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  • 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.
31

Experimental Assessment of Butomus Umbellatus L. Growth and Expansion Using a Mesocosm Approach

Carter, Christian 15 August 2014 (has links)
Over the last century, flowering rush (Butomus umbellatus L.: Butomaceae) has escaped its native Eurasian range and has become a problematic species in North America. As an aquatic invasive species, flowering rush has degraded native wetlands and has interfered with human water usage. Although experimental work has been done regarding the reproductive biology of the species, few empirical studies regarding the ecology of the species have been conducted. The research reported here demonstrates that flowering rush is capable of aggressive clonal growth and propagation, and can perform well along a depth gradient from zero to 132cm. Proper management and control of invasive species relies on sound ecological knowledge of the target species, and this work aims to help gather that information.
32

Dune to shore: The relationship between vegetative dune systems and shoreline stability in barrier islands

Hogue, Walter Hastings 08 August 2023 (has links) (PDF)
Dauphin, Petit Bois, and Horn Island form the Alabama gulf-barrier chain directly south of Mobile Bay. Many studies have targeted local climate stressors and the flux of longshore currents as factors for erosional and accretional changes on these islands, but little attention is paid to the degradation of their vegetative dune-systems as a contributor to their shoreline morphology (Hanley et al., 2014; Smith, 2018; Byrnes, 2010). This study fills this literary gap, utilizing GIS raster classification and Digital Shoreline Analysis System to measure vegetative health and shoreline change on these islands and verify a relationship between these two factors. The distribution of vegetation on the Barrier Islands has been shown to mitigate shoreline changes, particularly ocean-side erosion. This thesis has significance in that it geo-statistically verified the importance of natural infrastructure, vegetative dune systems, in shoreline stability using GIS.
33

An Introduction to Local Multipoint Distribution Services with an Investigation of the Effects of Vegetation on the Radio Channel

Manning, Edward Patrick 28 January 1999 (has links)
This thesis takes the reader through an overview of issues pertinent to Local Multi-point Distribution Services (LMDS). The reader will first learn what LMDS is and then review the system architectures that are made available for LMDS technologies. After summarizing the basics of LMDS, we will compare it with some competing technologies. The reader will then be guided through the aspects of millimeter (mm) wave radio link design. This should be a good lead into the experiment section, since it is suspected that the reader would want to be aware of what design techniques are involved in mm-wave radio link design and what issues may pose potential problems and how they may be mitigated. Of the potential problems posed in the mm-wave radio link design section, one will be further investigated experimentally. This is the investigation of the effect of vegetation on the magnitude, phase and error vector magnitude (EVM) performance of an LMDS channel. The motivation for this experiment came from the review earlier work, which showed an unexpected relationship between carrier to noise ratio (C/N) and bit error rate BER. / Master of Science
34

fMRI for severely brain injured patients : a media analysis

Samuel, Gabrielle January 2014 (has links)
This thesis is set in the context of social science’s interest in the generation of expectations, the news media, and neurotechnologies. It is a qualitative case study that examines the nature and impact of news media reporting of some pioneering research, which used functional magnetic resonance imaging in an attempt to diagnose and communicate with severely brain-injured individuals. Previous news media studies exploring neurotechnologies have been quantitative, or have tended to focus on how or why the news media represents neurotechnologies and/or the impact of the reporting, but rarely all three together. My thesis looks at all three aspects of the news media reporting of my case study. I draw on three sets of empirical data. First, those related to the production of the media - the press releases which reported the research; ten semi-structured interviews with science press officers; and the relevant expert comments posted on the Science Media Centre’s website. Second, 51 newspaper articles reporting the research. Third, five semi-structured interviews with relatives of severely brain-injured patients. I show that the mood of excitement and ‘breakthrough’ present in the press release reporting of this research was closely echoed in the news coverage. This excitement influenced the views and beliefs of only some of the relatives I interviewed. I then examine the nature of hype and by drawing on Haraway’s concept of ‘situated knowledges’ (1988) I argue that individuals view hype differently depending on their profession, industry and/or socio-cultural background. Finally, I show how whilst both the news media and the scholarly literature portrayed this research as ethically contentious, the issues most prominently discussed by scholars and/or journalists do not necessarily equate with relatives’ concerns. My findings aim to contribute to the sociology of expectations, media theory, the sociology of bioethics and the public understanding of science.
35

