Liv Soares Severino

Desenvolvimento e produção de duas cultivares de mamoneira sob estresse salino

With the objective of studying the behavior of two cultivars BRS Paraguacu and BRS Energy of castor bean (Ricinus communis L.), irrigated with four levels of electrical conductivity of irrigation water (ECw: 0.7; 2.7; 4.7 and 6.7 dS m-1, at 25 °C), an experiment was conducted in a randomized design with 3 replications, in a factorial scheme of 4 x 2. The variables measured were: plant height, stem diameter, leaf area, number of leaves and water consumption by plant at 80 and 100 days after sowing (DAS), number of days for emission of first inflorence and height of first cluster at 100 DAS, days to harvest, number of fruits in the 1st cluster, weight of fruits, and 10 seeds at 150 DAS. The salinity of the irrigation water significantly affected the plant height, stem diameter, number of leaves, leaf area and water consumption starting from ECw 4.7 dS m-1 at 80 and 100 DAS of both cultivars. The cultivar BRS Energy showed early emission of the first inflorence and a greater height of cluster, while, the cultivar BRS Paraguacu showed lesser fruits and seeds and had a higher weight of 10 seed.

Volume de recipientes e composição de substratos para produção de mudas de mamoneira

A mamoneira (Ricinus communis L.)e uma oleaginosa bem adaptada ao cultivo na regiao semi-arida por sua rusticidade e resistencia ao estresse hidrico. Seu plantio e tradicionalmente feito por sementes, mas o uso de mudas pode se tornar atraente como estrategia para melhor aproveitamento da curta estacao chuvosa. Para adocao desta tecnologia, a definicao de aspectos tecnicos como volume de recipientes, composicao do substrato e periodo de permanencia da muda no viveiro sao fundamentais para o exito da tecnica. Conduziu-se experimento em casa-de-vegetacao da Embrapa Algodao em Campina Grande, com sementes da cultivar de mamona de porte medio BRS Nordestina, em delineamento de blocos casualizados com 4 repeticoes e 25 tratamentos em distribuicao fatorial 52, sendo os fatores cinco volumes de recipientes e cinco composicoes de substratos. Entre 15 e 43 dias apos a emergencia (DAE) foram feitas cinco coletas destrutivas semanais para obtencao de dados de altura, diâmetro caulinar, area foliar, numero de folhas e materia seca da parte aerea e radicular. Com os dados obtidos calculou-se o tamanho da folha. Detectaram-se efeitos significativos dos tratamentos em todas as variaveis estudadas. O crescimento das mudas estabilizou-se aproximadamente aos 36 DAE, independente do volume do recipiente. Os substratos compostos por mistura de areia com esterco bovino ou casca de amendoim propiciaram o melhor crescimento das mudas, enquanto aqueles contendo bagaco de cana ou mucilagem de sisal foram os piores. Recipientes de 2 L de volume foram os mais adequados para a producao de mudas de mamoneira.

Substratos para produção de mudas de mamoneira compostos por misturas de cinco fontes de matéria orgânica

O plantio de mamona (Ricinus communis L.) atraves de mudas pode ser uma alternativa para um melhor aproveitamento da curta estacao chuvosa do semi-arido brasileiro, porem ainda nao se dispoe de informacoes basicas para o emprego desta tecnica. Na formulacao de substratos para producao de mudas de mamona, as caracteristicas fisicas, principalmente a aeracao, sao fatores de grande importância. O presente estudo objetivou avaliar a composicao de substratos utilizando misturas de solo, esterco bovino, casca de amendoim, mucilagem de sisal, bagaco de cana e cama de frango. Utilizou-se delineamento em blocos casualizados com 12 tratamentos e quatro repeticoes. Sementes da cultivar BRS Nordestina foram semeadas em sacos plasticos de 17 x 28cm, contendo misturas dos materiais a serem testados. Valores de altura, area foliar, numero de folhas e diâmetro caulinar foram registrados semanalmente entre 15 e 43 dias apos a emergencia. Na ultima coleta tambem se registraram a massa seca da parte aerea e das raizes. O substrato composto por solo + casca de amendoim + cama de frango + mucilagem de sisal propiciou o melhor crescimento das mudas. A cama de frango contribuiu para o enriquecimento quimico do substrato, enquanto a casca de amendoim e a mucilagem de sisal contribuiram para adequar as caracteristicas fisicas de aeracao e retencao de agua.

Redistribuição de nutrientes em folhas de pinhão-manso entre estádios fenológicos

Nutrient redistribution from mature leaves to growing structures is an important process in plant physiology. Each nutrient is redistributed in a different rate and time. This study aimed to quantify redistribution of macronutriens and minor nutrients in Jatropha curcas leaves through five phenological phases (expanding leaf, young leaf, mature leaf, senescing leaf, and dry leaf). It was observed that the nutrients P, K, Cu, and Zn are intensively redistributed from older to younger jatropha leaves, while N, Ca, Mg, Fe, and Mn are poorly redistributed. Leaf senescence causes a loss of the nutrients that are not redistributed because they will need to be re-absorbed for supporting the growth of new structures in the plant.

