Bibliographies thématiques / Abiotic and biotic variables

Littérature scientifique sur le sujet « Abiotic and biotic variables »

Auteur : Grafiati
Publié le 10 mars 2023

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Articles de revues sur le sujet "Abiotic and biotic variables"

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McNab, W. Henry, et Tara L. Keyser. « A vegetative index of stand productivity based on tree inventory for predicting oak site index in the Central Hardwood Region ». Canadian Journal of Forest Research 50, no 8 (août 2020) : 760–73. http://dx.doi.org/10.1139/cjfr-2019-0412.

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Models for prediction of site index (SI) typically include only abiotic causal variables (e.g., soil) and lack biotic response variables (e.g., vegetation), which could exhibit greater sensitivity to important environmental factors affecting tree height growth. Our study objective was to evaluate Whittaker’s moisture condition index (MCI) (R.H. Whittaker. 1956. Ecol. Monogr. 26: 1–80) as a potential biotic variable for inclusion with conventional abiotic variables in oak (Quercus L.) SI prediction models. The MCI is the sum of relative abundances of inventoried plot tree species weighted by their moisture affinity classification. We compared regression parameters of conventional base models including only abiotic variables with exploratory models configured with abiotic variables and MCI for explaining variation of SI. The best abiotic model included only aspect. When MCI was included in the abiotic model, aspect became insignificant, resulting in a single-variable biotic model that accounted for increased SI variation. The MCI biotic model remained significant when tested with independent data from a distant location. The MCI is easily calculated using plot inventory data, and with further evaluation, it may be confirmed as a useful biotic variable in combination with abiotic soil and topographic variables for prediction of oak SI.
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Aryanti, Nirmala Ayu, Febri Arif Cahyo Wibowo, Mahidi Mahidi, Frita Kusuma Wardhani et I. Komang Tri Wijaya Kusuma. « Hubungan Faktor Biotik dan Abiotik Terhadap Keanekaragaman Makrobentos di Hutan Mangrove Kabupaten Lombok Barat ». Jurnal Kelautan Tropis 24, no 2 (19 mai 2021) : 185–94. http://dx.doi.org/10.14710/jkt.v24i2.10044.

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High human activity around the coastal area will affect the mangrove ecosystem and the biota such as macrobenthos. Benthic diversity can reflect conditions of mangrove ecosystem, that slow growth and sensitive to environmental changes. This study aims to determine the influence of biotic and abiotic environments on the macrobenthos in Cendi Manik Village, Sekotong District, West Lombok Regency, West Nusa Tenggara. Data collection of macrobenthos, biotic and abiotic environments in natural and rehabilitation mangrove, then the diversity species of macrobenthos with biotic and abiotic environmental variables were analyzed multiple regression. The most dominant vegetations are Rhizophora mucronata Lam and Avicennia marina Forssk. The diversity index for macrobenthos is low (H’ 1,207) in natural and rehabilitation mangrove. Macrobenthos between two location have high similarity with 84,6%. The result of multiple regression test showed that most influencing of macrobenthos were mud thickness and brightness. Aktivitas manusia yang tinggi sekitar kawasan pesisir akan mempengaruhi ekosistem mangrove dan biota di dalamnya seperti makrobentos. Keanekaragaman bentos dapat mampu mencerminkan kondisi ekosistem mangrove, pertumbuhan yang lambat dan sensitif terhadap perubahan lingkungan. Penelitian ini bertujuan untuk mengetahui hubungan lingkungan biotik dan abiotik terhadap makrobentos yang ada di Desa Cendi Manik Kecamatan Sekotong Kabupaten Lombok Barat Nusa Tenggara Barat. Pengumpulan data makrobentos, biotik dan abiotik lingkungan pada hutan mangrove alam dan rehabilitasi, kemudian keanekaragaman jenis makrobentos dengan variabel lingkungan biotik dan abiotik dianalisis regresi berganda. Jenis vegetasi yang paling mendominasi adalah jenis Rhizophora mucronata Lam dan Avicennia marina Forssk. Keanekaragaman jenis makrobentos termasuk dalam kategori rendah (H’ 1,207) di hutan mangrove alam dan rehabilitasi. Jenis makrobentos antara dua lokasi tersebut memiliki kemiripan yang tinggi yaitu 84,6 %. Uji regresi berganda diperoleh variabel lingkungan yang paling berpengaruh pada keanekaragaman jenis makrobentos adalah ketebalan lumpur dan kedalaman kecerahan air.
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De Araújo Lira, André Felipe, Stênio Ítalo Araújo Foerster, Adriano Medeiros DeSouza et Luis F. De Armas. « Disentangling diversity patterns in Cuban scorpions (Arachnida : Scorpiones) ». Novitates Caribaea, no 19 (17 janvier 2022) : 72–91. http://dx.doi.org/10.33800/nc.vi19.290.

