle tamb?m se destacando para o teor de K. Em todas as profundidades, o solo sob cudzu revelou o menor valor de pH. Amendoim forrageiro, calopog?nio e soja perene se destacaram para o teor de P na camada de 10 a 20 cm de profundidade do solo. O calopog?nio apresentou os maiores teores de mat?ria org?nica em todas as profundidades, e independentemente do tratamento, na medida em que se aumenta a profundidade do solo, observam-se valores decrescentes para o teor de mat?ria org?nica. O controle, calopog?nio, cudzu e estilosantes apresentaram o maior valor de carbono da mat?ria org?nica leve. No segundo experimento observou-se que ap?s estiagem, com in?cio do restabelecimento, cudzu tropical, soja perene e amendoim forrageiro, demonstraram consider?vel potencial de ac?mulo de mat?ria seca na parte a?rea. Ap?s o corte, o calopog?nio e o amendoim forrageiro restabeleceram-se bem, principalmente atrav?s de germina??o, proporcionada pelo banco de sementes depositado no solo e tamb?m por rebrota, no caso do amendoim forrageiro. O cudzu e a soja perene promoveram menor presen?a de plantas espont?neas. Amendoim forrageiro e calopog?nio se destacaram em proporcionar menor temperatura do solo e todas as leguminosas promoveram maior reten??o de umidade do solo, com exce??o do estilosantes, quando comparados com o controle. O quiabeiro cultivado sobre soja perene e cudzu tropical apresentou maiores alturas. A aduba??o verde com soja perene, estilosantes e cudzu tropical, proporcionou aumento no n?mero e produtividade de frutos de quiabeiro por colheita, por somat?rio de colheitas, e por classe.Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Minist?rio do Desenvolvimento Agr?rio/Secretaria de Agricultura FamiliarDisserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012.ABSTRACT The m?dio vale do Jequitinhonha is severely punished by adverse climate conditions, tending to the semiarid, with annual rainfall below 1.000 mm, then it is required strategies for dealing with these conditions. Soils in these tropical regions need continuous protection because they are exposed to extreme climate, temperature and water. Bad consequences can be minimized by alive or dead coverage which came mainly from perennial herbaceous leguminous used for green manure. This study aimed to evaluate the performance and potential of perennial herbaceous leguminous to be used as green manure on recovery at dry period, and the production of okra cultivated on these leguminous living coverage, under organic management in the region of m?dio vale do Jequitinhonha/MG. Two experiments were conducted: the first one with tropical kudzu (Pueraria phaseoloides), calopo (Calopogonium mucunoides), forage peanut (Arachis pintoi), perennial soybeans (Glycine wightii), stylosanthes (Stylosanthes capitata, Stylosanthes macrocephala) and control group; and in the second one, okra was intercropped with these leguminous. A randomized block design was used with four replicates. It was observed that in the first experiment, the perennial soybean and kudzu had re-established themselves in the area, more influenced by re-growth than by re-seeding. Forage peanut and stylosanthes were restored by the two propagation methods mentioned, and calopo was restored by re-seeding. The tropical kudzu, calopo, forage peanut and perennial soybean species stood out on soil coverage. The use of leguminous plants as permanent coverage promoted inhibition and changes in the weed species composition of the species over time, emphasing kudzu. All leguminous plants provided lower soil temperature as compared to the control group, especially the kudzu and forage peanut. The calopo stood out among the leguminous plants with a greater capacity to retain soil humidity. The use of these perennial leguminous may contribute to the increase of N, and the cycling of macronutrients besides increasing organic matter on the soil through senescent material. Regardless of the treatment, higher values of P, K, Mg, SB, pH and organic matter were found in the first 5 cm depth. The calopo, kudzu and perennial soybean treatments stood out for the content of K, Mg, SB, T and H + Al in all soil depths, with the control group also standing out for the content of K. In all depths, the soil under kudzu showed the lowest pH value. Peanut forage, calopo and perennial soybean stood out for P content from 10 to 20 cm of soil depth. The calopo showed the highest levels of organic matter at all depths, regardling of the treatment. As soil depth increases, values of organic matter content decreases. The control group, calopo, kudzu and stylosanthes showed the greatest amount of carbon from light organic matter. In the second experiment it was observed that after dry time, beginning the restoration, kudzu tropical, perennial soybean and forage peanut, showed considerable potential for dry matter accumulation in shoots. After cutting, forage peanut and calopo had a great recoverage, mainly through germination, provided by the seed bank in the soil and also in the case of forage peanut re-growth. The kudzu and perennial soybean promoted lower re-infestation of weeds. Calopo and the forage peanut were better in providing lower soil temperature and all leguminous plants promoted a greater retention of soil humidity, except for stylosanthes, when compared to control group. The okra grown on soybeans and tropical kudzu presented higher heights. Green manure with perennial soybean, Kudzu and stylosanthes increased the number and the productivity of okra by harvest, by the sum of harvests, and by class