• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 17
  • 15
  • 10
  • 7
  • 1
  • Tagged with
  • 62
  • 20
  • 11
  • 9
  • 8
  • 8
  • 7
  • 7
  • 7
  • 7
  • 7
  • 6
  • 6
  • 6
  • 6
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Utilização de feno de erva sal (Atriplex nummularia Lind) e farelo de milho em substituição à palma forrageira (Opuntia fícus-indica Mil) em dieta para ovinos

RIBEIRO, Valéria Louro 06 November 2009 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-05-18T14:18:29Z No. of bitstreams: 1 Valeria Louro Ribeiro.pdf: 828153 bytes, checksum: 81b9fbfef0de4f350a8ed935cdf1f098 (MD5) / Made available in DSpace on 2017-05-18T14:18:29Z (GMT). No. of bitstreams: 1 Valeria Louro Ribeiro.pdf: 828153 bytes, checksum: 81b9fbfef0de4f350a8ed935cdf1f098 (MD5) Previous issue date: 2009-11-06 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This work aimed to evaluate the effects of replacing the spineless cactus (Opuntia ficus-indica Mill) by saltbush hay (Atriplex nummularia Lind.) and corn bran on feed intake, apparent digestibility of the diet, eating behavior and rumination parameters of sheep. The levels of replacement were of 0,0; 15,3; 35,3; 62,9 and 100 %.Five adult sheep were used, weighing 60kg and canulla inserted in the rumen. The sheep were assigned to five dietary treatments in a Latin square 5 x 5 (5 diets and 5 periods), housed in individual stalls. The intake of dry matter,water and salt were obtained by the difference between the food presented to it and the surpluses. To estimate fecal production we used chromium oxide in two daily 10g doses, applied via the rumen cannulla. The behavioral observations were conducted in the seventh day of adaptation of the experimental diet in intervals of five minutes during 24hr. The samples for determining the rumination parameters were collected 0 and 1, 2, 3, 4, 5, 6,7, 8, 9, 10, and 11 hours after feeding the animals. The intake of dry matter and nutrients, written in g/day, percentage of live weight (%LW) and grams per unit ofmetabolic weight (g/LW0,75), were influenced significantly (P<0,05) for the replacement levels, the largest intake being in the 35,3% and the 62,9% levels. The coefficients of apparent digestibility of dry matter (DCDM) and organic matter (DCOM) were not affected by the replacement. However the coefficient of digestibility of the fiber in neutral detergent (NDF) decreased. The water intake suffered significant influence (P<0,05), with averages of 4549; 4296; 4327, 2907 and 153 mL/day for water through diet. Salt intake was not affected (P>0,05). The times of feeding, rumination and total mastication had quadratic behavior, showing the respective maximum points of 61,39;41,32 and 46,34 %. The concentrations of ammonia, salt and volatile fat acids (VFA), pH and ruminal temperature were influenced significantly (P<0,05) by the increase in the substitution level. The concentration of ammonia nitrogen featured averages of 10,26 and 39,29 mL/100mL for the respective levels 0,0% and 100% of substitution. The largest average for pH was obtained for the level of 100% of substitution with average of 6,06. We can conclude that the substitution of the spineless cactus influences the intake and digestibility of the diet, besides modifying the pattern of the eatingbehavior and the rumination parameters of sheep. / Este trabalho teve por objetivo avaliar os efeitos da substituição da palma forrageira (Opuntia ficus-indica, Mill) por feno de erva sal (Atriplex nummularia Lind.) e farelo de milho sobre o consumo e digestibilidade aparente da dieta, comportamento ingestivo e parâmetros ruminais de ovinos. Os níveis de substituição da palma por feno de atriplex e farelo de milho foram: 0,0; 15,3; 35,3; 62,9 e 100 %. Foram utilizados cinco carneiros adultos, fistulados no rúmen, com peso vivo médio de 65 ± 2 kg. Os animais foram alojados em baias individuais, distribuídos em um delineamento quadrado latino 5 x 5 (5 dietas x 5 períodos). Os consumos de matéria seca, água e sal foram obtidos pela diferença entre o ofertado e as sobras. Para estimativa da produção fecal foi utilizado o óxido crômico, fornecido em duas doses diárias de 10 g, via fístula ruminal. As observações comportamentais foram realizadas em intervalos de cincominutos durante 24h. As amostras para determinação dos parâmetros ruminais foram tomadas a 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, e 11 horas após alimentação dos animais. Os consumos de matéria seca e dos nutrientes expressos em g/dia, percentagem de peso vivo (%PV) e gramas por unidade de peso metabólico (g/PV0,75) foram influenciados significativamente (P<0,05) pelos níveis de substituição com os maiores consumos entre os níveis de 35,3% e 62,9%. Os coeficientes de digestibilidade aparente da matéria seca (CDMS) e matéria orgânica (CDMO) não sofreram efeito da substituição, entretanto, o coeficiente de digestibilidade da fibra em detergente neutro (FDN) decresceu. O consumo de água sofreu influência significativa (P<0,05), com médias de 4549; 4296; 4327, 2907 e 153 mL/dia para água via dieta, já o consumo de sal não foi afetado (P>0,05). Os tempos de alimentação, ruminação e mastigação total tiveram comportamento quadrático, apresentando os respectivos pontos de máxima 61,39%; 41,32% e 46,34 %. As concentrações de nitrogênio amoniacal, sal e ácidos graxos voláteis (AGV), pH e temperatura ruminal foram influenciados significativamente (P<0,05) pelo aumentono nível de substituição. A concentração de amônia apresentou médias de 10,26 e 39,29 mg /100mL para os respectivos níveis 0,0% e 100 % de substituição. A maior média para pH foi obtida para o nível de 100% de substituiçãocom média de 6,06. Pode-se concluir que a substituição da palma influencia os consumos e digestibilidade da dieta, além de modificar o padrão do comportamento ingestivo e os parâmetros ruminais de ovinos.
52

