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RICCI, SARA. "Study of biotic and abiotic stresses in Solanaceae by metabolic and proteomic approaches". Doctoral thesis, Università di Foggia, 2017. http://hdl.handle.net/11369/363315.
Pełny tekst źródłaEscalante, Pérez María. "Poplar responses to biotic and abiotic stress". kostenfrei, 2009. http://nbn-resolving.de/urn/resolver.pl?urn=nbn:de:bvb:20-opus-46893.
Pełny tekst źródłaKarim, Sazzad. "Exploring plant tolerance to biotic and abiotic stresses /". Uppsala : Dept. of Plant Biology and Forest Genetics, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200758.pdf.
Pełny tekst źródłaMatheson, Leah J. "Abiotic and biotic reductive dehalogenation of halogenated methanes /". Full text open access at:, 1994. http://content.ohsu.edu/u?/etd,241.
Pełny tekst źródłaJain, Ritu Shree. "Rice response to simultaneous biotic and abiotic stresses". Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/6415/.
Pełny tekst źródłaVENULEO, MARIANNA. "Algal responses to abiotic and biotic environmental changes". Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245503.
Pełny tekst źródłaAlgae exhibit a large variety of physiological responses to the environmental changes. Such heterogeneity of responses, which is a major determinant of species interaction in natural algal assemblages, was the target of my research. My results show that different species are differently prone to change their cell composition in response to environmental changes, depending on the type and duration of the perturbation. When algae are exposed to changes in the N source and in the CO2 availability, for instance, homeostasis appears as a much more common strategy than usually believed. No link between the response modes and the taxonomy of the examined species was found. I paid special attention to Chromera velia, a photosynthetic relative of apicomplexan parasites that is likely involved in symbiotic associations with scleractinian corals. This alga seems perfectly capable of copying with very high CO2. Life at high CO2 stimulates the overall organic C production of C. velia, increases its nutrient use efficiency and changes the stoichiometric relationships among elements within the cell. The high CO2 concentrations that has been reported in the animal tissue surrounding the photosynthetic cells may therefore facilitate C. velia life in symbiosis. Finally, I have demonstrated that the interactions between algae and environment can affect the relationships between algae and their grazers. My experiments show that the copepods are able to discriminate among algae identical in all aspects but in cell composition, while the rotifers are not. Therefore, the nutritional history of algae, which has the potential to affect algal cell composition, appears as a major determinant of the relationships between algae and grazers.
Madeo, M. "MEDICINAL PLANT RESPONSE TO ABIOTIC AND BIOTIC STRESS". Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150114.
Pełny tekst źródłaMacDonald, Arthur Andrew Meahan. "Abiotic and biotic factors creating variation among bromeliad communities". Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58954.
Pełny tekst źródłaScience, Faculty of
Graduate
Black, Kyrsten E. "Root longevity as affected by biotic and abiotic factors". Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361797.
Pełny tekst źródłaGerald, Gary Wayne II. "Consequences of abiotic and biotic factors on limbless locomotion". Miami University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=miami1218208497.
Pełny tekst źródłaSouth, Kaylee. "Improving abiotic and biotic stress tolerance in floriculture crops". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595499762154056.
Pełny tekst źródłaKomisar, Simeon J. "Biotic and abiotic transformations of tetrachloromethane in methanogenic environments /". Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/10111.
Pełny tekst źródłaBewell, Michael Anthony. "Mechanisms of calcium homeostasis at higher plant endomembranes". Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310915.
Pełny tekst źródłaWhite, Peter. "The effects of biotic and abiotic forces on species richness". Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104714.
