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Tanja, Tunić. "Razvoj testova inhibicije rasta vrsta roda Myriophyllum L. 1754 (Saxifragales, Haloragaceae) za potrebe ekološke procene rizika od herbicida i kontrole kvaliteta sedimenta." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2015. https://www.cris.uns.ac.rs/record.jsf?recordId=95450&source=NDLTD&language=en.
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Razvojem testova inhibicije rasta na vrstama roda Myriophyllum ispitan jepotencijal vrsta Myriophyllum aquaticum (Vell.) Verd. i Myriophyllum spicatum L. uekološkoj proceni rizika od herbicida i kontrole kvaliteta sedimenta. Ispitana jeprimenljivost kontaktnog testa toksičnosti sedimenta sa vrstom M. aquaticum uretrospektivnoj proceni rizika sedimenta na uzorcima iz prirode – na sedimentu reka Tamiš, Krivaja i Jegrička. Testom toksičnosti sedimenta obogaćenog atrazinom,analiziran je i potencijal kontaktnog testa u preventivnoj proceni rizika od hemikalijakoje pokazuju afinitet vezivanja za sediment. Testovima inhibicije rasta M. aquaticumi M. spicatum u voda-sediment sistemu ispitana je osetljivost i mogućnost primenemetode u preventivnoj proceni rizika od herbicida i regulatora rasta. Deo rezultata dobijenih u radu uključen je u završne izveštaje internacionalnihtestova interkalibracije metoda, a kao rezultat ovih aktivnosti usvojene su novestandardne metode na ukorenjenim akvatičnim makrofitama ISO 16191/2013 i OECD 239/2014. Na osnovu istraživanja, zaključeno je da je kontaktni test toksičnostisedimenta jednostavan i lak za izvođenje, kao i da je vrsta M. aquaticum u jedno-komponentnom sistemu (sediment) adekvatan test model. Rastom kontrolnih biljaka, niskom varijabilnošću i visokom osetljivošću bioloških odgovora zadovoljen je kriterijum validnosti testa. Preporučeno je korišćenje dodatne kontrole u slučajevima kada postoje značajna odstupanja u strukturi između standardnog sintetičkog kontrolnog i testiranog prirodnog sedimenta. Kontaktnim testom toksičnosti sedimenta obogaćenog atrazinom pokazano je da se ovaj test može smatrati potencijalno dobrom metodom za proširenje ekološke procene rizika od hemikalija koje pokazuju afinitet vezivanja za sediment. Ispitivanjem potencijala testa inhibicije rasta vrsta roda Myriophyllum u voda-sediment sistemu utvrđeno je da su testovi izvodljivi u praksi, da pokazuju visoki stepen stabilnosti, statističku snagu i malu varijabilnost većine ispitivanih parametara rasta. Poređenjem testova sa vrstama M. aquaticum i M. spicatum, nije utvrđena značajna razlika u osetljivosti na odabrane herbicide. Osetljivost testova na vrstama roda Myriophyllum i standardnih Lemna testova je bila slična, osim u slučaju auksin simulatora gde su vrste roda Myriophyllum sp. bile osetljivije, što ukazuje na njihovu primenljivost u proceni rizika od pesticida specifičnog mehanizma toksičnog dejstva. Iako obe vrste roda Myriophyllum imaju prednosti i nedostatke kao testorganizmi, vrste se mogu smatrati reprezentativnim akvatičnim ukorenjenimmakrofitama i predstavljati adekvatne dopunske test vrste u višim nivoima ekološkeprocene rizika od herbicida i regulatora rasta. Takođe, vrsta M. aquaticum je pogodna za testiranje u različitim test sistemima, a samim tim ima i veći potencijal primene u preventivnoj, ali i retrospektivnoj ekološkoj proceni rizika.Growth inhibition tests on Myriophyllum aquaticum (Vell.) Verd. and Myriophyllum spicatum L. were conducted in order to assess their use in refined risk assessment of chemicals, as well as in sediment risk assessment. The applicability, stability and sensitivity of the M. aquaticum sediment contact test on natural sediments (from rivers Tamiš, Krivaja and Jegrička) was assessed for use in retrospective ecological risk assessment (ERA). The potential use of the spiked sediment contact test in risk assessment of sediment bound chemicals was also investigated. The sensitivity and applicability of the growth inhibition tests on M. aquaticum and Myriophyllum spicatum in a water-sediment system