Efectos in vitro de mutantes de trichoderma spp. en el control de Rhizoctonia solani (Kühn) y Phytophthora nicotianae (Breda de Haan)

Peña Gómez, Carolina Anahí January 2006 (has links)
No description available.
53

Whole-Genome Assembly of Atriplex hortensis L. Using OxfordNanopore Technology with Chromatin-Contact Mapping

Hunt, Spencer Philip 01 July 2019 (has links)
Atriplex hortensis (2n = 2x = 18, 1C genome size ~1.1 gigabases), also known as garden orach, is a highly nutritious, broadleaf annual of the Amaranthaceae-Chenopodiaceae family that has spread from its native Eurasia to other temperate and subtropical environments worldwide. Atriplex is a highly complex and polyphyletic genus of generally halophytic and/or xerophytic plants, some of which have been used as food sources for humans and animals alike. Although there is some literature describing the taxonomy and ecology of orach, there is a lack of genetic and genomic data that would otherwise help elucidate the genetic variation, phylogenetic position, and future potential of this species. Here, we report the assembly of the first highquality, chromosome-scale reference genome for orach cv. ‘Golden’. Sequence data was produced using Oxford Nanopore’s MinION sequencing technology in conjunction with Illumina short-reads and chromatin-contact mapping. Genome assembly was accomplished using the high-noise, single-molecule sequencing assembler, Canu. The genome is enriched for highly repetitive DNA (68%). The Canu assembly combined with the Hi-C chromatin-proximity data yielded a final assembly containing 1,325 scaffolds with a contig N50 of 98.9 Mb and with 94.7% of the assembly represented in the nine largest, chromosome-scale scaffolds. Sixty-eight percent of the genome was classified as highly repetitive DNA, with the most common repetitive elements being Gypsy and Copia-like LTRs. The annotation was completed using MAKER which identified 31,010 gene models and 2,555 tRNA genes. Completeness of the genome was assessed using the Benchmarking Universal Single Copy Orthologs (BUSCO) platform, which quantifies functional gene content using a large core set of highly conserved orthologous genes (COGs). Of the 1,375 plant-specific COGs in the Embryophyta database, 1,330 (96.7%) were identified in the Atriplex assembly. We also report the results of a resequencing panel consisting of 21 accessions which illustrates a high degree of genetic similarity among cultivars and wild material from various locations in North America and Europe. These genome resources provide vital information to better understand orach and facilitate future study and comparison.
54

Absorción de agua y nutrientes y respuesta fisiológica de plantas halofitas y glicofitas bajo condiciones de estrés salino