Pełny tekst źródłaLes communautés forestières qui habitent les parcelles de forêts qui subsistent aujourd'hui sont affectées par les perturbations ainsi que par la qualité de l'habitat que leur procure les plantes-hôtes. Ces deux phénomènes ont un impact particulièrement important dans les paysages modifiés par l'activité humaine. Développer une meilleure compréhension de ces phénomènes va faciliter la prise de décision et les efforts de conservations visant à préserver et protéger la biodiversité des forêts. L'objectif global de cette thèse est d'étudier les divers aspects reliés à la qualité de l'habitat dans les parcelles forestières des collines montérégiennes du sud-est du Québec, Canada. J'utilise des techniques en système d'information géographique pour déterminer l'impact d'une perturbation naturelle épisodique (tempête de verglas) ainsi qu'une perturbation anthropogénique chronique (sentiers récréationnels) sur la qualité des habitats forestiers (Chapitre 1) et un assemblage de chenilles vivant en forêt (Chapitre 2). J'ai démontré que les dégâts engendrés par les tempêtes de verglas sont distribués de façon hétérogène à travers le paysage forestier, différant selon le type de débris ligneux grossiers examiné. Ces différents types de débris ligneux grossiers servent d'habitat à divers groupes taxonomiques. J'ai découvert que les perturbations anthropogéniques, au contraire des perturbations naturelles, n'ont pas eu d'impacts positifs sur les assemblages de chenilles vivants en forêt. J'ai également exploré le concept de qualité d'habitat en considérant l'identité de la plante hôte (Chapitre 3) et la qualité foliaire à l'échelle du quadrat (Chapitre 4). J'ai découvert que l'assemblage de chenille démontre des préférences marquées pour certaines plantes hôtes et que ces préférences peuvent dépendre de différentes qualités foliaires à l'échelle du quadrat à différentes périodes durant la saison de croissance. Cette thèse contribue à la documentation croissante sur les facteurs qui affectent la richesse spécifique des communautés d'insectes vivant dans les forêts des paysages perturbés. De plus, cette thèse propose plusieurs outils spécifiques à la gestion pour évaluer les perturbations en milieu forestier et donne un aperçu de l'impact que peut avoir la sélection de différentes espèces d'arbres sur les communautés forestières lors de l'élaboration d'initiatives de plantation d'arbres.
Versteegen, Audrey. "Biotic and abiotic controls on calcium carbonate formation in soils". Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/5332.
Pełny tekst źródłaAlzwiy, Ibrahim A. Mohamed. "The interaction between abiotic and biotic stress in Arabidopsis thaliana". Thesis, University of Exeter, 2013. http://hdl.handle.net/10871/13946.
Pełny tekst źródłaMueller, Moritz. "Biotic and abiotic alteration of hydrothermal sulphides at the seafloor". Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/69029/.
Pełny tekst źródłaPham, Jasmine. "The role of AHK5 in abiotic and biotic stress signalling". Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/8959.
Pełny tekst źródłaChemayek, Bosco. "Studies on Resistance to Biotic and Abiotic Stresses in Wheat". Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15362.
Pełny tekst źródłaEndeshaw, Solomon Tadesse. "Grape and olive: physiological responses to biotic and abiotic stress". Doctoral thesis, Università Politecnica delle Marche, 2013. http://hdl.handle.net/11566/242716.
Pełny tekst źródłaPlants grow and develop in an open field, with continuously changing weather condition that induces stress. Stress are broadly classified as external and internal. Internal stress is that drive from mutation or abnormal cell divisions and to unbalanced growth and carbon allocation and partitioning. External stress can have abiotic and biotic origin. Drought, cold, high-salinity, heat and phytotoxin released from undecomposed litter and manure are major abiotic stresses that severely reduce the plant growth, development and yield. Whereas, pathogen (bacteria, fungi, phytoplasma, virus) are the major biotic stress that severely reduce yield. To meet the current increase in global demand of agricultural good in general and olive oil and wine in particular, each growing region has to respond either by incorporating new olive and grape orchard in the existing agroecological zone and/or expanding to new agroecological zones or by changing mode of cultivation and orchard management, facing different biotic stress and external stress in replanting condition. This project aimed at evaluating the physiological responses of grape and olive to biotic and abiotic stress respectively. In particular, effect of Bios noir (BN, a phytoplama disease) and grapevine leafroll associated virus 3 (GLRaV-3, viral disease) on gas exchange and yield of Vitis vinifera cv. Chardonnay and Cabernet Franc respectively; and effect of undecomposed olive shoot residue (OSR, originated from pruning and leaf shedding) and fresh two-phase olive mill waste (TPOMW, coming from two-phase decanter) were studied on shoot growth, root proliferation and biomass partition of Olea eropaea L. cv. Arbequina and Frantoio. Biotic stress originated from BN and GLRAV-3 infection showed that Photosynthesis, stomatal conductance and transpiration were significantly reduced in the symptomatic Chardonnay and Cabernet Franc vines through the summer after the fruit set. The reduction in metabolism due to BN and GLRaV-3 infection in cv. Chardonnay and Cabernet Franc had a direct influence on the decrease in total berry production, vine size and cane lignifications of symptomativ vines. Indeed, they suffered a drastic decrease of about 70 and 40% in yield respectively. Whereas, application of OSR and TPOMW in the pot altered shoot and root growth, biomass partition and relative growth rate of fine root and shoot; while increasing soil total organic matter and carbon, total N and polyphenol content of the growing substrate. Hence there is no chemical spray develop to control the infection of BN and GLRaV-3 pathogens, planting phytoplasma and virus free root stocks during the vineyard establishment and uprooting the infected vine and replanting new to avoid spread during pruning and by insect vectors is the best way to minimize the adverse effect of BN and GLRaV-3 on quality and quantity yield. To avoid antagonistic effect of OSR and TPOMW on root and shoot growth and improve soil fertility knowing the exact quantity, for each types olive orchards, and when to apply in play major role.
