1000 resultados para Jatropha gossypiifolia L


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The physic nut can be propagated asexually or sexually. Using cuttings have been earlier yield and more fidelity characteristics of the parent plant. However, there is less initial vegetative growth. The seeds from the plants have increased genetic variability, are more vigorous and begin production later. To get quality changes, the substrate is an important factor. With that the objective was to taste pre-germinated treatments and different substrate on seeds emergence and quality physic nut seedlings. The experimental design was completely randomized, in factorial scheme 6 x 3 (pre-germinated treatments x substrate), 18 treatments and 4 repetition, 8 seeds to each repetition. It was evaluated six pre-germination treatments: T1: witness (without treatments); T2: water immersion for 12 hours; T3: water immersion for 24 hours; T4: mechanical scarification; T5: mechanical scarification + water immersion for 12 hours; T6: mechanical scarification + water immersion for 24 hours, using as substrate: commercial, expanded vermiculite and sand washed. The mechanical scarification was realized opposite the micropyle using sandpaper n. 60. After the pre-germination treatments, the seeds were emergence in plastic cups (200mL) with substrates. We evaluated the characteristics: percentage, beginning and emergence speed index, mean length of plant, diameter of plant stem, SPAD index, fresh and dry shoot and root. The results showed that in seeds of Jatropha do not need pre-germinative treatments; and the use of commercial substrate showed seedling development.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Between 2004 and 2007, NGOs, community based organisations and private investors promoted jatropha in Kenya with the aim of generating additional income and producing biofuel for rural development. By 2008 it became gradually evident that jatropha plantations (both mono- and intercropping) are uneconomical and risky due to competition for land and labour with food crops. Cultivation of jatropha hedges was found to have better chances of economic success and to present only little risks for the adopting farmers. Still, after 2008 a number of farmers went on adopting jatropha in plots rather than as hedges. It is hypothesised that lack of awareness about the low economic prospects of jatropha plantations was the main reason for continued adoption, and that smallholder farmers with higher resource endowments mainly ventured into its cultivation. In this study we provide an empirical basis for understanding the role of households' capital assets in taking up new livelihood strategies by smallholder farmers in three rural districts in Kenya. For that purpose, we assess the motivation and enabling factors that led to the adoption of jatropha as a new livelihood strategy, as well as the context in which promotion and adoption took place. A household survey was conducted in 2010, using a structured questionnaire, to collect information on household characteristics and capital asset endowment. Data were analysed using descriptive statistics and non-parametric statistical tests. We established that access to additional income and own energy supply were the main motivation for adoption of jatropha, and that financial capital assets do not necessarily have a positive influence on adoption as hypothesised. Further, we found that the main challenges that adopting farmers faced were lack of access to information on good management practices and lack of a reliable market. We conclude that continued adoption of on-farm jatropha after 2008 is a result of lacking awareness about the low economic value of this production type. We recommend abandoning on-farm production of jatropha until improved seed material and locally adapted agronomic knowledge about jatropha cultivation becomes available and its production becomes economically competitive.

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Biofuel plants such as Jatropha curcas L. have potential to support the livelihoods of rural communities and contribute to sustainable rural development in Africa, if risks and uncertainties are minimized. Yet, recent papers have warned of the risk of biological invasions in such tropical regions as a consequence of the introduction of exotic biofuel crops. We investigated the seed dispersal risk and invasiveness potential of both J. curcas monoculture plantations and live fences into adjacent cultivated and uncultivated land use systems in Sissili province, Burkina Faso. Invasiveness potential was assessed through (i) detecting evidence of natural regeneration in perimeters around J. curcas plantations and live fences, (ii) assessing seed dispersal mechanisms, and (iii) assessing seedling establishment potential through in situ direct seed sowing. Spontaneous regeneration around the plantation perimeters of the three sites was very low. Individual seedling density around J. curcas live fences was less than 0.01 m−2 in all sites. Seventy percent of the seedlings were found close to the live fence and most of them derived from the same year (96 %), which indicates low seed-bank longevity and seedling survival. J. curcas can be dispersed by small mammals and arthropods, particularly rodents and ants. In some sites, such as in Onliassan, high secondary seed dispersal by animals (up to 98 %) was recorded. There were highly significant differences in germination rates between seeds at the soil surface (11 %) and those buried artificially at 1–2-cm depth (64 %). In conclusion, we failed to find convincing evidence of the spreading of J. curcas or any significant impact on the surrounding environment.