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The assembly of communities is often viewed as a process involving the dispersal of species from a regional pool. An oceanic island provides a unique opportunity to test such a hypothesis and many others related to the patterns and processes behind biodiversity. Our aim was to investigate the patterns of scorpion diversity in the Cuban archipelago, using biotic and abiotic variables and their interactions as explanatory features. We use biotic and abiotic variables related to vegetation, climate and topography characterize the landscape of the Cuban archipelago. In this way, we analyze the patterns of beta diversity of the scorpions, verifying the effects of the variables alone and together. Scorpion fauna of the Cuban archipelago comprises 61 species, grouped into nine genera and two families: Buthidae and Diplocentridae. The interplay between biotic and abiotic variables explained scorpion species composition, especially when spatial predictors were considered. Climatic and spatial predictors affected scorpion beta diversity in terms of richness difference. These patterns are discussed emphasizing the role of biotic and abiotic environmental features and their interactions on the mechanisms of scorpion biodiversity generation and maintenance in Cuban archipelago.
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Bennington, S., W. Rayment et S. Dawson. « Putting prey into the picture : improvements to species distribution models for bottlenose dolphins in Doubtful Sound, New Zealand ». Marine Ecology Progress Series 653 (29 octobre 2020) : 191–204. http://dx.doi.org/10.3354/meps13492.

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Species distribution models (SDMs) often rely on abiotic variables as proxies for biotic relationships. This means that important biotic relationships may be missed, creating ambiguity in our understanding of the drivers of habitat use. These problems are especially relevant for populations of predators, as their habitat use is likely to be strongly influenced by the distribution of their prey. We investigated habitat use of a population of a top predator, bottlenose dolphins Tursiops truncatus, in Doubtful Sound, New Zealand, using generalised additive models, and compared the results of models with and without biotic predictor variables. We found that although habitat use by bottlenose dolphins was significantly correlated with abiotic variables that likely describe foraging areas, introduction of biotic variables describing potential prey almost doubled the deviance explained, from 19.8 to 39.1%. Biotic variables were the most important of the predictors used, and indicated that the dolphins showed a preference for areas with a high abundance of a reef fish, girdled wrasse Notolabrus cinctus. For the dolphins of Doubtful Sound, these results show the importance of prey distribution in driving habitat use. On a broader scale, our results indicate that making an effort to include true biotic descriptors in SDMs can improve model performance, resulting in better understanding of the drivers of distribution of marine predators.
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Ghini, Raquel, et Marcelo Augusto Boechat Morandi. « Biotic and abiotic factors associated with soil suppressiveness to Rhizoctonia solani ». Scientia Agricola 63, no 2 (avril 2006) : 153–60. http://dx.doi.org/10.1590/s0103-90162006000200007.

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Crop management may modify soil characteristics, and as a consequence, alter incidence of diseases caused by soilborne pathogens. This study evaluated the suppressiveness to R. solani in 59 soil samples from a microbasin. Soil sampling areas included undisturbed forest, pasture and fallow ground areas, annual crops, perennial crops, and ploughed soil. The soil samples were characterized according to abiotic variables (pH; electrical conductivity; organic matter content; N total; P; K; Ca; Mg; Al; H; S; Na; Fe; Mn; Cu; Zn; B; cation exchange capacity; sum of bases and base saturation) and biotic variables (total microbial activity evaluated by the CO2 evolution and fluorescein diacetate hydrolysis; culturable bacterial, fungal, actinomycetes, protozoa, fluorescent Pseudomonas and Fusarium spp. communities). The contribution and relationships of these variables to suppression to R. solani were assessed by path analysis. When all samples were analyzed together, only abiotic variables correlated with suppression of R. solani, but the entire set of variables explained only 51% of the total variation. However, when samples were grouped and analyzed by vegetation cover, the set of evaluated variables in all cases accounted for more than 90% of the variation in suppression of the pathogen. In highly suppressive soils of forest and pasture/fallow ground areas, several abiotic variables and fluorescein diacetate hydrolysis correlated with suppression of R. solani and the set of variables explained more than 98% of suppressiveness.
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Piana, Pitágoras Augusto, Luiz Carlos Gomes et Elimaida Mayo Cortez. « Factors influencing Serrapinnus notomelas (Characiformes : Characidae) populations in upper Paraná river floodplain lagoons ». Neotropical Ichthyology 4, no 1 (mars 2006) : 81–86. http://dx.doi.org/10.1590/s1679-62252006000100008.