Jones, Lisa. "The role of biotic and abiotic factors in exotic species replacement". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114198.
Pełny tekst źródłaLes invasions biologiques sont une composante majeure des changements environnementaux au niveau mondiale et leurs fréquences continuent à augmenter. La plupart des études sur l'impact des invasions à l'échelle communautaire s'intéressent principalement aux interactions entre les espèces exotiques et indigènes. Par contre, on observe de plus en plus des interactions entre des espèces exotiques, ce qui pourrait modifier leurs impacts respectifs sur les écosystèmes envahis. Cette recherche a pour but d'examiner le 'remplacement d'espèces exotiques', un phénomène par lequel l'abondance d'une espèce exotique nouvellement arrivée surpasse l'abondance d'une espèce exotique déjà présente et dominante, qui possède également une similarité fonctionnelle. Ce phénomène est exploré ici à l'aide de deux bivalves Eurasiennes de la famille des Dreissenidés qui ont envahi le fleuve Saint-Laurent au début des années 1990, la moule zébrée (Dreissena polymorpha) et la moule quagga (D. bugensis). J'examine le schéma général de remplacement de la moule zébrée par son congénère dans un canal de navigation relié au fleuve. J'examine également les facteurs environnementaux et les traits d'histoire de vie de ces moules qui peuvent influencer se remplacement. Depuis les années 1990, la moule quagga a remplacé la moule zébrée en tant que le dreissenidé dominant. Par contre, la distribution et l'abondance contemporaines des adultes sont structurées de façon spatiale: les moules quagga dominent la zone profonde, tandis que les moules zébrées demeurent communes dans la région peu profonde du canal. Des études sur le terrain et des expériences in situ ont été utilisées pour examiner l'importance relative des processus de pré-établissement, d'établissement et de post-établissement, sur la distribution et l'abondance des moules adultes. Malgré l'importance potentielle de l'approvisionnement et du comportement larvaire, y compris la sélection du substrat durant l'établissement, aucun de ces processus ne joue un rôle important dans la détermination de l'abondance et la distribution des dreissenidés adultes. Plutôt, les principaux facteurs déterminants étaient les processus de post-recrutement impliquant la compétition mediée par l'environnement. En générale, la condition, la croissance, la longueur de coquille et la survie des moules zébrées adultes étaient inférieures à celles des moules quagga, et ces différences étaient plus prononcées dans la zone profonde du canal. Cette étude met en valeur l'importance des différences subtiles des traits d'histoire de vie et des tolérances abiotiques d'espèces étroitement liées dans la compréhension des schémas changeants de distribution et d'abondance d'individus dans les communautés envahies.
Spliethoff, Henry Matthew. "Biotic and abiotic transformations of arsenic in the Upper Mystic Lake". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11816.
Pełny tekst źródłaIncludes bibliographical references (leaves 63-65).
by Henry Matthew Spliethoff.
M.S.
Ohneck, Emily Jean. "Interaction of Acinetobacter baumannii with abiotic and biotic environments". Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami147937747636766.
Pełny tekst źródłaGessese, Mesfin Kebede. "Characterization of wheat landraces for resistance to biotic and abiotic stresses". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17198.
Pełny tekst źródłaLancioni, Pietro <1980>. "Studies on biotic and abiotic elicitors inducing defense responses in tomato". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1980/1/PIETRO_LANCIONI_TESI_.pdf.
Pełny tekst źródłaLancioni, Pietro <1980>. "Studies on biotic and abiotic elicitors inducing defense responses in tomato". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1980/.