Agudelo Sánchez, Agatha 29 November 2021 (has links)
Tesis por compendio / [ES] El incremento en la concentración de sales en suelos y agua es una de las problemáticas que más amenazan a la humanidad por su efecto directo sobre la productividad de las cosechas. En líneas generales la pregunta a la que queremos contribuir es ¿cómo enfrentarnos a una situación de salinización en un contexto de cambio climático y crecimiento demográfico? Más concretamente estudiamos la problemática en el sureste español desde un enfoque en que los resultados puedan ser explotados en el corto y medio plazo por el sector empresarial. La Región de Murcia es una de las principales zonas productoras del sureste español donde además existen graves problemas de salinización. En la presente tesis doctoral se propone utilizar aguas salinas para riego e investigar las implicaciones de ello a nivel de absorción de agua y nutrientes, estudiando también los cambios fisiológicos en la planta para obtener aplicaciones que permitan el crecimiento económico. En este sentido se abordan dos estrategias: por un lado, el estudio de plantas halofitas, y por otro, la bioestimulación en plantas glicofitas. La mayoría de los cultivos productivos son plantas glicofitas, ven afectadas sus producciones cuando hay elevadas concentraciones de sal en el medio de cultivo. Por el contrario, las plantas halofitas han desarrollado diferentes mecanismos para resistir los efectos negativos de la salinidad. Es por ello que la explotación directa de halofitas se ha identificado como una salida económica para las zonas afectadas. Otra forma de mitigación de los efectos del cambio climático es el desarrollo de la bioestimulación para incrementar la resistencia a estreses o para incrementar la concentración de compuestos bioactivos en los alimentos. Para los estudios realizados, se seleccionaron 6 especies vegetales que fuesen representativas de los diferentes comportamientos frente a la salinidad, que fuesen propias de la localización seleccionada (Región de Murcia) y de interés para la empresa promotora del proyecto de investigación (Sakata Seed Ibérica). Las especies estudiadas fueron: Brassica oleracea L., Brassica rapa L., Cakile maritima, Salicornia fruticosa y Atriplex halimus. El primer objetivo se centró en el análisis de los efectos de la salinidad sobre las especies objeto de estudio. Más concretamente intentando identificar rasgos que pudiesen servir para discriminar entre especies y/o cultivares las mejores respuestas a la salinidad. Por un lado, las interrelaciones entre distintos rasgos fisiológicos en respuesta a la salinidad se analizaron estadísticamente mediante un Discriminant Canonical Analysis (DCA), en el que se observó una relación entre el crecimiento y la suculencia de las hojas como medida de adaptación a la salinidad. Patrones como la acumulación de iones, el contenido en proteínas y ácidos grasos insaturados en respuesta a la salinidad pueden emplearse para discriminar entre distintas respuestas al estrés salino. Por otro lado, se estudió el efecto de la salinidad sobre la concentración y el perfil de glucosinolatos de distintos cultivares de brócoli (Brassica oleracea L.) en distintos periodos productivos. También se observó el efecto estimulador de los estreses como la temperatura y la salinidad sobre el perfil de glucosinolatos y la posibilidad de inducir complejos de glucosinolatos con fenólicos que no habían sido descritos previamente en Brassicales. El segundo objetivo se centró en la búsqueda de formas de explotación económica de las distintas respuestas fisiológicas. Por un lado, se desarrolló una metodología que permitió incrementar el contenido en glucosinolatos de las plantas de brócoli, sin que se viese en detrimento ni la producción ni los parámetros organolépticos del órgano comercial, lo cual fue posible mediante la aplicación de metil jasmonato y un polieter polisiloxano de forma foliar. Por otro lado, en las especies halofitas se analizó su aptitud par / [CA] L'augment de la concentració de sals en sòls i aigua és un dels problemes que més amenacen la humanitat pel seu efecte directe sobre la productivitat dels cultius. En termes generals, la qüestió a la qual volem contribuir és: com afrontar una situació de salinització en un context de canvi climàtic i creixement de la població? Més concretament, hem estudiat els problemes del sud-est d'Espanya des d'un enfocament en què els resultats poden ser explotats a curt i mitjà termini pel sector empresarial. La Regió de Múrcia és una de les principals zones productores del sud-est d'Espanya on també hi ha greus problemes de salinització. En aquesta tesi s'utilitzen aigües salines per al reg i s'investiguen les implicacions que això comporta a nivell d'absorció d'aigua i nutrients, estudiant també els canvis fisiològics en la planta per obtenir aplicacions que permetin el creixement econòmic. En aquest sentit s'aborden dues estratègies: d'una banda, l'estudi de les plantes d'halòfites i, de l'altra, la bioestimulació en plantes glicòfítes. La majoria dels cultius productius són plantes glicòfites, la seva produccions es veu afectada quan hi ha altes concentracions de sal en el medi de creiximent. Per contra, les plantes halófites han desenvolupat diferents mecanismes per resistir els efectes negatius de la salinitat. És per això que l'explotació directa d'halòfits s'ha identificat com una sortida econòmica per a les zones afectades. Una altra forma de mitigació dels efectes del canvi climàtic és el desenvolupament de bioestimulació per augmentar la resistència a estrès o augmentar la concentració de compostos bioactius en els aliments. Per als estudis realitzats en aquesta tesi doctoral es van seleccionar 6 espècies vegetals representatives dels diferents comportaments contra la salinitat, típics de la ubicació seleccionada (Regió de Múrcia) i d'interès per a l'empresa promotora del projecte de recerca (Sakata Seed Ibérica). Les espècies estudiades van ser: Brassica oleracea L., Brassica rapa