Ecology, Distribution, Toxigenicity and Diversity of Aflatoxin-Producing Fungal Communities in Maize Fields of Mexico and Interactions of these Fungi with Native Maize Landraces

Ortega-Beltran, Alejandro January 2012 (has links)
Aflatoxins are carcinogenic mycotoxins most frequently associated with the filamentous fungus, Aspergillus flavus. These potent toxins pose serious health threats and their concentrations in foods are widely regulated. Maize, a critical staple of billions, is frequently contaminated with aflatoxins. Development of commercial maize hybrids with superior resistance to aflatoxin contamination has been sought for over 30 years without success. Analyses of native maize land races (MLRs) from Mexico revealed several accessions with significant resistance to both aflatoxin contamination and fungal reproduction. Physical barriers are important components of MLRs resistance. Traditional use of MLRs may reduce human exposure to aflatoxins. MLRs may contribute resistant genes of significant value in breeding for aflatoxin resistance. In Mexico, maize is produced from<10 to over 2,000 masl. Elevation had only minor influence on community compositions of aflatoxin-producing fungi associated with maize over three years in Sonora, Mexico. Most variation in community structure occurred between years. Dominant vegetative compatibility groups (VCGs) differed among years but were detected in similar frequencies across four agroecological zones. Multiple locations and multiple years must be sampled to obtain realistic assessments of the most successful VCGs. Elevated frequencies of VCG YV150 throughout Sonora during 2006 led to investigate genetic diversity within this VCG using microsatellite loci. The 2006 increases were attributed to rapid increase of a single clone. Examination of YV150 isolates collected over 20 years in the US and Mexico revealed several haplotypes and two genetically distinct populations, which were composed of isolates containing only a population specific mating-type idiomorph. Microsatellite loci in each population were in gametic equilibrium. Gene flow between isolates with different idiomorphs was not detected. VCG YV36, to which the biocontrol agent AF36 belongs, was found to be endemic to Mexico. Microsatellite loci revealed diversity within YV36 from Mexico, but all isolates harbored the single nucleotide polymorphism in the aflatoxin polyketide synthase gene, pksA, that confers atoxigenicity to AF36. Three YV36 isolates also had deletions in pksA suggesting continued degradation. Presence of endemic YV36 isolates in Mexico may facilitate rapid regulatory approval of AF36 for use in prevention of aflatoxin contamination of maize in Mexico.
36