Pełny tekst źródłaSrinivas, D. "De novo designed foldamers based on biotic and abiotic building blocks". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2008. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2653.
Pełny tekst źródłaDutta, Sampa. "Abiotic and biotic stress response of tea plants and their biochemical characterization". Thesis, University of North Bengal, 2000. http://hdl.handle.net/123456789/878.
Pełny tekst źródłaUrbina, Barreto Ifigenia. "Abiotic and biotic factors determining the nutrient stoichiometry of contrasting terrestrial ecosystems". Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667763.
Pełny tekst źródłaEverything on Earth is based on chemistry. This statement has profound implications for ecological interactions. Living organisms generate and control fluxes of energy and matter among the atmosphere, lithosphere and the hydrosphere, shaping the chemistry of the Earth in many different ways. Ecological stoichiometry aims to explore the balance and role of multiple chemical elements in ecological interactions and help us to understand patterns and processes in nature. It represents the link between the biogeochemistry and the ecosystems’ function and allows to describe processes across different levels of biological organization, from cellular structures to ecosystems. In this Thesis I use ecological stoichiometry to describe processes at organism and ecosystem levels in three contrasting terrestrial environment conditions. Autotrophs’ stoichiometry is established when these organism use light to fix carbon (C) and simultaneously assimilate nutrients. Plants are able to store nutrients in the cells’ vacuole and in different organs, which make them highly flexible (less homeostatic) in terms of their elemental composition. This feature explains the high adaptability of plants to different environments, including soil nutrient limitation conditions. Furthermore, plant-soil interaction could be explored through the foliar stoichiometry, because it has been shown that the foliar N:P is positive correlated with the N:P of soil in all terrestrial ecosystem, suggesting that foliar stoichiometry is a good indicator of the resource availability. Plant adaptations to soil nutrient limiting conditions are quite common in all terrestrial ecosystems, such as nitrogen fixation, mycorrhiza association, production of phosphatases and nutrient resorption before leave abscission. The species’ chemical composition is affected by all these abiotic and biotic interactions, and these exchange of chemical elements between the species and the abiotic part of the system determine the elemental composition of different components of the ecosystems. In Chapter 2, we explore the biotic effect of the community composition on the species foliar stoichiometry, taken as a proxy of the species’ biogeochemical niche. We found that each species has its own biogeochemical niche and is able to readjust its chemical composition in response to different biotic conditions. We conclude that plants can readjust their foliar element composition when they grow in communities with contrasting plant composition through the biogeochemical niche displacement, suggesting a differential use of the resources when the patterns of species coexistence change. In Chapter 3 we explore the plant-soil stoichiometry changes due the shrub expansion into the subalpine grassland in the Pyrenees. Shrub expansion had a clear impact on the plant-soil stoichiometry spectrum. This expansion represents the transition from pure grassland to shrubland. The grassland is an ecosystem dominated by short-lived species, fast nutrient turnover between the plant-soil compartments, high nitrogen (N), phosphorus (P) and potassium (K) concentrations in the plant-soil system, high productivity but low biomass stocks. The shrubland is an ecosystem characterized by long-lived species with more conservative strategy, slow nutrient turnover (low N and P concentrations in the plant-soil compartments, high C:nutrient ratios in the aboveground biomass) and high stocks of C and nutrients in the plant aboveground biomass. Shrub encroachment increase the acquisition of N through mycorrhizal associations. The changes in storage and elemental composition of the plant soil system along the succession from grassland to shrubland suggests that there is a slowdown of the biogeochemical cycle in the subalpine mountain areas where shrub encroachment occurred. In the Chapter 4, we describe the distribution of C and the most important nutrients for the plant development (N, P, K) in the plant and soil compartments in old-growth tropical forests growing in nutrient-poor soil in French Guiana. We also studied the nutrient resorption from senescent leaves, a poorly explored mechanism that plants use to avoid losing nutrients in this ecosystem. Our results showed that P was the scarcest nutrient in the leaf, leaf-litter and soil. Resorption efficiencies were higher for K and P than for N, and only K resorption efficiency was affected by seasonality. P resorption showed a negative and weak correlation with P in soil (total and available). Relationships between nutrient resorption and species functional characteristics (growth rate, wood density, diameter at breast height and specific leaf area) were weak and varied among the nutrients, and phylogenetic relatedness did not account for the variability in resorption efficiencies. Our results suggest that high K and P resorption from senescent leaves is an adaptive strategy allowing species to cope with soil nutrient scarcity. Furthermore, the level of nutrient immobilization in foliar compounds (N > P > K) seem to significantly determine the resorption process. We conclude that nutrient resorption from senescent leaves is a key process for plants to conserve nutrients in tropical forests of French Guiana, especially for K and P, where soil availabilities are low and depend mainly on soil parent material and leaching process. To sum up, in this Thesis we have demostrated how the elemental composition of the plant-soil system reflects ecological interactions and processes, such as intra and inter specific plant interactions (Chapter 2), poorly explored physiological processes such as nutrient resorption (Chapter 4) and the importance of stoichiometry studies for describing changes at ecosystem level and predicting future scenarios (Chapter 3). These studies add new knowledge to the ecological stoichiometry field and highlights the importance of this approach in the ecological studies.