Casca de mamona associada a quatro fontes de matéria orgânica para a produção de mudas de pinhão-manso

Castor hull combined with four organic matter sources for physic nut seedling production Substrates consisting of mixtures of soil and organic materials have usually been recommended for production of physic nut (Jatropha curcas L.) seedlings. Castor hull is a residue produced in large quantities during the hulling process. This residue contains high amounts of macronutrient s. The objective of this study was to evaluate four organic materials for mixing with soil and castor hull. The experiment was conducted in a greenhouse at EMBRAPA Cotton Research Center between October and December 2006. The treatments were arranged in a complete randomized design with four replications and two plants per plot. Treatments were a mixture of soil and castor hull with one of the following materials: garbage compost, bovine manure, sewage sludge and castor presscake. The Control was a mixture of soil and castor hull. At 55 days after sowing, data on plant height, number of leaves, leaf area, stem diameter , dry weight of shoots and roots and leaf content of N, P, K, Ca, Mg and S were measured. All substrates were found suitable for production of physic nut seedlings, however the use of soil with castor hull only showed the lowest seedling

Comprimento das estacas e parte do ramo para formação de mudas de pinhão-manso

Jatropha curcas is traditionally propagated by seed. However, in several situations the vegetative propagation is an important alternative and its technology needs to be developed. The objective of this study was to evaluate how the length and the portion of the branch from where the cuttings are extracted, influence the rooting and growth capacity of Jatropha cuttings. The treatments were arranged in a 3 x 4 factorial design, with three cutting positions (apical, middle and basal) and four cutting lengths (10, 15, 20, and 25 cm). A completely randomized design with four replications and ten cuttings per plot was adopted. At 70 days after planting, the cuttings were evaluated for the number of sprouts and branches, branch length, number of leaves, leaf area, number of roots, and dry mass of shoots and roots. The position from where the cuttings are extracted (apical, middle or basal) did not influence its capacity for rooting and the growth of the seedlings. The cutting length influences the initial growth, and the best growth was obtained in cuttings of around 22 cm.

Comportamento ingestivo de ovinos alimentados com rações contendo quatro níveis de inclusão do farelo de mamona

Ingestive behavior of sheep fed diets containing four levels of castor meal The aim of this work was to evaluate the effect of the replacement of four levels of a soybean meal by detoxified castor meal in rations fed to seven month-old Ω Morada Nova x Ω WDB (without defined breed) crossbred lambs, average 18 kg BW, on their ingestive behavior. The experiment was conducted in a completely randomized design with four treatments and five replicates. Continuous (feeding time, rumination, other activities and idleness) and punctual (salt consumption, water ingestion, urination and defecation) activities, as well as eating ef ficiency, rumination efficiency, eating time, rumination time, total chewing time, number of ruminal bolus, time of jaw movements per ruminal bolus and number of jaw movements per ruminal bolus were evaluated. The variables feeding time, rumination, other activities,

Zoneamento e época de plantio para o algodoeiro no Norte do Estado do Espírito Santo

O zoneamento e a definicao da epoca de plantio foram realizados no intuito de se estabelecer as areas e periodos convenientes a exploracao do algodoeiro herbaceo (Gossypium hirsutum L. r. latifolium) no Estado do Espirito Santo. O plantio em epoca adequada reduz os riscos de perdas na producao por falta ou excesso de agua nos estadios criticos da cultura e contribui para a otimizacao do controle de pragas e doencas. Para a identificacao da epoca de plantio e zoneamento, as exigencias do algodoeiro foram relacionadas aos dados de precipitacao pluvial, do periodo chuvoso, aos fatores ambientais (temperatura e umidade do ar) relevo e outras informacoes extraidas do Mapa de Unidade Naturais do Norte do Estado do Espirito Santo. Dez municipios apresentaram condicoes de cultivo, mas oito foram classificados como aptidao restrita devido ao relevo acidentado e alta umidade relativa do ar e apenas dois classificados como aptidao preferencial, onde as condicoes para cultivo sao otimas.

Validating a probe from GhSERK1 gene for selection of cotton genotypes with somatic embryogenic capacity

Substantial progress is being reported in the techniques for plant transformation, but successful regeneration of some genotypes remains a challenging step in the attempts to transform some recalcitrant species. GhSERK1 gene is involved on embryo formation, and its overexpression enhances the embryogenic competence. In this study we validate a short GhSERK1 probe in order to identify embryogenic cotton genotypes using RT-qPCR and blotting assays. Cotton genotypes with contrasting somatic embryogenic capacity were tested using in vitro procedures. High expression of transcripts was found in embryogenic genotypes, and the results were confirmed by the RT-PCR-blotting using a non-radioactive probe. The regeneration ability was confirmed in embryogenic genotypes. We confirmed that GhSERK1 can be used as marker for estimating the somatic embryogenesis ability of cotton plants.

Lâminas de irrigação e populações de plantas na mamoneira cv BRS Energia

Objetivando estudar os efeitos de lâminas de irrigacao em populacoes de plantas da mamoneira BRS Energia, foi conduzido um experimento em esquema fatorial 4 × 4, sendo quatro lâminas de irrigacao (311,74; 460,40; 668,53 e 850,54 mm) e quatro populacoes de plantas (27.777, 33.333, 41.666 e 55.555 plantas ha -1 ), com quatro repeticoes. O delineamento foi de blocos ao acaso com parcelas dispostas em faixas. O trabalho foi executado na Fazenda Experimental da Embrapa Algodao, localizada no municipio de Barbalha - CE. Por meio do metodo de irrigacao por aspersao, estimaram-se as lâminas de acordo com a distância da linha central de aspersores em relacao as faixas irrigadas. Na lâmina de 668,53 mm a BRS Energia obteve-se as principais respostas para altura de planta (111,43 cm); area foliar (8.111,78 cm 2 ) e produtividade (2.678,38 kg ha -1 ). Na populacao de 33.333 plantas ha -1 verificou-se a maior taxa de crescimento absoluto (1,99 cm dia -1 ), enquanto em 55.555 plantas ha -1 deteve o maior indice de area foliar (3,25 m 2 m -2 ). Todas as populacoes se comportaram semelhante quanto a produtividade.