L., Cakile maritima, Salicornia fruticosa i Atriplex halimus. El primer objectiu es va centrar en l'anàlisi dels efectes de la salinitat sobre les espècies objecte d'estudi. Més específicament tractant d'identificar trets que podrien servir per discriminar entre espècies i/o cultivars amb les millors respostes a la salinitat. D'una banda, les interrelacions entre diferents trets fisiològics en resposta a la salinitat van ser analitzades estadísticament per una Anàlisi Canònica Discriminant (DCA), en la qual s'observava una relació entre el creixement i la suculència de les fulles com a mesura d'adaptació a la salinitat. Patrons com l'acumulació d'ions, el contingut de proteïnes i àcids grassos insaturats en resposta a la salinitat es poden utilitzar per discriminar entre diferents respostes a l'estrès salí. D'altra banda, s'ha estudiat l'efecte de la salinitat en la concentració i perfil de glucosinolats de diferents cultius de bròquil (Brassica oleracea L.) en diferents períodes de producció. També vam observar l'efecte estimulant d'estrès com la temperatura i la salinitat en el perfil dels glucosinolats i la possibilitat d'induir complexos glucosinolatats amb fenòlics que no s'havien descrit prèviament en brassicales. El segon objectiu es va centrar en la recerca de formes d'explotació econòmica de les diferents respostes fisiològiques. D'una banda, es va desenvolupar una metodologia que permetia augmentar el contingut de glucosinolat de plantes de bròquil, sense perjudici ni de la producció ni dels paràmetres organolèptics de l'òrgancomercial, que va ser possible mitjançant l'aplicació de jasmonat de metil i un polieter de polisiloxà de forma foliar. D'altra banda, per a les espècies d'halòfits, es va realitzar una anàlisi per determinar la seva idoneïtat per a possibles usos tant culinaris com industrials. / [EN] The increase in the concentration of salts in soils and water is one of the problems that most threatens humanity due to its direct effect on crop productivity. In general terms, the question we want to contribute to is how to deal with salinization in the context of climate change and population growth? More specifically, we study the problems in south-eastern Spain from an approach in which the results can be exploited in the short and medium-term by the business sector. The region of Murcia is one of the main producing areas in south-eastern Spain where there are also serious salinization problems for various reasons. In this doctoral thesis, it is proposed to use saline water for irrigation and to investigate the implications that this entails at the level of water and nutrient absorption, also studying the physiological changes in the plant to obtain applications that allow economic growth. In this sense, two strategies are approached: on the one hand, the study of halophytic plants, and on the other hand, biostimulation in glycophyte plants. Most of the productive crops are glycophyte plants, their productions are affected when there are high concentrations of salt in the culture medium. On the contrary, halophyte plants have developed different mechanisms to resist the negative effects of salinity. That is why the direct exploitation of halophytes have been identified as an economic outlet for the salt-affected areas. Another way of mitigating the effects of climate change is the development of biostimulation to increase resistance to stresses or to increase the concentration of bioactive compounds in food. For the studies carried out in this doctoral thesis, 6 plant species were selected that were representative of the different behaviours towards salinity, that were specific to the selected location (The region of Murcia), and of interest to the company promoting the research project (Sakata Seed Ibérica). The species studied were: Brassica oleracea L., Brassica rapa L., Cakile maritima, Salicornia fruticosa, and Atriplex halimus. The first objective of this thesis focused on the analysis of the effects of salinity on the species understudy. More specifically trying to identify traits that could serve to discriminate between species and/or cultivars that best respond to salinity. Moreover, the interrelationships between different physiological traits in response to the salinity were statistically analysed using a Discriminant Canonical Analysis (DCA), in which a relationship between growth and succulence of the leaves were observed as a measure of adaptation to salinity. Patterns such as ion accumulation, protein content, and unsaturated fatty acids in response to salinity can be used to discriminate between different responses to salt stress. On the other hand, the effect of salinity on the concentration and profile of glucosinolates of different cultivars of broccoli (Brassica oleracea L.) indifferent productive periods were also studied. The stimulating effect of stresses such as temperature and salinity on the glucosinolate profile and the possibility of inducing glucosinolates with phenolics complexes that had not been previously described in Brassicales were also observed. The second objective focused on the search for forms of economic exploitation of the different physiological responses. On the one hand, a methodology was developed that allowed increasing the glucosinolate content of broccoli plants, without affecting the production or any organoleptic parameter of the commercial organ. This was possible through the application of methyl jasmonate and a polyether polysiloxane in foliar form. On the other hand, for the halophyte species, an analysis was carried out to determine their aptitude for possible culinary and industrial uses. / This work was funded by the Spanish Ministerio de Ciencia, Innovación y Universidades (AGL2016-80247-C2-1-R and RTC-2015-3536-2). / Agudelo Sánchez, A. (2021). Absorción de agua y nutrientes y respuesta fisiológica de plantas halofitas y glicofitas bajo condiciones de estrés salino [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/177647 / Compendio
55

