Lúcia Helena Garófalo Chaves

Growth of Jatropha irrigated with saline water in greenhouse.

Considerando as potencialidades de uso do pinhao manso (Jatropha curcas L.) como fonte energetica e a carencia de resultados de pesquisa relativos ao seu cultivo, realizou-se este trabalho com o fim primordial de se estudar os efeitos da salinidade da agua de irrigacao sobre o crescimento das plantas, em ambiente protegido. A pesquisa foi desenvolvida entre abril e outubro de 2007, no Centro de Tecnologia e Recursos Naturais (CTRN) da UFCG-PB. As plantas foram cultivadas em lisimetros de drenagem (200 L), contendo 230 kg de material de solo devidamente adubado, nao-salino, nao-sodico, classificado como Argissolo Acinzentado eutrofico. Os tratamentos consistiram de cinco niveis de condutividade eletrica da agua de irrigacao - CEa (0,6; 1,2; 1,8; 2,4 e 3,0 dS m-1, a 25 oC), no delineamento experimental em blocos casualizados, com quatro repeticoes, sendo cada parcela constituida pela media de duas plantas cultivadas em lisimetros separados. Avaliaram-se altura de planta, diâmetro caulinar, numero de folhas e area foliar aos 37, 58, 79, 100, 121, 142 e 163 dias apos a semeadura; ao final do periodo de estudos, o pinhao-manso irrigado com agua de CEa de 3,0 dS m-1 teve a altura de planta, o diâmetro caulinar, o numero de folhas e a area foliar reduzidos em 9,07, 17,63, 23,41 e 42,58%, respectivamente.

The role of green rust in the environment: a review

Iron(II)-iron(III) hydroxy-salts known as green rusts (GRs) initially were identified and studied as corrosion products of steel and iron. Recently they were discovered as minerals present in hydromorphic soils and sediments. Different studies have suggested that GRs, due to their high reactivity, play an important role in the fate and transport of many contaminants in suboxic soils, sediments and aquifers where microbial reduction rates are limited by low carbon content. Also, GRs have considerable potential for applications such as water-purification processes and gas adsorbents. However, as GRs are only a transient state during the reduction of ferric iron and are converted to more stable forms, it is still necessary to continue studies about their behavior.

Propriedades químicas do solo aluvial da Ilha de Assunção - Cabrobó (Pernambuco)

The alluvial soil of the Assuncao Island, in the Sao Francisco River, Cabrobo, State of Pernambuco, Brazil, has been intensively cultivated with annual crops under irrigation. The present yields are unsatisfactory due to the use of inadequate agricultural practices that are not sustainable. This study aimed to survey the soil chemical properties in an area of 1,131 ha by collecting 1,053 samples in the 0-0.30 m surface soil layer. The samples were analyzed for chemical properties and the data were analyzed using descriptive statistics. The obtained results indicated that there was higher variability for aluminum, potassium and phosphorus concentration and for the percentage of sodium saturation. The lowest variability was observed for soil pH. The data did not present a normal distribution. Most soil samples presented low aluminum, organic matter, and phosphorus concentrations. The soil pH, CEC, calcium, magnesium, and potassium concentration were interpreted as appropriate for most crops and were classified as normal regarding the percentage of sodium saturation.

Cadmium and copper adsorption on bentonite: effects of pH and particle size

Reactions of heavy metals with clay minerals are important in determining metal fates in the environment. However, the adsorption process of these metals by the bentonite has been extensively investigated. The objectives of this work were to assess the ability of bentonite clay to adsorb cadmium and copper and to study the effects of pH and particle size upon these metals adsorption. Adsorption isotherms were obtained from batch adsorption experiments, with increasing cadmium and copper concentrations (5-200 mg L-1). To find out the effects of pH and particle size on adsorption, the experiments were conducted at pH 4; 5 and 6 using particles sizes of < 0.5 mm and 0.5 to 2.0 mm . The difference between initial and final cadmium and copper concentrations was assumed to be the amount adsorbed by bentonite. The bentonite adsorbed more copper than cadmium, both metals adsorption increased with increasing pH for both particle sizes. No effect of particle size was observed. Experimental data were best fitted to Langmuir model.