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La especie Jatropha curcas L., comúnmente conocida en México como piñoncillo, es una planta productora de aceite que ha recibido gran atención en recientes años al utilizarse como fuente de energía por su gran potencial para la elaboración de biodiesel. Sin embargo, su introducción mundial como especie bioenergética se ha dado con diferentes grados de éxito debido al heterogéneo rendimiento de semillas y contenido de aceite como consecuencia de su amplia variabilidad genética. Esto ha impulsado la selección de genotipos elite, los cuales deben contar con un protocolo de propagación clonal por medio del cultivo de tejidos vegetales para acelerar el desarrollo de cultivares. La mayoría de los estudios morfogénicos se han hecho a partir de explantes de genotipos procedentes de la India, de modo que es necesario el estudio de los factores que afectan la morfogénesis en genotipos mexicanos, debido a la amplia variación genética. Los objetivos del presente estudio fueron: i) evaluar la expresión morfogénica de explantes bajo diferentes niveles de reguladores de crecimiento (thidiazurón, 6- bencilaminopurina y ácido indol-3-butírico) en dos medios de cultivo (Yasuda y MS), ii) estudiar la respuesta de explantes por efecto de 500 mg L-1 de polivinilpirrolidona (PVP) en la etapa de establecimiento in vitro de dos genotipos de Jatropha curcas (INI-3 e INI-6), y iii) determinar el comportamiento de la enzima polifenol oxidasa (PPO) en explantes de hoja y peciolo de dos genotipos de Jatropha curcas (INI-3 e INI-6) bajo la aplicación de hipoclorito de sodio (NaClO) al 3.24 % como agente desinfectante. En la etapa de establecimiento in vitro se evaluó el efecto del PVP en explantes de hoja y peciolo de los genotipos INI-3 e INI-6 bajo un diseño completamente al azar (DCA) con un arreglo factorial 2x2 con 90 repeticiones por tratamiento y un explante por unidad experimental, donde en el factor A fueron los genotipos (INI-3 e INI-6) y el factor B las dosis de PVP (control y 500 mg L-1). Las variables evaluadas en una prueba de ji-cuadrada fueron: viabilidad y presencia de callo, mientras que el peso de callo se evaluó por un análisis de varianza. En la etapa de inducción se analizaron los medios de cultivo Yasuda y MS más la interacción con diferentes dosis de thidiazurón (1.5 y 3.0 mg L−1), 6-bencilaminopurina (1.5 y 3.0 mg L−1), y (AIB) ácido indol-3-butírico (0.0, 0.5 y 1.0 mg L−1) en explantes de peciolo del genotipo INI-6, bajo un DCA con arreglo factorial 2x2x2x3 con tres repeticiones, compuestas de dos explantes por unidad experimental, donde la variable presencia de callo fue evaluada en un análisis de regresión logística. La determinación de la actividad de PPO se realizó bajo un DCA con arreglo factorial 2X2X2 con tres repeticiones, donde en el factor A fueron las dosis de NaClO (control y 3.24 %), el factor B los tipos de explantes (hoja y peciolo) y el factor C los genotipos (INI-6 e INI-3). Los resultados del establecimiento in vitro mostraron que únicamente el explante de peciolo fue viable al cultivo, revelando que los genotipos de estudio no presentan asociación con las frecuencias de explantes viables de acuerdo con las pruebas de ji-cuadrada. En esta misma etapa se encontró que la viabilidad de explantes varió según la posición del peciolo con base en el ápice terminal, donde los explantes del segundo nudo presentaron la mayor viabilidad con base en una prueba de jicuadrada. Además, la adición de PVP aumentó la viabilidad de explantes de peciolo e indujo la proliferación de callo con una diferencia significativa en la producción de callo fresco entre genotipos según el análisis de varianza. En la etapa de inducción se encontró que los factores AIB y TDZ además de las interacciones “TDZ*AIB” y “TDZ*BAP*AIB” están relacionadas significativamente con la presencia de callo y ningún tratamiento indujo el desarrollo de brotes a las ocho semana de cultivo in vitro. En la determinación de la actividad de PPO, se encontró que estadísticamente la aplicación de NaClO al 3.24 % causa el aumento en la actividad de PPO, además se descubrió diferencias estadísticas entre explantes y genotipos de estudio.