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Identification of variables that influence fish populations is one of the main challenges in ecology. To explore this, data were collected quarterly from February 2000 to November 2001 using seines, along the shore of four isolated lagoons of the upper Paraná River floodplain. Serrapinnus notomelas was selected to assess the effect of abiotic and biotic variables using indirect gradient analysis. Abiotic variables were summarized by principal components analysis (PCA) and then the scores of the axis retained for interpretation were correlated with abundances of S. notomelas. Variables that best explained S. notomelas abundance were surface area of the lagoon, total suspended solids and Secchi depth (these last two, indirectly linked to predation). The most relevant biotic variable that determined population size of S. notomelas was predation.
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ANDERSON, T. K., et M. V. K. SUKHDEO. « Abiotic versus biotic hierarchies in the assembly of parasite populations ». Parasitology 137, no 4 (22 décembre 2009) : 743–54. http://dx.doi.org/10.1017/s0031182009991430.

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SUMMARYThe presence or absence of parasites within host populations is the result of a complex of factors, both biotic and abiotic. This study uses a non-parametric classification tree approach to evaluate the relative importance of key abiotic and biotic drivers controlling the presence/absence of parasites with complex life cycles in a sentinel, the common killifish Fundulus heteroclitus. Parasite communities were classified from 480 individuals representing 15 fish from 4 distinct marsh sites in each of 4 consecutive seasons between 2006 and 2007. Abiotic parameters were recorded at continuous water monitoring stations located at each of the 4 sites. Classification trees identified the presence of benthic invertebrate species (Gammarus sp. and Littorina sp.) as the most important variables in determining parasite presence: secondary splitters were dominated by abiotic variables including conductance, pH and temperature. Seventy percent of hosts were successfully classified into the correct category (infected/uninfected) based on only these criteria. The presence of competent definitive hosts was not considered to be an important explanatory variable. These data suggest that the most important determinant of the presence of these parasite populations in the common killifish is the availability of diverse communities of benthic invertebrates.
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Simões, Marianna V. P., et A. Townsend Peterson. « Importance of biotic predictors in estimation of potential invasive areas : the example of the tortoise beetleEurypedus nigrosignatus, in Hispaniola ». PeerJ 6 (5 décembre 2018) : e6052. http://dx.doi.org/10.7717/peerj.6052.

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Climatic variables have been the main predictors employed in ecological niche modeling and species distribution modeling, although biotic interactions are known to affect species’ spatial distributions via mechanisms such as predation, competition, and mutualism. Biotic interactions can affect species’ responses to abiotic environmental changes differently along environmental gradients, and abiotic environmental changes can likewise influence the nature of biotic interactions. Understanding whether and how to integrate variables at different scales in ecological niche models is essential to better estimate spatial distributions of species on macroecological scales and their responses to change. We report the leaf beetleEurypedus nigrosignatusas an alien species in the Dominican Republic and investigate whether biotic factors played a meaningful role in the distributional expansion of the species into the Caribbean. We evaluate ecological niche models built with an additive gradient of unlinked biotic predictors—host plants, using likelihood-based model evaluation criteria (Akaike information criterion and Bayesian information criterion) within a range of regularization multiplier parameter values. Our results support the argument that ecological niche models should be more inclusive, as selected biotic predictors can improve the performance of models, despite the increased model complexity, and show that biotic interactions matter at macroecological scales. Moreover, we provide an alternative approach to select optimal combination of relevant variables, to improve estimation of potential invasive areas using global minimum model likelihood scores.
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Meier, Eliane S., Felix Kienast, Peter B. Pearman, Jens-Christian Svenning, Wilfried Thuiller, Miguel B. Araújo, Antoine Guisan et Niklaus E. Zimmermann. « Biotic and abiotic variables show little redundancy in explaining tree species distributions ». Ecography 33, no 6 (12 novembre 2010) : 1038–48. http://dx.doi.org/10.1111/j.1600-0587.2010.06229.x.

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Borzée, Amaël, Ye Inn Kim, Zoljargal Purevdorj, Irina Maslova, Natalya Schepina et Yikweon Jang. « Relationship between anuran larvae occurrence and aquatic environment in septentrional east Palearctic landscapes ». Herpetozoa 34 (14 décembre 2021) : 265–70. http://dx.doi.org/10.3897/herpetozoa.34.e68577.