Fenologia e produção do pinhão-manso cultivado com diferentes fontes de adubação

Objetivou-se com este trabalho descrever os periodos de formacao de folhas novas, abscisao foliar, inflorescencia e maturacao dos frutos do pinhao-manso, Jatropha curcas L., bem como, determinar algumas variaveis de producao desta especie em dois ciclos de cultivo adubada com diferentes fontes de adubacao no municipio de Remigio-PB. Utilizou-se o delineamento em blocos casualizados com cinco tratamentos e quatro repeticoes. Os tratamentos foram constituidos por diferentes fontes de adubacao. Durante os meses de maio de 2007 a novembro de 2009 fez-se avaliacoes mensais dos eventos fenologicos e de producao do pinhao-manso. Independente do tratamento utilizado, a formacao de folhas novas foi observada durante o periodo chuvoso e a abscisao foliar durante os meses mais frios e os de maior estiagem. A floracao, no primeiro ciclo de cultivo, iniciou-se com o fim da estacao chuvosa com a utilizacao do composto orgânico II (F3), ja no segundo ciclo, as primeiras inflorescencias foram observadas no inicio da estacao chuvosa nas plantas adubadas com composto orgânico I (F2) e esterco de curral (F5). Em todos os tratamentos o tempo verificado entre a emissao das inflorescencias ate a maturacao fisiologicas dos frutos foi de aproximadamente 120 dias. Na primeira colheita, as fontes de adubacao nao diferiram entre si em nenhuma variavel de producao, entretanto, na segunda colheita, alem de haver um aumento na producao, o composto orgânico I (F2) e o esterco de curral (F5) foram os que promoveram os melhores resultados.

Crescimento, distribuição e acúmulo de cobre e zinco em plantas de pinhão-manso

Researches concerning the extraction of heavy metals by Jatropha curcas L. plants are still preliminary and incomplete. With the prospect of this plant to be used in phytoremediation of polluted soils, this study aimed to evaluate the effect of copper and zinc in the initial development of Jatropha curcas L. and accumulation and distribution of these elements in this plant. Two experiments were carried out in design completely randomized with three replications; the first one with five copper (0; 25; 50; 75; 100 mg dm-3) and the second with four zinc (0; 50; 100; 150 mg dm-3) treatments. At 50; 70; 90 and 110 DAS, were evaluated: plant height, stem diameter and leaf area. At the end of the experiment the plants were harvested and assessed the levels of copper and zinc in plant tissues. Soil samples were collected from each pot and subjected to chemical analysis. The Jatropha curcas L plants, during the experimental period are tolerant to the treatments, however, copper and zinc levels in soil above 75 and 50 mg dm-3, respectively, affect their growth. The copper and zinc concentrations in the plants were ranked in the following order, respectively: leaf > roots > stem; stem > leaf > root. Zinc translocation was higher than copper in the plants.

Fate of nickel ion in (II-III) hydroxysulphate green rust synthesized by precipitation and coprecipitation

In order to investigate the efficiency of sulfate green rust (GR2) to remove Ni from solution, GR2 samples were synthesized under controlled laboratory conditions. Some GR2 samples were synthesized from Fe(II) and Fe(III) sulfate salts by precipitation. Other samples were prepared by coprecipitation, of Ni(II), Fe(II) and Fe(III) sulfate salts, i.e., in the presence of Ni. In another sample, Ni(II) sulfate salt was added to pre-formed GR2. After an initial X-ray diffraction (XRD) characterization all samples were exposed to ambient air in order to understand the role of Ni in the transformation of the GR2 samples. XRD was repeated after 45 days. The results showed that Nious GR2 prepared by coprecipitation is isomorphous to Ni-free GR2, i.e. Ni is incorporated into the crystalline structure. Fe(II) was not replaced by Ni(II) in the crystalline structure of GR2 formed prior to exposure to solution-phase Ni. This suggests Ni was adsorbed to the GR2 surface. Sulfate green rust is more efficient in removing Ni from the environment by coprecipitation.