Functional connectivity in disorders of consciousness

Merz, Susanne January 2013 (has links)
Disorders of consciousness (DoC) are a group of disorders that can occur after severe brain injury. DOC have been subdivided based on behavioural observations into: Coma, lacking any signs of wakefulness or awareness; the vegetative state, showing signs of wakefulness but lacking any signs of awareness; and the minimally conscious state, showing signs of wakefulness and infrequent and irregular signs of awareness. The so-called locked-in syndrome, a state where both wakefulness and awareness are intact, but no communication is possible due to a lack of muscle function, does not belong to the disorders of consciousness. However, it is difficult to distinguish the locked-in syndrome from DoC diagnostically, because consciousness can only be shown through consistent responses to a command and current methods for assessing consciousness rely on behavioural responses. Patients with locked-in syndrome might not be able to move voluntarily at all in the most severe cases. Behavioural assessment would then classify them as unaware. While this is an extreme and rare case, it illustrates the problem behavioural assessment poses. Such assessments are unable to distinguish the effects of impaired muscular control from impaired awareness, when either has reached an extreme level of severity. Brain damage that does not affect consciousness itself can nevertheless affect the results of the behavioural assessment of consciousness. It is then hardly surprising that the diagnosis of DoC is associated with a high level of uncertainty. The advantage of brain imaging methods is that they do not rely on the patients ability to produce a consistent behavioural response. There have therefore been efforts to use the brain imaging methods electroencephalography, positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) to aid diagnosis of disorder of consciousness. PET and fMRI have successfully been used to identify regions of difference in some patients in a DoC. Task-based fMRI has been used to identify intact consciousness, using tasks that require explicit understanding of instructions and wilful modulation of brain activity, but no motor control. One of these tasks consists of periods where the participant imagines playing tennis alternated with periods of rest. The ability to follow this paradigm is evidence of consciousness, and a few patients with a diagnosis of DoC have been shown to be able to do this task. However, the tennis task requires high order processing of the tasks requirements and the majority of patients does not respond to this task. fMRI tasks that test sensory modalities instead of consciousness have been used to show retained brain function even in DoC patients that do not respond to the tennis task. In this work the tennis task and a battery of other tasks including tactile, visual and auditory stimulation, were studied on a group of DoC patients. It was found that none of the patients responded to the task of imagining playing tennis, but retained sensory function could be identified in three out of seven patients. This highlights a strength of fMRI, namely that it can identify retained brain function below the level that is necessary for consciousness. However, the results also show that more than half of the patients studied here, did not show retained brain activation during the fMRI scan. For any of the patients that did not show a response, this can be due to an actual lack of retained brain function, but it can also be due to limitations of the task-based fMRI analysis. The fMRI tasks only test one sensory function at a time, for a short time. Thus a visual fMRI task for example, can only provide information about areas of the brain, that are involved in visual processing. And when vigilance is fluctuating, retained brain function can remain undetected, if vigilance is low during the scan. Functional connectivity analysis is a method to study internal connections between brain areas that is not dependent on an external task. It models the brain as a network of interconnected regions and studies the characteristics of this network. Graph theory is a mathematical field that has found application on many other fields using network analysis, like social sciences, metabolic network modelling or gene network modelling. In fMRI analysis, graph theory has been used to study different phenomena and pathologies and global network properties have been shown reproducibly. The work presented here aims to develop new methods based in graph theory aiding the identification of residual brain integrity. To allow an assessment of the brain network topology and its use in the assessment of residual brain integrity, a novel method was designed based on a graph theoretical measure. The method, termed Cortical Hubs And Related network Topology (CHART) is a two stage procedure. The rst stage identifies statistically significant differences in functional connectivity between two groups, using a measure of the average connectivity of each voxel, the weighted global connectivity. The second stage highlights the topology of the networks associated with those differences. Two fMRI datasets, with different underlying tasks and pathologies were used to test the CHART method. The first dataset was acquired from a group of patients with severe depression. It contrasted the state of the brain before and after successful treatment with electroconvulsive therapy. In this patient group the CHART method was able to identify an area of hyperconnectivity in the depressed state, compared to the treated state. This area of hyperconnectivity was connected to areas that had priorly been shown to be overly connected in the depressed state. The second dataset consisted of DoC patients, that had been extensively assessed behaviourally. Half of the patients were diagnosed to be in a vegetative state, the other half was diagnosed to be in a minimally conscious state. The first stage of CHART identified several areas of difference based on the weighted global connectivity. The second stage highlighted that the observed global differences were due to an overall lack of extended functional connectivity in the vegetative state patients. The addition of a healthy control group in stage two allowed comparison not only between the two DoC groups, but also with the healthy group. In summary it was observed that the spatial extent of the connectivity seen in the minimally conscious group resembles the spatial extent of the connectivity seen in the healthy control group, while the spatial extent of connectivity observed in the vegetative state group was minimal, compared to both healthy and minimally conscious group. Thus the spatial extent of connectivity is a distinguishing property for the vegetative state group studied here. However the first stage of the CHART method is a group based method. In disorders of consciousness, where the underlying pathology is different from case to case, this concept is problematic. Finding a meaningful group of interest is difficult or impossible, because lesions differ in location and extent. Individual differences in connectivity can be expected to be large, and a generalisation of the CHART result might not lead to improved diagnosis for every patient. For diagnosis, the patients individual characteristics must be taken into account. An additional objective of this work was therefore to develop a method to compare a single patient to a group of controls. An approach based on regression modelling was tested but failed to provide the necessary statistical sensitivity to detect impaired connectivity. In conclusion the CHART method developed in this work provides insights into the functional connectivity of a group of DoC patients. To assist diagnosis, further development of a method to compare a single subject to a group of controls will be important.
37

Rooting stem cuttings of shantung maple (Acer truncatum), mound layering shantung and caddo sugar maples (Acer saccharum), and using Eastern redcedar (Juniperus virginiana) as a substrate component in stem cutting propagation