Duc, Nguyen Thanh. "Abiotic and biotic methane dynamics in relation to the origin of life". Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-65895.
Pełny tekst źródłaAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Submitted.
Bellingan, Terence Andrew. "Biotic and abiotic drivers of macroinvertebrate assemblages in a South African river". Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/61839.
Pełny tekst źródłaTaylor, J. P. "Abiotic and biotic influences on acetochlor fate in pristine soils and subsoils". Thesis, University of Kent, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270820.
Pełny tekst źródłaImeh-Nathaniel, Adebobola. "Evolutionary Ecology of Arabidopsis thaliana: Interactions with Biotic and Abiotic Environmental Factors". Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1351039606.
Pełny tekst źródłaBarron, Harley. "Infection of Paulownia by Alternaria and influence of abiotic and biotic factors". Thesis, Barron, Harley (2003) Infection of Paulownia by Alternaria and influence of abiotic and biotic factors. Honours thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/32748/.
Pełny tekst źródłaMarshall, Jill. "Lithologic, Climatic, and Biotic vs. Abiotic Controls on Erosion and Landscape Evolution". Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19291.
Pełny tekst źródłaCondorelli, Giuseppe Emanuele <1987>. "Genetic dissection of resistance to abiotic and biotic stresses in durum wheat". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amsdottorato.unibo.it/9223/1/Condorelli_Giuseppe%20Emanuele_tesi.pdf.
Pełny tekst źródłaFalkenberg, Nyland Ray. "Remote sensing for site-specific management of biotic and abiotic stress in cotton". Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/478.
Pełny tekst źródłaGworek, Jennifer R. "Interacting abiotic and biotic factors affecting Jeffrey pine regeneration along an elevational gradient". abstract and full text PDF (free order & download UNR users only), 2005. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1433401.
Pełny tekst źródłaGunina, Anna. "Biotic and abiotic control of microbial community structure and activity in forest soils". Doctoral thesis, Bangor University, 2017. http://hdl.handle.net/11858/00-1735-0000-002E-E453-7.
Pełny tekst źródłaWade, James Patrick. "Biotic and Abiotic Remediation of Acetaminophen with Woodchip and Biochar-amended Woodchip Adsorbents". Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/64157.
Pełny tekst źródłaMaster of Science
Nakamura, Masahiro. "Positive plant-mediated indirect effects of biotic and abiotic factors on arthropod communities". 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147855.
Pełny tekst źródłaWeltzin, Jake Frederick 1964. "Biotic and abiotic constraints on shifts in temperate savanna ecotones at lower treeline". Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/288779.
Pełny tekst źródłaMott, Cy Larue. "Biotic and abiotic influences on aggressive interactions within larval Ambystoma assemblages". OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/140.
Pełny tekst źródłaFarré, Armengol Gerard. "Biotic and abiotic factors that determine the emission of volatile organic compounds by flowers". Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/288049.