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The presence of amphibian larvae is restricted by both biotic and abiotic variables of the environment. Some of these variables are still undetermined in the septentrional eastern Palearctic where Rana amurensis, Strauchbufo raddei and Dryophytes japonicus are found in large numbers. In this study, we sampled 92 sites across Mongolia, Russia and the Democratic People’s Republic of Korea and measured biotic and abiotic water variables, as well as the height of flooded terrestrial and emergent aquatic vegetation at the breeding site. We determined that the presence of anuran larvae is generally, but not always, linked to pH and temperature. Rana amurensis was not significantly affected by any of the variables measured, while S. raddei was impacted by water conductivity and D. japonicus by pH, temperature and vegetation. Our results highlight a potential risk for these species due to the changes in aquatic variables in response to desertification.
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Thèses sur le sujet "Abiotic and biotic variables"

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Hegeman, Ericka E. « Modeling freshwater mussel distribution in relation to biotic and abiotic habitat variables in the Middle Fork John Day River, Oregon ». DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1274.

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The habitat requirements of western freshwater mussels, Anodonta, Gonidea, and Margaritifera, remain unclear despite their imperiled status. Freshwater mussels provide a series of ecosystem services including habitat enhancement, substratum stabilization, nutrient cycling, and water clarification, which makes their loss from aquatic ecosystems particularly detrimental. To improve the efficacy of restoration actions targeting these organisms, I used random forest modeling to investigate the biotic and abiotic factors influencing mussel density and distribution throughout a 55-kilometer (km) segment of the Middle Fork John Day River (MFJDR), in northeastern Oregon. Data was collected to characterize the occurrence of mussels with respect to the hierarchical, hydrogeomorphic structure of habitat within reaches of varying valley confinement and channel units nested within these reaches. Data regarding functional habitat features were also included to ensure that models included the wide range of characteristics that mussels need from their environment. By collecting data at both the reach and channel unit scale, I was able to investigate how mussel densities and distributions vary with spatial scale and other biophysical parameters. Throughout the study area, Margaritifera density exhibited a unimodal distribution with respect to river km, while Anodonta and Gonidea density showed a negative relationship with river km and exhibited higher densities downstream. The large scale, longitudinal trends of Margaritifera were related to hydrogeomorphic characteristics at the reach scale, while less than half of the longitudinal variation in Anodonta and Gonidea were explained by hydrogeomorphic and water quality parameters. At the channel unit scale, all mussel genera responded to the patchy variation in physical habitat characteristics, particularly habitat factors that indicated more stable parts of the channel. Overall, physical habitat characteristics such as woody debris, emergent aquatic vegetation, coarse substratum, and channel morphology were more important than hydraulic, biotic, and chemical variables. These results suggest that at both the reach and channel unit scales, mussel density and distribution are influenced by high flow refugia and the hierarchical structuring of hydrogeomorphic habitat characteristics. These results will assist mussel restoration efforts by providing specific guidance about the types of physical habitat conditions that are suitable for mussels.
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Croft, Amy A. « Assessing Plant Community Structure in the Upper Las Vegas Wash Conservation Transfer Area, Nevada : The Influence of Biotic and Abiotic Variables ». DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/5005.

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Ecological communities are complex, the structure of which is composed of interactions between multiple community characteristics and the abiotic and biotic factors shaping them. Because of this complexity, ecological studies are generally limited in scope and size, often dissecting communities into their component parts to examine them piece by piece. While this might be the most practical method to study communities, this approach often neglects other characteristics that, with their inclusion, would provide a more complete picture of community ecology. The studies described in this dissertation were conducted in an effort to synthesize the complexity that is inherent in ecological plant communities growing on a Mojave Desert bajada. Each study addresses a separate component of community structure, which, taken as a whole, provides a more thorough understanding of arid plant community dynamics. Overall, our results reveal the importance of substrate variables and their role in shaping plant community structure in arid environments. In addition, these investigations provide evidence of the strong role that facilitation plays on this bajada and possibly arid plant communities as a whole. The comprehensive approach described in this dissertation will enable ecologists to gain a more complete understanding of community dynamics and apply this knowledge to various climate change and land management scenarios.
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Rickert, Esther [Verfasser]. « Seasonally fluctuating fouling control of Fucus vesiculosus and Fucus serratus from the Baltic Sea : is fouling control linked to abiotic and biotic variables ? / Esther Rickert ». Kiel : Universitätsbibliothek Kiel, 2015. http://d-nb.info/1080521615/34.

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Scherer, Pia Ines [Verfasser], Jürgen [Akademischer Betreuer] Geist, Jürgen [Gutachter] Geist, Wolfgang [Gutachter] Liebl et Andrew [Gutachter] Millard. « Impact of biotic and abiotic environmental variables on the toxic potential of the cyanobacterium Microcystis sp. / Pia Ines Scherer ; Gutachter : Jürgen Geist, Wolfgang Liebl, Andrew Millard ; Betreuer : Jürgen Geist ». München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/1162621214/34.

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Escalante, 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.

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Karim, 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.