Brock, Justin Alan January 1900 (has links)
Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Jason J. Griffin / Heat and drought tolerance make shantung maple (Acer truncatum) and caddo sugar maple (A. saccharum) good candidates for midwestern landscapes. Improving cutting propagation or mound layering techniques could increase the availability of these species. The influence of time of year, cutting position, and auxin concentration, formulation, and solvent on rooting of stem cuttings of shantung maple was investigated. Semi-hardwood cuttings rooted best (55%). Generally, rooting percentage decreased as indole-3-butyric acid (IBA) concentration increased. Cutting position, auxin formulation, and solvent did not affect rooting. Mean root number and mean root length were unaffected by treatments. Results suggest semi-hardwood cuttings and low IBA concentrations [< 2500 ppm (0.25%)] promote rooting. Auxin concentration influenced rooting of caddo and shantung maple mound layered shoots. Rooting peaked at 15,000 ppm (1.5%) IBA for both caddo (71%) and shantung maples (34%). Mean root number for caddo, but not shantung, increased as IBA concentration increased. Differences in mean root length were not significant. Growers may now propagate caddo maple by mound layering. For shantung maple propagation, stem cuttings are recommended. Propagation substrates can strongly influence rooting success of stem cuttings. Eastern redcedar (Juniperus virginiana) chips (ERC) have been suggested as a propagation substrate component. This report investigated ERC as a perlite substitute in a 3 perlite: 1 sphagnum peat moss (v/v) rooting substrate. Stem cuttings of spreading euonymus (Euonymus kiautschovicus), forsythia (Forsythia x intermedia), English ivy (Hedera helix), lantana (Lantana camara), and coleus (Solenostemon scutellarioides) were rooted in substrates containing increasing concentrations of ERC hammer milled to pass a 4.8 mm (0.19 in) screen. All species rooted well (≥95%) in all substrates except forsythia which rooted poorly in all substrates (8% to 36%). ERC did not affect mean root number or mean root length in any species except spreading euonymus where mean root number peaked at 0% and 100% ERC content and mean root length decreased with increasing ERC content. Bulk density, container capacity, and total porosity increased as ERC replaced perlite. Physical properties of all substrates were suitable for cutting propagation. ERC can effectively replace perlite in rooting substrates for many ornamental species.
38

Estudo da periodicidade do crescimento, fenologia e relação com a atividade cambial de espécies arbóreas tropicais de florestas estacionais semideciduais. / Study on the periodicity of growth, phenology and the relation with the changing activity of tropical arboreal species in semidecidual stately forests.

Maria, Vivian Ribeiro Baptista 08 April 2002 (has links)
O presente trabalho foi desenvolvido em áreas florestais naturais e implantadas de Florestas Estacionais Semideciduais remanescentes do planalto paulista com o objetivo de estudar a periodic idade de crescimento, fenologia e atividade cambial. A pesquisa visa determinar a idade e o crescimento de 23 espécies arbóreas tropicais e subtropicais, contribuindo, desta forma, com a aquisição de conhecimentos científicos básicos sobre a biologia e a ecologia do crescimento das mesmas. A compreensão da dinâmica das populações florestais e o comportamento de crescimento das suas espécies foram obtidos a partir do acompanhamento mensal da periodicidade de crescimento através da implantação de faixas dendrométricas permanentes nos troncos das árvores e observações dos estágios fenológicos (folhas, brotamento, floração e frutificação), avaliados mensalmente durante o período de janeiro de 2000 a outubro de 2001 em relação às variações climáticas. A determinação da idade e taxa de crescimento das árvores foram obtidas através da contagem e mensuração da largura dos anéis de crescimento a partir de "baguetas" coletadas com auxílio da sonda de Pressler, na altura do DAP. Os resultados deste trabalho permitiram concluir que as variações das taxas de crescimento em circunferência do tronco das árvores estão estreitamente relacionadas à precipitação e a disponibilidade de água no solo na estação chuvosa e a ocorrência de um período de seca com redução e/ou cessação da atividade cambial. Da mesma forma, os estágios fenológicos estão relacionados com fatores abióticos como o clima e, em especial, às variações de precipitação entre as estações seca e úmida. As informações sobre a influência de fatores ambientais na taxa de crescimento das espécies arbóreas permitirão a adoção de medidas científicas que visem a preservação da biodiversidade desses ecossistemas frágeis e constantemente ameaçados. / This paper was developed in natural and implanted forest areas of remaining Semidecidual Stately Forests in Sao Paulo plains, with the aim of stud ying the periodicity of growth, the phenology and its changing activity. The research seeks determining the age and growth of 23 tropical and semitropical arboreal species, thus contributing with the gathering of basic scientific knowledge on the biology and the ecology of their growth. The understanding on the forests’ populations’ dynamics and the behavior of their growth were obtained with a monthly observation through the inserting of permanent dendometric strips into the trees trunks and through the phonological stages analysis (leaves, sprouting, blooming and fruiting), evaluated from January 2000 to October 2001 because of the weather variations. The age and growth rate determination was obtained counting and measuring the growth rings starting with wood samples collected with the help of a Pressler probe, at the DAP height. The results of this paper led to the conclusion that the variations on the perimeter of the trunk growth rate are closely related to the rainfall and water availability in the soil under the rainy season and the occurrence of a drought period with reduction and/or changing activity cessation. Likewise, the phenological stages are related to abiotic factors like weather and, especially, to rainfall variations between the dry and humid seasons. The information on the influence of environmental factors on the growth rate of arboreal species will facilitate the adoption of scientific measures seeking the preservation of the biodiversity of these ecosystems so fragile and constantly under threat
39