Pełny tekst źródłaFlowers emit volatile organic compounds (VOCs) to attract pollinators and stimulate reproductive outcrossing. Some floral volatiles can play roles other than attraction, such as defense against herbivores. This duality of roles of flower emissions converts floral scents into complex mixtures of compounds with multiple effects on different organisms. The complexity of understanding and characterising floral emissions increases when considering that they are variable in time and space. To all these sources of variability we can add diverse biotic and abiotic environmental factors that modify floral VOC emissions in many different ways. The main objective of this thesis was to shed light on which are the factors that determine floral volatile emissions, and how do they affect these emissions and their ecological functions. In the first chapter of this thesis we reviewed the current knowledge on floral VOC emissions. We identified the open questions that still needed to be addressed or investigated in more detail in the research field of floral VOC emissions. Floral emissions are first determined by the array of compounds that the species are able to produce and their potential biosynthetic and emission capacities, which are strongly related to the species biology. We tested and demonstrated that flowering plants pollinated by insects usually present higher diversities of floral volatiles and emit higher amounts of them, than do plants pollinated by wind which do not need floral volatiles for attractive purposes. We tested whether well-known seasonal patterns of decreasing competition occurring every year in a community among co-flowering plants for pollinators led to the selection of a pattern of decreasing emission of floral volatiles and decreasing production of floral rewards along the flowering period of each species. We also observed that plants adapt their physiology to optimize their floral emissions under the climatic conditions of the flowering period. Floral VOC emissions of the species are affected by environmental factors at the individual (organism) or tissular level. There are diverse physiological states of the plant that can substantially modify the emission profiles and amounts of floral VOCs. Our experiments demonstrated that floral microbiota can play a crucial role in the quantity and quality of floral VOC emissions. We also showed that flower herbivory by Pieris brassicae caterpillars on Diplotaxis erucoides plants induced immediate increases in floral emission rates of few compounds with known defensive functions. Leaf herbivory caused no changes in the emissions of intact flowers, but the combination of leaf herbivory with flower herbivory showed a synergistic effect with enhanced defensive response. The research on the potential changes that floral emissions could experience in response to diverse drivers of Global Change are of critical interest because of the diverse effects that such changes can have on the interactions that floral VOCs mediate. Our results revealed that temperature increases as those predicted for the next century as a result of Global Warming can lead to significant total increases in floral VOC emissions and also to important changes in floral scent relative composition. We also detected that ozone caused significant degradation of floral compounds and changes in their relative composition. Behavioural tests indicated that all the changes observed in floral chemical cues when exposed to ozone resulted in the loss of attraction effect on pollinators. This thesis thus provides new insights on the factors that determine floral volatile emissions and their repercussions on plant-pollinator interactions and warrant deep consideration of both biotic and abiotic factors driving floral scent chemistry and floral scent ecology in a continuously changing environment.
Murphy, Meaghan Thibault. "Biotic and abiotic controls on soil respiration in a biodiversity plantation in the tropics". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97978.
Pełny tekst źródłaLeitão, Susana T. "Unravelling the genetic control of combined biotic/abiotic stress resistance in Phaseolus vulgaris L". Doctoral thesis, Universidade Nova de Lisboa, Instituto de Tecnologia Química e Biológica António Xavier, 2020. http://hdl.handle.net/10362/95339.
Pełny tekst źródła"Common bean (Phaseolus vulgaris L.) is among the most important grain legumes for human consumption worldwide. Portugal has a promising common bean germplasm that resulted from more than five centuries of natural adaptation and farmers’ selection. Nevertheless, limited characterization of this resource hampers its exploitation by breeding programs. To support a more efficient conservation of the national bean germplasm and promote its use in crop improvement, we performed, for the first time, a simultaneous molecular marker and seed and plant morphological characterization of 175 accessions collected from Portuguese mainland and islands traditional bean-growing regions. Most of the Portuguese accessions grouped with the race representatives and wild relatives from the Andean region."
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Burcher, Chris L. "Biotic and abiotic responses to rural development and legacy agriculture by southern Appalachain streams". Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27438.
Pełny tekst źródłaPh. D.
Ryerson, William G. "The role of abiotic and biotic factors in suspension feeding mechanics of Xenopus tadpoles". [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002790.
Pełny tekst źródłaClark, Jennifer M. "Abiotic and biotic factors affecting size-dependent crayfish (Orconectes obscurus) distribution, density, and survival". [Kent, Ohio] : Kent State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1239497384.
Pełny tekst źródłaTitle from PDF t.p. (viewed Nov. 16, 2009). Advisor: Mark Kershner. Keywords: crayfish; stream; predation; current velocity; water depth; grain size; resource competition. Includes bibliographical references.
Preiner, Martina [Verfasser], William [Gutachter] Martin i Michael [Gutachter] Schmitt. "The abiotic pattern of biotic CO2 fixation / Martina Preiner ; Gutachter: William Martin, Michael Schmitt". Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2020. http://d-nb.info/1206414278/34.
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