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Matheson, Leah J. « Abiotic and biotic reductive dehalogenation of halogenated methanes / ». Full text open access at:, 1994. http://content.ohsu.edu/u?/etd,241.

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Jain, Ritu Shree. « Rice response to simultaneous biotic and abiotic stresses ». Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/6415/.

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With the predicted climate change and an ever-growing population there is increasing pressure to develop crop plants with improved stress responses, increased yield and high nutritive value. We have explored transcriptomic changes in the leaves and roots of rice plants (Oryza sativa japonica cv Nipponbare) in response to drought and the root-knot nematode Meloidogyne graminicola. A glasshouse model was developed to mimic conditions experienced by rice plants in the field. The plant responses under simultaneous biotic and abiotic stress were dominated by the drought element accompanied by a unique set of genes that were only responsive to the simultaneous stress. Highlighted within this group were novel members of stress-responsive gene families for example cytochrome P450, wall-associated kinases, lipid transfer proteinlike proteins and new candidate genes that may play important roles in the response of rice to multiple stresses. The genes that were differentially regulated between the multiple and the drought stress treatment were explored using loss-of-function mutants. The loss-of-function mutant for peroxidase precursor gene (per) showed improved growth and yield compared to the wildtype Nipponbare plants. The experiments conducted in growth rooms were validated in a field study. Both Nipponbare rice plants, and the popular lowland indica rice cv IR64 were grown under prolonged vegetative drought stress accompanied by cyst nematode or root-knot nematode infection. Reduction of phytate, an anti-nutrient, has been adopted as a major strategy to improve the nutritional value of crop plants. Nematode susceptibility of low phytate Arabidopsis plants was studied to determine the effect of reduced phytate content on the plant’s defence response. The study has provided insight into the genome-wide transcriptional changes in rice under a combined biotic and abiotic stress. It has led to better understanding of the stress responses in plants that will be advantageous in developing crop varieties with improved yield and nutritive value.
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VENULEO, MARIANNA. « Algal responses to abiotic and biotic environmental changes ». Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245503.

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L’eterogeneità delle risposte fisiologiche delle microalghe ai cambiamenti ambientali rappresenta uno dei fattori più importanti nel determinare le interazioni tra le specie in ambiente. La mia ricerca ha rivelato che specie differenti sono diversamente inclini a modificare la propria composizione cellulare in risposta ai cambiamenti ambientali. La scelta tra acclimatazione e omeostasi dipende anche dal tipo e dalla durata della perturbazione in esame. La maggior parte delle alghe considerate nel mio studio, per esempio, ha mostrato una risposta omeostatica ai cambiamenti nelle concentrazioni ambientali di CO2 e nella forma di azoto disponibile. Non è stato ritrovato nessun legame tra la strategia di risposta e la tassonomia delle alghe. Particolare attenzione è stata rivolta a Chromera velia, parente prossima dei parassiti Apicomplexa e probabile simbionte di coralli dell’ordine Scleractinia. C. velia si è dimostrata perfettamente in grado di vivere ad alta CO2. Questa condizione ha stimolato la produzione di C organico da parte di C. velia, incrementato la sua efficienza di utilizzo dei nutrienti e ha determinato cambiamenti nei rapporti stechiometrici tra gli elementi. Si può ipotizzare, dunque, che l’elevata concentrazione di CO2 rinvenuta all’interno dei tessuti del corallo che circondano il simbionte possa facilitare la vita di quest’alga in simbiosi. Infine, ho potuto dimostrare che le interazioni tra alghe e ambiente possono avere conseguenze nei rapporti tra alghe e loro predatori. I miei esperimenti hanno mostrato che i copepodi (ma non i rotiferi) possono discriminare tra alghe che sono identiche in ogni aspetto tranne che nella composizione cellulare. La storia nutrizionale delle alghe, dunque, essendo uno dei principali determinanti della loro composizione cellulare, risulta un elemento di grande importanza nelle relazioni tra alghe e predatori.
Algae 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.
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Madeo, M. « MEDICINAL PLANT RESPONSE TO ABIOTIC AND BIOTIC STRESS ». Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150114.