Dinâmica da água e dos nutrientes no sistema de produção integrado gerado pela dessalinização da água de poço do semiárido brasileiro / Dynamics of water and nutrients in the integrated production system generated by desalination of ground water from Brazilian semiarid

Vasconcellos, Eduardo Ballespi de Castro 01 July 2011 (has links)
Foram realizadas análises isotópicas, físicas e químicas na água, no solo e nas plantas do Sistema de Produção Integrado Utilizando Efluentes de Dessalinização, criado pela Embrapa Semiárido, como uma alternativa para a reutilização desses efluentes na produção de alimentos e diminuição do impacto ambiental causado pelo descarte incorreto deste rejeito. O sistema avaliado se localiza no Campo Experimental da Caatinga, na Embrapa Semiárido (Petrolina-PE). Os resultados encontrados quanto à ciclagem dos nutrientes indicaram a ocorrência de uma contínua adição dos cátions Ca+2, Mg+2 , K+ e Na+ no solo durante o experimento, de 199 kg ha-1, 88 kg ha-1, 51 kg ha-1 e 142 kg ha-1, respectivamente. A eficiência de retirada do Ca+2, Mg+2 e Na+ pela Atriplex nummularia foi de 12,1, 4,3 e 23,9%, respectivamente; Ocorreu uma elevada perda de nitrogênio no sistema causado pelo processo de denitrificação, que diminuiu a concentração de nitrogênio em 72% do inicio ao final do sistema, levando este nutriente em quantidades insuficientes para a área agrícola. Estes resultados serão utilizados para indicar caminhos de melhorias no sistema. Ainda, quanto aos resultados isotópicos, foi possível concluir que: a água sofre um fracionamento durante o processo de osmose reversa na ordem de 1,87 para o 18O e 10,3 para o 2H; A água do poço é formada por uma mistura de águas recentes e paleoáguas; A relação 18O vs 2H; possui um coeficiente angular de 4,1, indicando elevada evaporação neste elemento; O solo avaliado possui uma média isotópica de -24 de 13C no solo de caatinga e -20 de 13C na área experimental, indicando uma troca da matéria orgânica desta área por material proveniente da Atriplex, que teve uma razão isotópica média de -13,7 .de 13C. / Isotopic, physical and chemical analysis were performed in water, soil and plants of the \" Integrated Production System Using Wastewater Desalination \", created Embrapa Semiarid, as an alternative to reuse of wastewater for food production and reducing the environmental impact caused by the incorrect disposal of the reject. The evaluated system is located in the Experimental Área Caatinga at Embrapa Semi-Arid (Petrolina-PE). The findings about the cycling of nutrients indicated the occurrence of a continuous addition of Ca+2, Mg+2, K+ and Na+ in the soil during the experiment of, 199 kg ha-1, 88 kg ha-1, 51 kg ha-1 and 142 kg ha-1, respectively. The efficiency of removal of Ca+2, Mg+2 and Na+ by Atriplex nummularia was 12,1, 4,3 and 23,9% respectively; Was observed high loss of nitrogen in the system caused by denitrification process, which decreased the concentration of nitrogen by 72% from beginning to end system, taking this nutrient in insufficient quantities to agricultural area. These results will be used for indicate ways to improve the system. Also, with the isotopic results was concluded that: water undergoes fractionation during the process of reverse osmosis the order of 1,87 to 18O and 10,3 for 2H; The well water is formed by a mixture of recent water and paleoáguas; The relationship 18O vs 2H; has a slope of 4,1, indicating high evaporation of this element; The soil has an average rated -24 in isotopic 13C in savanna soi and -20 of 13C in the experimental area, indicating an exchange of matter of this area of organic material from Atriplex, which had an average isotopic ratio of -13,7 . of 13C.
56

Leaf-litter and microsite on seedling recruitment in an alley-planted E. sargentii and Atriplex spp. saline agricultural system

Farrell, Claire January 2008 (has links)
[Truncated abstract] In order to assess the sustainability of mixed plantings on saline land, this thesis examined the importance of leaf-litter trapping and microsites on recruitment in a salt affected alley-belted (tree/shrub) agricultural system in Western Australia. Located in the low rainfall region (MAR <330 mm) of the wheatbelt, the 60 ha site consists of concentric rows of Eucalyptus sargentii trees with mounded (6 - 11 cm high) 10 -15 m inter-rows of Atriplex spp. Sustainability of this system and fulfilment of productive and ameliorative functions is dependant on successful recruitment (perennials). Although the present study site was conducted on farmland in a Mediterranean-type climate, low annual rainfall and spatial arrangement of perennial shrubs and trees, allow useful comparisons to be made with naturally occurring banded semi-arid systems and vice-versa. Of key interest were leaf-litter redistribution and trapping by tree and shrub rows and whether litter-cover/microsites facilitated/interfered with seedling recruitment (establishment, growth and survival). Litter from the tree row, redistributed by prevailing winds and rain, accumulated adjacent to saltbush seeding mounds, creating a mosaic of bare and littered areas across the site (total litter 10 t/ha over 22 months). Accumulated litter was hypothesized to differentially influence seasonal soil abiotic parameters (depending on litter-cover density) including; salinity, water availability, infiltration rates, water repellency and temperature. These abiotic conditions were also hypothesized to vary between tree and shrub microsites. Biotically, recruitment at this site was also hypothesized to be determined by interactions (positive and negative) between perennial components and understorey annuals/perennial seedlings. Accumulation of litter and resultant heterogeneity was influenced by shrub morphology, microtopography, wind direction and distance from litter source, with increased litter on the leeward sides of hemispherical Atriplex undulata shrubs and shrubs closest to tree rows. ... The importance of tree/shrub microsites varied seasonally, with no influence in winter due to moderate temperatures and increased water availability. In warmer months saltbush mid-row microsites were most favourable for seedling recruitment due to moderate litter-cover; reducing salinity, temperatures and increasing infiltration; and reduced root-competition/shading by the tree row. Tree microsites also directly inhibited seedling recruitment through increased salinities and water repellency. However, trees also indirectly facilitated recruitment in adjacent areas through provision of leaf-litter. As litter-trapping and recruitment patterns at this site mirror those found in semi-arid natural and artificial systems, the results of this study provide useful insights into creating appropriate mimics of low rainfall natural banded woodland and chenopod shrublands. Saltbush seeding mounds, shrub morphology and litter were key components for litter trapping and recruitment heterogeneity at this site. In this tree/shrub alley planting, where litter quantities directly influence vegetation cover densities, future saline plantings need to consider appropriate tree/shrub row spacings and orientation for efficient resource (seeds, litter and water) capture.
57

Dinâmica da água e dos nutrientes no sistema de produção integrado gerado pela dessalinização da água de poço do semiárido brasileiro / Dynamics of water and nutrients in the integrated production system generated by desalination of ground water from Brazilian semiarid