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2016

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Introduction Jatropha gossypifolia has been used quite extensively by traditional medicine for the treatment of several diseases in South America and Africa. This medicinal plant has therapeutic potential as a phytomedicine and therefore the establishment of innovative analytical methods to characterise their active components is crucial to the future development of a quality product. Objective To enhance the chromatographic resolution of HPLC-UV-diode-array detector (DAD) experiments applying chemometric tools. Methods Crude leave extracts from J. gossypifolia were analysed by HPLC-DAD. A chromatographic band deconvolution method was designed and applied using interval multivariate curve resolution by alternating least squares (MCR-ALS). Results The MCR-ALS method allowed the deconvolution from up to 117% more bands, compared with the original HPLC-DAD experiments, even in regions where the UV spectra showed high similarity. The method assisted in the dereplication of three C-glycosylflavones isomers: vitexin/isovitexin, orientin/homorientin and schaftoside/isoschaftoside. Conclusion The MCR-ALS method is shown to be a powerful tool to solve problems of chromatographic band overlapping from complex mixtures such as natural crude samples. Copyright © 2013 John Wiley & Sons, Ltd. Extracts from J. gossypifolia were analyzed by HPLC-DAD and, dereplicated applying MCR-ALS. The method assisted in the detection of three C-glycosylflavones isomers: vitexin/isovitexin, orientin/homorientin and schaftoside/isoschaftoside. The application of MCR-ALS allowed solving problems of chromatographic band overlapping from complex mixtures such as natural crude samples. Copyright © 2013 John Wiley & Sons, Ltd.

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Pós-graduação em Biologia Animal - IBILCE

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Pós-graduação em Agronomia (Genética e Melhoramento de Plantas) - FCAV

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Given the necessity of developing jatropha cultivation equipment, this work adjusted different mathematical models to experimental data obtained from the drying of jatropha seeds submitted to different drying conditions and selected the best model to describe the drying process. The experiment was carried out at the Federal Institute of Goiás - Rio Verde Campus. Seeds with initial moisture content of approximately 0.50 (kg water/kg dry matter) were dried in a forced air-ventilated oven, at temperatures of 45, 60, 75, 90 and 105°C to moisture content of 0.10 ± 0.005 (kg water/kg dry matter). The experimental data were adjusted to 11 mathematical models to represent the drying process of agricultural products. The models were compared using the coefficient of determination, chi-square test, relative mean error, estimated mean error and residual distribution. It was found that the increase in the air temperature caused a reduction in the drying time of seeds. The models Midilli and Two Terms were suitable to represent the drying process of Jatropha seeds and between them the use of the Midili model is recommended due to its greater simplicity.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do Grau de Mestre em Energia e Bioenergia

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A systematic evaluation of agricultural factors affecting the adaptation of the tropical oil plant Jatropha curcas L. to the semi-arid subtropical climate in Northeastern Mexico has been conducted. The factors studied include plant density and topology, as well as fungi and virus abundances. A multiple regression analysis shows that total fruit production can be well predicted by the area per plant and the total presence of fungi. Four common herbicides and a mechanical weed control measure were established at a dedicated test array and their impact on plant productivity was assessed.