Production in second cycle of physic nut irrigated with saline water in greenhouse

The objective of this work was to evaluate the effects of the irrigation with saline water on production of physic nut (Jatropha curcas L.) after pruning (396 days after sowing). Between May 2008 and January 2009, the experiment was carried out in a greenhouse. The plants were grown in drainage lysimeters (200L) containing 230 kg of non-saline and non-sodic soil properly fertilized, classified as Gray Argisoil Eutrophic. Treatments consisted of five levels of electrical conductivity of the irrigation water - ECw (0.6; 1.2; 1.8; 2.4 and 3.0 dS m-1, at 25 oC). All the plants were pruned at 80 cm height. At 240 days after pruning the variables: number of bunches, weight of main of scab, seeds and fruits, weights of seed and fruit, number of fruits and oil content were evaluated. Plants irrigated with water of 3.0 dS m-1were significantly affected with the following reductions: 93% in number of bunches, 97% in the variables weight of scab, of seeds and fruits, and number of fruits; 67% in fruit weight, and 49% in seed weight. Oil content of plants irrigated with water of 3.00 dS m-1 had reduction of 30.56%.

Crescimento de cultivares de girassol ornamental influenciado por doses de silício no solo

Few experimental studies have been carried out to analyze growth of the ornamental sunflower under protected environment conditions. Thus, the aim of this study was to evaluate effects of different silicon doses on the growth of two cultivars of ornamental sunflower. The experiment was conducted in a greenhouse, from September to December 2010. The treatments were arranged in a completely randomized design with three replications in a 5 x 2 factorial scheme, referring to doses 0; 2; 4; 6 and 8 g of Si per pot and cultivars of ornamental sunflower Jardim Amarelo Alto and Sol Vermelho. Each experimental unit consisted of a plastic pot with a capacity of 10 L, with 5.33 L of soil. All experimental units were fertilized with N:P2O5:K2O in a dose of 60-80-80 kg ha-1. Doses of silicon significantly increased the external capitulum diameter and the total opening of flower bud (days) sunflower plant. The cultivar Sol Vermelho showed better response to the application of silicon compared to Jardim Amarelo Alto.

Esterco bovino líquido em luvissolo sódico: Resposta biométrica e produtiva do maracujazeiro amarelo

The objective of the present study was to evaluate the effect of liquid bovine biofertilizer on the biometry and the dry matter production of yellow passion fruit seedlings grown on sodic Luvissol. The experiment was performed in the Department of Soil and Rural Agricultural Engineering of the Center of Agricultural Sciences (CCA), Federal University of Paraiba (UFPB), from August to October 2008. The experimental design was that of randomized blocks in split plots, where the plots were the levels of liquid biofertilizer at 0, 25, 50, 75 and 100% by volume of 10% of the total substratum volume (250 mL), the subplots were the five plant evaluation periods (45, 60, 75, 90 and 105 days after the sowing); the experiment was performed in quadruplicate. The application of biofertilizer was made 30 days before sowing, followed by a washing of the soil (two days after of biofertilizer application); a second application of the biofertilizer was made 48 hours before sowing, followed by a soil washing similar to that of the first application. Non-saline water was used for irrigation, adding the water equivalent to the evapotranspiration rate per 24 hours, based on weighing the pots. The increased level of organic matter input provided greater plant height and stem diameter, as well as greater leaf number, foliar area and total dry matter, surpassing the control by 134.78; 114.72; 127.35; 416.54 and 107.97%, respectively.