Eduardo Ballespi de Castro Vasconcellos 01 July 2011 (has links)
Foram realizadas análises isotópicas, físicas e químicas na água, no solo e nas plantas do Sistema de Produção Integrado Utilizando Efluentes de Dessalinização, criado pela Embrapa Semiárido, como uma alternativa para a reutilização desses efluentes na produção de alimentos e diminuição do impacto ambiental causado pelo descarte incorreto deste rejeito. O sistema avaliado se localiza no Campo Experimental da Caatinga, na Embrapa Semiárido (Petrolina-PE). Os resultados encontrados quanto à ciclagem dos nutrientes indicaram a ocorrência de uma contínua adição dos cátions Ca+2, Mg+2 , K+ e Na+ no solo durante o experimento, de 199 kg ha-1, 88 kg ha-1, 51 kg ha-1 e 142 kg ha-1, respectivamente. A eficiência de retirada do Ca+2, Mg+2 e Na+ pela Atriplex nummularia foi de 12,1, 4,3 e 23,9%, respectivamente; Ocorreu uma elevada perda de nitrogênio no sistema causado pelo processo de denitrificação, que diminuiu a concentração de nitrogênio em 72% do inicio ao final do sistema, levando este nutriente em quantidades insuficientes para a área agrícola. Estes resultados serão utilizados para indicar caminhos de melhorias no sistema. Ainda, quanto aos resultados isotópicos, foi possível concluir que: a água sofre um fracionamento durante o processo de osmose reversa na ordem de 1,87 para o 18O e 10,3 para o 2H; A água do poço é formada por uma mistura de águas recentes e paleoáguas; A relação 18O vs 2H; possui um coeficiente angular de 4,1, indicando elevada evaporação neste elemento; O solo avaliado possui uma média isotópica de -24 de 13C no solo de caatinga e -20 de 13C na área experimental, indicando uma troca da matéria orgânica desta área por material proveniente da Atriplex, que teve uma razão isotópica média de -13,7 .de 13C. / Isotopic, physical and chemical analysis were performed in water, soil and plants of the \" Integrated Production System Using Wastewater Desalination \", created Embrapa Semiarid, as an alternative to reuse of wastewater for food production and reducing the environmental impact caused by the incorrect disposal of the reject. The evaluated system is located in the Experimental Área Caatinga at Embrapa Semi-Arid (Petrolina-PE). The findings about the cycling of nutrients indicated the occurrence of a continuous addition of Ca+2, Mg+2, K+ and Na+ in the soil during the experiment of, 199 kg ha-1, 88 kg ha-1, 51 kg ha-1 and 142 kg ha-1, respectively. The efficiency of removal of Ca+2, Mg+2 and Na+ by Atriplex nummularia was 12,1, 4,3 and 23,9% respectively; Was observed high loss of nitrogen in the system caused by denitrification process, which decreased the concentration of nitrogen by 72% from beginning to end system, taking this nutrient in insufficient quantities to agricultural area. These results will be used for indicate ways to improve the system. Also, with the isotopic results was concluded that: water undergoes fractionation during the process of reverse osmosis the order of 1,87 to 18O and 10,3 for 2H; The well water is formed by a mixture of recent water and paleoáguas; The relationship 18O vs 2H; has a slope of 4,1, indicating high evaporation of this element; The soil has an average rated -24 in isotopic 13C in savanna soi and -20 of 13C in the experimental area, indicating an exchange of matter of this area of organic material from Atriplex, which had an average isotopic ratio of -13,7 . of 13C.
58

Atividade biológica e bioprospecção de bactérias associadas à Atriplex nummularia em solos salino sódico no agreste de Pernambuco / Biological activity and characterization of bacteria associated with Atriplex nummularia in saline sodic in the Agreste of Pernambuco.