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Medicinal plants have always been considered a rich source of secondary metabolites that promote human health. Quality and property of medicinal plants strictly depend on secondary metabolites profile. They also play important roles in plant physiological processes and in ecological systems. The environment exerts a selective pressure on plants and these molecules actively participate to the plant response and adaptation. Amongst secondary metabolite, the phenolic compounds possess properties able to prevent oxidative stress. Therefore, an enhancement of the amount of phenolic compounds can be observed under different environmental factors. With this project we aimed to study the phenolic compounds of the medicinal plant Achillea collina Becker ex Rchb. cv “SPAK”, and their implication in physiological and biochemical response to abiotic and biotic stresses. We seek the possibility to increase the synthesis of phenolics with health properties or useful as potential control agents of insect pests. Abiotic stress. Hydroponic culture was used to evaluate the effect of long-term mineral, nitrogen starvation (abiotic stress) in A. collina. By means of HPLC-DAD-ESI/MS and NMR techniques, the content and the qualitative profile of A. collina methanol soluble phenolics, were evaluated. We concluded that the methanol extracts of A. collina leaves and roots are rich in hydroxycinnamic acids such as chlorogenic acid (2.33 ± 0.3 mg g-1 Dw), 3,5-di-O-caffeoylquinic acid (10.7 ± 4.2 mg g-1 Dw) and 4,5-di-O-caffeoylquinic acid (0.88 ± 0.24 mg g-1 Dw). The content of hydroxycinnamic acids significantly increased in plants growth under mineral nitrogen starvation, respect to the control plants. Chlorogenic acid increased by 2.5 and 3-fold and 3,5-di-O-caffeoylquinic acid increased by 8.5 and 35-fold in leaves and root, respectively. Biotic stress. A. collina plants cultivated in soil were infested with the phloem feeders aphids. We set up the system (e.g., age of plant, type of the cage, number of insects per plant, duration of infestation) to co-cultivated the plants with specialist (Macrosiphoniella millefolii) and generalist (Myzus persicae Sulzer) aphids. Plant growth, water and total protein content were evaluated. Based on a preliminary assessment of phenolic fingerprint, further extractions and separations were performed on A. collina leaves, to obtained soluble and cell wall-bound fractions and their sub-classes. Our results showed that A. collina plants were strongly affected by aphid infestation. Twenty days after infestation, the fresh weight was twenty-fold and seven-fold increased, in control and infested plants. Water and protein content, condensed tannins and methanol soluble phenolics content, were not affected by the aphid infestation. Cell wall-bound phenolics content increased in infested plants. The main phenolics were found to be chlorogenic acid and 3,5-di-O-caffeoylquinic in methanol soluble fraction, and caffeic acid in cell wall fraction. The chromatographic profiles showed that the main hydroxycinnamic acids were present in control and in both M. persicae and M. millefolli infested plants. The quantitative analysis indicated that the levels of chlorogenic acid and 3,5-di-O-caffeoylquinic acid, were 44% and 37% higher in M. persicae infested plants, respectively. The levels of chlorogenic acid and 3,5-di-O-caffeoylquinic acid, were 27% and 39% higher in M. millefolli infested plants, respectively. Twenty days after infestation the content of caffeic acid was resulted 43% and 34% higher in M. persicae and M. millefolli infested plants, respectively. These differences should indicate the different evolutionary interaction between plant and generalist/specialist aphid. We hypotheses that the increase of these molecules may represent a plant resistance mechanism against aphid attack. Finally, a chemometric approach, by means multivariate statistical analysis, was applied on chromatogram profiles to verify whether there is difference between methanol soluble fraction of infested and non infested A. collina plants. The discriminant analysis showed a significant effect of phloem feeders aphids on soluble phenolic compounds and indicated two peaks, not yet identified, that separate control from infested plants. In conclusion the model system developed to cultivate A. collina was useful to understand the metabolic basis of the environment interactions. The main hydroxycinnamic acids identified, were resulted increased in both abiotic and biotic stress, suggesting their implication in A. collina protection to environmental controversies.
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Livres sur le sujet "Abiotic and biotic variables"

1

Brannon, James M. Abiotic and biotic TNT transformations. Vicksburg, Miss : U.S. Army Engineer Waterways Experiment Station, 1997.

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Sinha, Bhav Kumar, et Reena. Abiotic & ; Biotic Stress Management in Plants. London : CRC Press, 2022. http://dx.doi.org/10.1201/9781003281986.

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Sinha, Bhav Kumar, Reena et Surendra Prasad. Abiotic and Biotic Stress Management in Plants. London : CRC Press, 2022. http://dx.doi.org/10.1201/9781003286134.

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Vats, Sharad, dir. Biotic and Abiotic Stress Tolerance in Plants. Singapore : Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-9029-5.

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Tóth, Gábor. Geomorphological environments : Research methods on biotic and abiotic environments. Stuttgart : Gebrüder Borntraeger, 2012.

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Mohamed, Heba I., Hossam El-Din Saad El-Beltagi et Kamel A. Abd-Elsalam, dir. Plant Growth-Promoting Microbes for Sustainable Biotic and Abiotic Stress Management. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66587-6.

