• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 10
  • 1
  • 1
  • Tagged with
  • 12
  • 10
  • 7
  • 7
  • 6
  • 5
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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.
11

MICRORGANISMOS SIMBIONTES, MATÉRIA ORGÂNICA E ADUBAÇÃO NITROGENADA NO DESENVOLVIMENTO E NUTRIÇÃO DO MIRTILEIRO CV. CLIMAX EM AMBIENTE PROTEGIDO

Santana, Kamila 24 June 2016 (has links)
Made available in DSpace on 2017-07-25T19:31:00Z (GMT). No. of bitstreams: 1 Kamila Santana.pdf: 1363071 bytes, checksum: 4f5da813f22ced41d3b26851a927779f (MD5) Previous issue date: 2016-06-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The blueberry is an agricultural crops recently introduced in Brazil and lots of researches are turning to develop and adapt it to the country. Due to its low amount of root hair, it forms associations with microorganisms to expand its zone of nutrient uptake, being the nitrogen the most required element. At this work it was observed the interaction of this cultivation with the inoculum Azospirilum brasilense and Trichodema asperellum into different substrates or doses of nitrogen fertilization. The experiment was performed with cv. Climax and the plants conditioned in pots in greenhouse, under trial design of randomized blocks, factorial 3x3. The considered factors were inoculation (A. brasilense, T. asperellum or without inoculation) and formulation of the substrates (5; 20 e 35% of organic matter – hardened cattle manure) or, at the second experiment, inoculation (A. brasilense, T. asperellum or without inoculation) and doses of nitrogen (0, 10 and 15 g f N plant-1 – provided as urea). The larger quantity of organic matter provided the highest averages relating to physiological (transpiration, water use efficiency and carboxylation efficiency) and growth variables (foliar limb area, total foliar area and rate of relative growth), although, for some of them, it has not differed from plants grown with 20% of organic matter. With 30% of O.M., the inoculation with T. asperellum showed superior averages in CO2 assimilation (A), carboxylation efficiency (A/Ci) and rate of relative growth (RRG). The nitrogen doses positively affected A/Ci, clorophyll amounts, foliar area (limb and total) and foliar nitrogen concentration, although it not differing between 10 or 15g of N plant-1. For the accumulation of the nutrients Ca, Mg, S, Fe and Zn, the nitrogen fertilization did not represent higher foliar levels, even though this might be related to a dilution effect. / O mirtileiro é uma cultura recentemente introduzida no Brasil, sendo que várias pesquisas tem-se voltado para seu melhor desenvolvimento e adaptação no país. Por possuir poucos pelos radiculares, forma associações com microrganismos afim de aumentar sua zona de absorção de nutrientes, sendo o nitrogênio o elemento absorvido em maior quantidade. Neste trabalho, observou-se a interação dessa cultura com os inóculos Azospirillum brasilense e Trichoderma asperellum em diferentes substratos ou doses de adubação nitrogenada. O experimento foi realizado com a cv. Clímax e as plantas acondicionadas em vasos, em casa de vegetação, sob delineamento experimental de blocos casualizados em esquema fatorial 3x3. Os fatores analisados foram inoculação (A. brasilense, T. asperellum ou sem inoculação) e formulação dos substratos (5; 20 e 35% de matéria orgânica – esterco bovino curtido) ou, no segundo experimento, inoculação (A. brasilense, T. asperellum ou sem inoculação) e doses de nitrogênio (0, 10 e 15 g de N planta-1 – fornecido como ureia). A maior proporção de matéria orgânica propiciou as maiores médias em relação a variáveis fisiológicas (transpiração, eficiência no uso da água e eficiência de carboxilação) e de crescimento (área de limbo foliar, área foliar total e taxa de crescimento relativo), embora, para outras, não tenha diferido das plantas cultivadas com 20% de matéria orgânica. Com 35% de M.O., a inoculação com T. asperellum apresentou médias superiores em assimilação de CO2 (A), eficiência de carboxilação (A/Ci) e taxa de crescimento relativo (TCR). As doses de nitrogênio influenciaram positivamente A/Ci, teores de clorofila, área foliar (de limbo e total) e concentração foliar de nitrogênio, embora não diferindo entre 10 ou 15g de N planta-1. Para o acúmulo dos nutrientes Ca, Mg, S, Fe e Zn, a adubação nitrogenada não representou maiores teores foliares, embora isto possa estar relacionado a um efeito de diluição.
12

Habitat relationships of seven breeding bird species in the Leon River Watershed investigated at local scales

Juarez Berrios, Edwin Alfredo 17 February 2005 (has links)
Over the past 100–150 years Texas rangelands have dramatically changed from native open savannahs to dense woodlands. On the Edwards plateau, a major management concern is the increasing encroachment of Ashe juniper (Juniperus ashei). Preceding an anticipated brush management program, I investigated the presence, co-occurrence, and habitat relationships of 7 breeding bird species in the Leon River Watershed in central Texas, USA: black-capped vireo (Vireo atricapillus), golden-cheeked warbler (Dendroica chrysoparia), northern bobwhite (Colinus virginianus), white-eyed vireo (Vireo griseus), Bell’s vireo (Vireo bellii), painted bunting (Passerina ciris), and brown-headed cowbird (Molothrus ater). Vegetation characteristics were compared between sites occupied by each species and unoccupied sites using univariate analysis. Models for predicting species site occupancy were developed (using logistic regression) based on habitat characteristics correlated with the presence of each species. Two species of special concern, the endangered black-capped vireo and golden-cheeked warbler occupied 5.6% of sites and 13.8% of sites respectively, while the brood parasite brown-headed cowbird was the most widespread, occupying 86.8% of sites. Species co-occurrence patterns revealed significant associations between the golden-cheeked warbler and each of 5 other species. For most species, variables included in habitat models could be explained by knowledge of species known habitat associations. For example, the black-capped vireo was positively associated with increasing low-growing (<1.5 m) hardwood cover and with Low Stony Hill ecological sites. The golden-cheeked warbler was positively associated with increasing density of larger juniper trees, increasing variability in vertical vegetation structure, and decreasing midstory canopy of deciduous nonoaks (e.g., cedar elm [Ulmus crasifolia]). It also preferred Low Stony Hill and Steep Adobe ecological sites. Site occupancy seemed to be driven by variables that describe overall vegetation structure. In particular, cover of low-growing non-juniper vegetation and juniper tree density appeared to be important in determining site occupancy for several species. Although the models constructed were not very robust, resource managers can still benefit from such models because they provide a preliminary examination of important controlling variables. Managing rangelands to maintain or restore a mosaic of juniper patches and open shrublands are likely to help meet the habitat requirements of these bird communities.

Page generated in 0.0349 seconds