SANTOS, Karen Cristina Fialho dos 24 May 2010 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-08-04T13:10:09Z No. of bitstreams: 1 Karen Cristina Fialho dos Santos.pdf: 989764 bytes, checksum: 20831bbd6a6bf051ec590c5f66b24703 (MD5) / Made available in DSpace on 2016-08-04T13:10:09Z (GMT). No. of bitstreams: 1 Karen Cristina Fialho dos Santos.pdf: 989764 bytes, checksum: 20831bbd6a6bf051ec590c5f66b24703 (MD5) Previous issue date: 2010-05-24 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Soil salinity is a growing problem that has been developed in an uncontrolled manner throughout the world, having as causes: the release of salts from the source material, or excessive irrigation with water of poor quality and high evapotranspiration, which is not account is offset by the low annual rainfall, promoting the degradation of large areas. To the rehabilitation, the use of plants for phytoextraction of soil salts, such as Atriplex nummularia, has proved quite feasible. For species that can grow in extreme environments, such as the Atriplex, symbiotic associations with microorganisms adapted to this environment may contribute to its establishment and effectiveness in extracting salt. Thus, the purpose of this study is to evaluate the biological activity and the organisms in saline sodic soil in the presence or absence of Atriplex nummularia that may contribute to the development of the halophyte species. We studied microorganisms associated with environments with and without plants of A. nummularia deployed in a field experiment in Fluvic Neossoils saline sodic in the city of Pesqueira-PE. Two samples were taken, one in the dry season and another in the rainy season when the soil is completely saturated by water. Soil samples were analyzed for microbial activity and biological bioprospecting by isolating of the bacteria, which were chosen according to the different shapes and colors of the colonies, and also by testing for nitrogen fixation and production of IAA. The results of microbial activity showed that the distance from the root interfere in the general data of carbon and nitrogen of microbial biomass and basal respiration, and the highest values found near the roots of the plant, indicating that the presence of Atriplex tends to promote a increase in soil microbes and also that greater interaction with the roots in dry periods, promotes a benefit to the organisms found on site. The bacterial population studied in all the points collected in both periods was higher in the rhizoplane, reinforcing the strong association of these microorganisms, particularly bacteria with plants of Atriplex. The endophytic bacteria isolated from leaf and root tissues of plants of A. nummularia, even in smaller quantities in relation to population density, were able in two sampling in fix nitrogen and produce IAA in a satisfactory percentage, showing the importance of endophytic bacteria for the development of plants of the species because they may be contributing for the capacity of this plant biomass production in salt affected soils, thus increasing the potential of more species for phytoextraction. / A salinidade dos solos é um problema crescente e que vem se acentuando de forma descontrolada em todo o mundo, tendo como causas: a liberação de sais do material de origem, a irrigação em excesso ou com água de má qualidade e a elevada evapotranspiração, que não é compensada por conta das baixas taxas pluviométricas, promovendo a degradação de extensas áreas. Para a reabilitação, a utilização de plantas fitoextratoras de sais do solo, como a Atriplex nummularia, tem-se mostrado bastante viável. Para espécies que conseguem se desenvolver em ambientes extremos, como é o caso da Atriplex, associações simbióticas com microorganismos adaptados a este ambiente pode colaborar para seu estabelecimento e efetividade na extração de sais. Desta forma, o objetivo do presente trabalho é avaliar a atividade biológica e os organismos presentes em solo salino sódico na presença ou ausência de Atriplex nummularia que possam contribuir para o desenvolvimento desta espécie halófita. Foram estudados microorganismos associados a ambientes com e sem plantas de A. nummularia em experimento de campo implantado em Neossolo Flúvico salino sódico no Município de Pesqueira-PE. Duas amostragens foram realizadas, sendo uma no período seco e outra no período chuvoso, quando o solo se encontra completamente saturado por água. Nas amostras de solo foram realizadas análises da atividade microbiana e bioprospecção biológica através do isolamento das bactérias, que foram escolhidas de acordo com os diferentes formatos e colorações das colônias, e também através de testes para fixação de nitrogênio e produção de AIA. Os resultados da atividade microbiana demonstram que a distância da raiz interfere nos dados gerais de carbono e nitrogênio da biomassa microbiana, bem como da respiração basal, sendo os maiores valores encontrados próximos às raízes da planta, indicando que a presença da Atriplex tende a promover um aumento na microbiota do solo e também que uma maior interação com as raízes, em períodos de seca, promove um benefício aos microrganismos encontrados no local. A densidade populacional bacteriana estudada em todos os pontos nos dois períodos coletados foi maior no rizoplano, reforçando a forte associação destes microrganismos, em especial, bactérias com plantas de Atriplex. As bactérias endofíticas isoladas dos tecidos da folha e raiz das plantas de A. nummularia, mesmo em menor quantidade em relação à densidade populacional, foram capazes nas duas coletadas realizadas de fixar nitrogênio e produzir AIA em percentuais satisfatórios,mostrando a importância das bactérias endofíticas para o bom desenvolvimento das plantas da espécie pelo fato de que estas podem estar contribuindo para a capacidade de produção de biomassa desta planta em solos afetados por sais, aumentando desta forma a maior capacidade de fitoextração pela espécie.
59

Associação palma forrageira (Opuntia ficus indica Mill) feno de erva-sal (Atriplex nummularia L.) em dietas para cordeiros Santa Inês em confinamento