Produção de mudas de seringueira em viveiro suspenso / Production of rubber tree seedlings in suspended nursery

Borelli, Karla 22 January 2016 (has links)
Dentre os métodos utilizados na propagação vegetativa de espécies florestais, a enxertia por borbulhia é a mais empregada para a seringueira (Hevea brasiliensis). Nesse sistema de produção de mudas, os porta-enxertos são formados diretamente no solo ou em sacos de polietileno preenchidos com solo. Embora essa seja uma prática comum nos viveiros, mudanças nos parâmetros legais foram propostas a fim de alterar o sistema de produção de mudas, principalmente no que diz respeito ao cultivo dos porta-enxertos. Para atender essas alterações, objetivou-se desenvolver um protocolo de produção de mudas de seringueira em bancadas suspensas. Para isso, foram conduzidos dois experimentos (descritos no cap. II e III) em Piracicaba - SP. No capítulo II, propõe-se a produção de hastes verdes em minijardim clonal hidropônico com leito de areia. Doses crescentes de nutrientes via fertirrigação foram testadas. Avaliou-se a produtividade do minijardim em função da fertirrigação e o aproveitamento das hastes verdes para a enxertia. Os resultados obtidos, mostraram que a fertirrigação afetou a produção de hastes verdes de seringueira em condições de minijardim clonal, sendo 1,5 mS cm-1 a condutividade elétrica ideal da solução nutritiva para produção de hastes verdes nesse sistema. Mesmo sob sistema hidropônico em casa de vegetação, forte sazonalidade da produção foi observada. As melhores estações do ano para coletar hastes verdes aptas às enxertias por borbulhia e garfagem foram à primavera e o verão. Nesse período recomenda-se elevar a condutividade elétrica da solução para 2,0 mS cm-1. Para o experimento descrito no capítulo III, porta-enxertos foram produzidos em viveiro suspenso, utilizando substrato comercial. Diferentes métodos de enxertia foram testados (borbulhia, garfagem em fenda cheia e fenda lateral) em porta-enxerto com diferentes diâmetros. Os enxertos utilizados foram obtidos no experimento do cap. II. Obteve-se sucesso com a enxertia por borbulhia e a enxertia por garfagem em fenda cheia, sendo possível verificar redução no tempo de produção de mudas de seringueira em condições de viveiro suspenso. No entanto, é necessário ajustes para obter maior sobrevivência das enxertias sob essas condições. / Among methods used for the vegetative propagation of forest species, budding is the most used for rubber tree (Hevea brasiliensis). In this system the rootstocks are produced directly on the soil or in polyethylene bags using soil as substrate. Although this is a common practice in the commercial nurseries, changes in the law were proposed for the planting material production system, particularly in the production of rootstocks. To meet these changes, this work aimed to develop a protocol for the production of rubber tree in suspended benches. There conducted two trials (chapter II and chapter III) in suspended bed in Piracicaba - SP. In chapter II was proposed the production of green scions in hydroponic clonal mini garden in function of fertigation. The mini garden yield was accessed by green scions productions and fertigation. It was found that the fertigation affected the production of green scion of rubber tree under clonal mini garden conditions. The electric conductivity of 1.5 mS cm-1 was the best solution for this system. Even in the hydroponic clonal mini garden in a greenhouse, a strong seasonality of growth was found. The best season to produce green scions in this system was summer and spring. In these seasons it is recommend using the EC of solution of 2.0 mS cm-1. In the experiment described in the chapter III, the rootstocks were produced in suspended benches, using a commercial substrate. Different methods of grafting were tested (budding, grafting in full and lateral cleft) in rootstocks of different diameters. The scions used were obtained in the experiment of chapter II. Success was obtained with the budding and grafting in full cleft, being possible to reduce the period for rubber tree production under suspended benches conditions. Adjustments are needed to get increased grafting survival under these conditions.
40