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Al-Khayri, Jameel M., Shri Mohan Jain et Dennis V. Johnson, dir. Advances in Plant Breeding Strategies : Agronomic, Abiotic and Biotic Stress Traits. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-22518-0.

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FRaser, Brian Gordon. Boundary flux of the hyporheic zone as determined by biotic and abiotic indicators. Ottawa : National Library of Canada, 1995.

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M, Huang P., dir. Soil abiotic and biotic interactions and impact on the ecosystem and human welfare. Enfield, (NH) : Science Publishers, 2004.

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Gribko, Linda S. Biotic and abiotic mechanisms in the establishment of northern red oak seedlings : A review. Newtown Square, PA : USDA Forest Service, Northeastern Research Station, 2002.

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Chapitres de livres sur le sujet "Abiotic and biotic variables"

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Tresco, Patrick A., et Greg A. Gerhardt. « The Biotic-Abiotic Interface ». Dans Brain-Computer Interfaces, 31–45. Dordrecht : Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-8705-9_3.

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De Angelis, Hernan Horacio. « Abiotic and Biotic Resources ». Dans Archaeology of the Hunter-Gatherers of the Central Mountains of Tierra del Fuego, 1–13. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-81022-1_1.

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Stambaugh, Tamra, Eric Fecht et Emily Mofield. « Biotic and Abiotic Cubes ». Dans Interactions in Ecology and Literature, 46–51. New York : Routledge, 2021. http://dx.doi.org/10.4324/9781003235828-11.

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Marchetti, Michael P., Theo Light, Joaquin Feliciano, Trip Armstrong, Zeb Hogan, Joshua Viers et Peter B. Moyle. « Homogenization of California’s Fish Fauna Through Abiotic Change ». Dans Biotic Homogenization, 259–78. Boston, MA : Springer US, 2001. http://dx.doi.org/10.1007/978-1-4615-1261-5_13.

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Robert-Seilaniantz, Alexandre, Rajendra Bari et Jonathan D. G. Jones. « A Biotic or Abiotic Stress ? » Dans Abiotic Stress Adaptation in Plants, 103–22. Dordrecht : Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-3112-9_6.

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Kuppusamy, Pandiyan, Samadhan Yuvraj Bagul, Sudipta Das et Hillol Chakdar. « Microbe-Mediated Abiotic Stress Alleviation : Molecular and Biochemical Basis ». Dans Plant Biotic Interactions, 263–81. Cham : Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-26657-8_16.

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Hill, J., H. C. Becker et P. M. A. Tigerstedt. « Breeding for biotic and abiotic stress ». Dans Quantitative and Ecological Aspects of Plant Breeding, 212–34. Dordrecht : Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5830-5_8.

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Garg, Neera, Kiran Saroy, Amandeep Cheema et Aditi Bisht. « Microbial Diversity in Soil : Biological Tools for Abiotic Stress Management in Plants ». Dans Plant Biotic Interactions, 283–321. Cham : Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-26657-8_17.

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Barón, M., J. Rahoutei, J. J. Lázaro et I. García-Luque. « PSII Response to Biotic and Abiotic Stress ». Dans Photosynthesis : from Light to Biosphere, 3861–64. Dordrecht : Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-009-0173-5_910.

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Verma, Sandhya, Shadab Nizam et Praveen K. Verma. « Biotic and Abiotic Stress Signaling in Plants ». Dans Stress Signaling in Plants : Genomics and Proteomics Perspective, Volume 1, 25–49. New York, NY : Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-6372-6_2.

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Actes de conférences sur le sujet "Abiotic and biotic variables"

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Choi, H. J., et C. D. Montemagno. « Hybrid biotic/abiotic nanofactory ». Dans Smart Structures and Materials, sous la direction de Daniele Inaudi, Wolfgang Ecke, Brian Culshaw, Kara J. Peters et Eric Udd. SPIE, 2006. http://dx.doi.org/10.1117/12.657741.

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Kolb, Vera M., et P. J. Liesch. « Abiotic, biotic, and in-between ». Dans Optical Engineering + Applications, sous la direction de Richard B. Hoover, Gilbert V. Levin, Alexei Y. Rozanov et Paul C. Davies. SPIE, 2008. http://dx.doi.org/10.1117/12.792668.

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Konesky, Gregory. « Apparent biotic micromorphologies of abiotic origin ». Dans Optical Engineering + Applications, sous la direction de Richard B. Hoover, Gilbert V. Levin, Alexei Y. Rozanov et Paul C. W. Davies. SPIE, 2007. http://dx.doi.org/10.1117/12.732240.

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Engel, Michael H., Vlad E. Andrus et Stephen A. Macko. « Amino acids in carbonaceous meteorites : biotic or abiotic ? » Dans Optical Science and Technology, SPIE's 48th Annual Meeting, sous la direction de Richard B. Hoover et Alexei Y. Rozanov. SPIE, 2004. http://dx.doi.org/10.1117/12.504222.