MATTOS, Carla Wanderley 06 March 2009 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-03-27T16:44:25Z No. of bitstreams: 1 Carla Wanderley Mattos.pdf: 1851496 bytes, checksum: d4830f03c5ec4f1d7bd2a148707d654a (MD5) / Made available in DSpace on 2017-03-27T16:44:25Z (GMT). No. of bitstreams: 1 Carla Wanderley Mattos.pdf: 1851496 bytes, checksum: d4830f03c5ec4f1d7bd2a148707d654a (MD5) Previous issue date: 2009-03-06 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The study was carried out to evaluate growth performance, nutrients intake, digestibility, and profitability of Santa Inês lambs fed with increasing levels of spineless cactus (Opuntia ficus-indica Mill). Forty lambs not castrate9, with initial live weight of 19.46±2.35 kg and four months of age were distributed in a randomized design with four diets and 10 replicates. The levels ofspineless cactus intluenced DMI (kg, %LW, and L WO.75), been observed quadratic effect with maximum values of 1.29 kg, 4.84% and 109.75 g/LW075, respectively, to 28.8, 21.4, and 23.6% of spineless cactus. Quadratic effect was found to üMI, NDFI, TCHüI, and NFCI, while for MM1 and CPI were observed decreasing linear effect. There is no inf1uence of cactus levei on MEl and EEI (2.7±0.3 Mcal e 25.4±4.9 g, respectively). Water intake from diet increased with spineless cactus inc1usion, been observed inverse behaviour for water drinking. Total water intake was not intluenced by inclusion of spineless cactus (4.8±0.7 L), as DM and üM aparent digestibilities. It was observed linear effect for CP aparent digestibility, while NDF aparent digestibility had quadratic effect, with minimum value of 19.1 % at the levei of 27.5% of cactus. Feed conversion was improved with the inclusion of cactus, decreasing DMI in 12.8 g/kg of ADG to each unit of increasing in spineless cactus leveI. There was quadratic effect for both, crude protein and metabolizable energy feed convertion, as well as ADG, whose maximum value was 0.26 kg at the levei of 35.0% of cactus in the diet. The inclusion of spineless cactus increased the crude margin and the cost per kg of carcass was lower for the levei of 67.9%. The cactus levei of 35.0% in the diet resulted in higher growth rate, however, from the point of economic view, the inclusion of 67.9% promoted the best income, with profitability of 69.0%. The results indicate that the use of spineless cactus (Opuntia ficus-indica Mill), at the studied levels, in oldman saltbush (Atriplex nummularia L.) hay-based total mixed diets presents as a viable alternative for lambs production in fedlot. / Objetivou-se, com este trabalho, avaliar o desempenho, consumo de nutrientes, digestibilidade e rentabilidade de cordeiros Santa Inês alimentados com níveis crescentes de palma forrageira (Opuntia ficus-indica MiII). Quaren,ta cordeiros não castrados, com peso corporal inicial de 19,46±2,35 kg e quatro meses de idade, foram distribuídos em um delineamento inteiramente casualizado, com quatro dietas e 10 repetições. Os níveis de palma influenciaram o CMS (kg, %PC e PCO,75), sendo observado comportamento quadrático com valores máximos de 1,29 kg, 4,84%PC e 109,75 g/PCO,75, respectivamente, para o nível de 28,8; 21,4 e 23,6% de palma na dieta. Os CMO, CFDN, CCHOT e CCNF sofreram efeito quadrático, enquanto para os CMM e CPB foi observado efeito linear decrescente. Os CEM e CEE não foram influenciados pelo nível de palma, com média de 2,7±0,3 Mcal e 25,4±4,9 g, respectivamente, O consumo de água proveniente da dieta aumentou linearmente com a inclusão de palma, sendo observado comportamento inverso para o de água de bebida. O consumo total de água não foi influenciado pelo nível de palma (4,8±0,7 L), assim como as digestibilidades aparentes da MS e MO. Para a digestibilidade aparente da PB, foi observado efeito linear decrescente, enquanto a digestibilidade aparente da FDN sofreu efeito quadrático com valor mínimo de 19,1% no nível de inclusão de 27,5% de palma. A CA foi incrementada com a inclusão de palma, sofrendo redução no CMS de 12,8 g/kg de GPD para cada aumento de 1 % no nível de palma da dieta. Observou-se efeito quadrático para as conversões alimentares da PB e EM, assim como para o GPD, cujo valor máximo foi de 0,26 kg para o nível de 35,0% de palma. A inclusão de palma incrementou a margem bruta, e o custo por kg de carcaça foi menor para o nível de 67,9%. O nível de 35,0% de palma na dieta resultou em maior taxa de crescimento; todavia, do ponto de vista econômico, a inclusão de 67,9% promoveu melhor retorno financeiro, com rentabilidade de 69,0%. Os resultados indicam que a utilização de palma forrageira (Opuntia jícus-indica Mill) nos níveis estudados, em dietas completas à base de feno de erva-sal (Atriplex nummularia L.), apresenta-se como alternativa viável para a produção de cordeiros em confinamento.
60

Obsah vybraných fenolických látek v některých zástupcích rodů Chenopodium L. a Atriplex L. / The content of selected phenolic compounds in representatives of Chenopodium L and Atriplex L genera.

DĚKANOVÁ, Zdeňka January 2010 (has links)
The thesis deals with measuring the content of chosen phenolic substances in some specimen of the genera Chenopodium L. and Atriplex L. Two independent analytical methods were used to determine the content of phenolic substances, namely the Micellar Electrokinetic Capillary Chromatography (MECC) method and the High - Performance Liquid Chromatography (HPLC) method. Two cultured species of the genera Spinacia and Atriplex, three freely growing specimen of the genus Chenopodium and three freely growing species of the genus Atriplex were analysed. The analysis concerned the leaves and the inflorescence of these species.The total content of quercetin and rutin was determined by the MECC method. The highest total content of quercetin was found in the leaves of the Garden Orache (4240 mg/kg of dry matter), the lowest total content of quercetin was found in the inflorescence of the Atriplex prostrata DC. (19.6 mg/kg of dry matter). Rutin was only found in four samples, the rest of the samples contained rutin in quantities below the limit of quantification. The highest content of rutin was found in the leaves of the Lamb´s Quarters (868 mg/kg of dry matter).

Page generated in 0.0737 seconds