Análise de imagens no desenvolvimento e status de fósforo do minitomateiro grape cultivado em sistema semi-hidropônico / Image analysis of the development and phosphorus status of the mini tomato grown in a semi-hydroponic system

Magalhães, Leonardo Pinto de 29 October 2018 (has links)
A análise de imagens é uma das formas de avaliar o desenvolvimento das plantas, tanto para correlacionar aspectos biofísicos dos mesmos, como para a detecção de doenças. Através das imagens podem ser calculados índices vegetativos que se correlacionem com os teores de nutrientes nas folhas. Com essa perspectiva, o presente trabalho objetivou avaliar quais indices vegetativos melhor se correlacionariam com a taxa de fósforo nas folhas de tomateiros. Foi realizado o cultivo de uma cultivar de minitomate, com cinco doses de fósforo (0, 25, 50, 75 e 100%) do P recomendado (na formulação da solução nutritiva). Em diferentes etapas do desenvolvimento da planta foram coletadas amostras das folhas para obtenção das imagens, através de escâner e máquina fotográfica, e diagnose foliar. Foram determinadas as biorrespostas das plantas ao longo do tempo. Uma rede neural artificial foi desenvolvida para estimar os teores de fósforo foliares no minitomate grape. A análise do desenvolvimento da planta permitiu concluir que a dose 100% de P2O5 utilizada no experimento foi suficiente para suprir a demanda nutricional do minitomateiro. Aos 64 dias após o transplantio (DAT) foi observada a maior queda nos teores de fósforo nas folhas, coincidindo com o amadurecimento dos frutos. Propõe-se, para a cultivar estudada, que a dignose foliar seja feita aos 50 DAT. Os índices vegetativos obtidos pela análise de imagem e selecionados pela análise de componentes principais (ICVE e Bn, tanto da parte abaxial quanto adaxial) podem ser utilizados para estimar a diagnose foliar de P na cultivar de minitomate grape. A avaliação dos índices vegetativos indicou que a obtenção de imagens com o escâner é mais adequado do que com a câmera fotográfica. Para a cultivar estudada, verificou-se que na dosagem de 100% de P2O5 teor de P nas folhas fica abaixo de 4,0 g kg-1. Em relação à rede neural desenvolvida, ao categorizar os valores de P de acordo com a literatura, a mesma obteve uma taxa de acerto de 90%. / The analysis of images is one of the ways to evaluate the development of plants, both to correlate biophysical aspects of the same, as for the detection of diseases. Through the images can be calculated vegetative indexes that correlate with the contents of nutrients in the leaves. With this perspective, the present studied aimed to evaluate which vegetative indexes would best correlate with the phosphorus rate in tomato leaves. A minitomato grape cultivar with five phosphorus doses (0, 25, 50, 75 and 100%) of the recommended P (in the formulation of the nutrient solution) was carried out. At different stages of plant development, leaf samples were collected to obtain the images, with scanner and camera, and foliar diagnosis. The bio-responses of plants were determined over time. An artificial neural network was developed to estimate leaf phosphorus levels in the grape minitomate. The analysis of the development of the plant allowed to conclude that the dose 100% of P2O5 used in the experiment was enough to supply the nutritional demand of the minitomateiro. At 64 days after transplanting (DAT), the highest drop in phosphorus content in the leaves was observed, coinciding with the ripening of the fruits. It is proposed, for the studied cultivar, that the leaf dignity should be made at 50 DAT. The vegetative indexes obtained by the image analysis and selected by the principal components analysis (ICVE and Bn, both abaxial and adaxial) can be used to estimate the leaf diagnosis of P in the minitomate grape cultivar. The evaluation of vegetative indexes indicated that obtaining images with the scanner is more appropriate than with the photographic camera. For the cultivar studied, it was verified that in the dosage of 100% of P2O5 content of P in the leaves is below 4.0 g kg-1. In relation to the developed neural network, when categorizing the P values according to the literature, it obtained a 90% correctness rate.

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