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Montemagno, Carlo. « Engineering and Fabricating a Hybrid Biotic/Abiotic Biological Computer ». Dans 2006 IEEE International Symposium on MicroNanoMechanical and Human Science. IEEE, 2006. http://dx.doi.org/10.1109/mhs.2006.320312.

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Cavazos, Amanda, et Jennifer Glass. « Potential Biotic-Abiotic Nitrous Oxide Production in Oceanic Oxyclines ». Dans Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.341.

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Klenner, Fabian, Frank Postberg, Jon Hillier, Nozair Khawaja, Marie Dannenmann, Morgan L. Cable et Bernd Abel. « Discriminating Abiotic and Biotic Chemistry on Active Ocean Worlds ». Dans Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.1334.

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Montemagno, C. D. « Engineering and Fabricating a Hybrid Biotic/Abiotic Biological Computer ». Dans 2006 Sixth IEEE Conference on Nanotechnology. IEEE, 2006. http://dx.doi.org/10.1109/nano.2006.247590.

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Parsaev, Evgeniy, Nadezhda Filippova, Tat'yana Kobernickaya et Viktor Ostrovskiy. « New variety of Karlybas volzhski melilot for fodder production in northern Kazakhstan ». Dans Multifunctional adaptive fodder production23 (71). ru : Federal Williams Research Center of Forage Production and Agroecology, 2020. http://dx.doi.org/10.33814/mak-2020-23-71-73-77.

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Nazzi, Francesco. « Impact of biotic and abiotic stressors on honey bee health (Apis mellifera) ». Dans 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.93415.

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Rapports d'organisations sur le sujet "Abiotic and biotic variables"

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Frost, J. W. Biotic and abiotic carbon to sulfur bond cleavage. Office of Scientific and Technical Information (OSTI), janvier 1991. http://dx.doi.org/10.2172/5474561.

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Frost, J. W. Biotic and abiotic carbon to sulfur bond cleavage. Office of Scientific and Technical Information (OSTI), janvier 1991. http://dx.doi.org/10.2172/5215659.

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Tsukruk, Vladimir V. Nanostructured Interfaces for Organized Mesoscopic Biotic-Abiotic Materials. Fort Belvoir, VA : Defense Technical Information Center, septembre 2011. http://dx.doi.org/10.21236/ada563947.

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El-Naggar, Mohamed Y. Biotic-Abiotic Nanoscale Interactions in Biological Fuel Cells. Fort Belvoir, VA : Defense Technical Information Center, mars 2014. http://dx.doi.org/10.21236/ada602346.

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Frost, J. W. Biotic and abiotic carbon to sulfur bond cleavage. Final report. Office of Scientific and Technical Information (OSTI), mai 1994. http://dx.doi.org/10.2172/10150691.

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Szecsody, James E., Jim P. McKinley, Andrew T. Breshears, Brooks J. Devary, Fiona Crocker, Herbert L. Fredrickson et Karen Thompson. Abiotic and Biotic Mechanisms Controlling In Situ Remediation of NDMA. Fort Belvoir, VA : Defense Technical Information Center, mai 2009. http://dx.doi.org/10.21236/ada606789.

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Dunphy, Darren Robert, C. Jeffrey Brinker, Carlee E. Ashley, Helen Kennicott Baca, DeAnna M. Lopez et Eric C. Carnes. Discovery, integration, and interrogation of biotic/abiotic materials and systems. Office of Scientific and Technical Information (OSTI), octobre 2009. http://dx.doi.org/10.2172/1028941.

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Roso, Kevin M. Mechanisms and Dynamics of Abiotic and Biotic Interactions at Environmental Interfaces. Office of Scientific and Technical Information (OSTI), juin 2006. http://dx.doi.org/10.2172/895931.

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Gribko, Linda S., Thomas M. Schuler et W. Mark Ford. Biotic and abiotic mechanisms in the establishment of northern red oak seedlings : a review. Newtown Square, PA : U.S. Department of Agriculture, Forest Service, Northeastern Research Station, 2002. http://dx.doi.org/10.2737/ne-gtr-295.

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Szecsody, James E., James P. McKinley, Fiona H. Crocker, Andrew T. Breshears, Brooks J. Devary, Herbert L. Fredrickson et Karen T. Thompson. SERDP ER-1421 Abiotic and Biotic Mechanisms Controlling In Situ Remediation of NDMA : Final Report. Office of Scientific and Technical Information (OSTI), septembre 2009. http://dx.doi.org/10.2172/985590.

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