was assessed for potential use in prospective ERA of plant protection products.A part of the results of this study was included in the final report of the two international ring tests, which resulted with new standardised methods with rooted macrophytes: ISO 16191/2013 i OECD 239/2014. Tests on Myriophyllum species were compared to standard Lemna tests. Test substances in M. aquaticum and Lemna minor L. tests were 3,5 dichlorphenol, atrazine, isoproturon, trifluralin, 2,4 D and dicamba, while substances used in M. spicatum tests were atrazine, isoproturon and 2,4 D.The sediment contact test proved to be simple and robust, while M. aquaticum can be considered as an adequate test model in a one-compartment (sediment) test. The validity criteria regarding control plant growth and variability was met. The use of an additional control is suggested when testing of sediments with considerably different properties of the standard synthetic control is taking place. The spiked sediment contact tests with atrazine showed that the method could be applied in prospective risk assessment of sediment bound chemicals.The water-sediment growth inhibition test with Myriophyllum species proved to be applicable in practice, with high stability, statistical power and low variability of the majority of the growth parameters. M. aquaticum and M. spicatum didn’t show major differences in sensitivity to tested substance. The sensitivity of Myriophyllum and Lemna tests was also similar, except to auxin simulators, where Myriophyllum species were considerably more sensitive, which makes them adequate candidates for use in risk assessment of chemicals with specific mode of action.Even though both Myriophyllum species show advantages and disadvantages as test organisms, they can be regarded as representative rooted aquatic macrophyte species and additional test species in refined risk assessment of herbicides and growth regulators. Also, M. aquaticum can be tested in various test syytems, which makes this species applicable in prospective as well as retrospective ecological risk assessment.
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Caillat, Amélie. "Evaluation de la biodisponibilité du cuivre dans des sédiments artificiels par des méthodes biologiques avec la plante aquatique Myriophyllum aquaticum (hydroponie, biotest normalisé et Rhizotest) et géochimiques (DGT)." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4310.
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Les travaux menés durant cette thèse ont visé à évaluer la pertinence de la plante aquatique Myriophyllum aquaticum pour l'étude de la biodisponibilité du cuivre dans des sédiments ainsi que l'intérêt de la technique du gradient de diffusion en couche mince (DGT) comme outil biomimétique de cette plante. Une première expérimentation réalisée avec la plante M.aquaticum exposée selon le protocole du biotest normalisé (sous forme de verticilles) dans des sédiments artificiels dopés en cuivre a montré que ce biotest semble être un outil intéressant pour l'évaluation de la toxicité de sédiments contaminés en cuivre. En outre, aucune corrélation n'a été observée entre les mesures DGT et la bioaccumulation dans la plante M.aquaticum. Ceci est probablement lié aux conditions d'exposition des plantes. En effet, le développement des racines se faisant au cours de l'expérimentation, les processus d'incorporation du métal dans la plante ne sont donc pas constants au cours de l'expérience. Suite à ces résultats nous avons réalisé deux autres séries d'expérimentations (hydroponie et Rhizotest) dans lesquelles, les plantes ont été exposées selon un protocole modifié (plantes ayant déjà développé des racines avant leur exposition dans le sédiment). Ces expérimentations nous ont permis de montrer que la plante M.aquaticum est plutôt sensible au cuivre et qu'elle a une forte capacité à l'accumuler. De plus, les résultats obtenus ont permis de montrer que la technique DGT semble être un bon outil biomimétique de cette plante dans le cas où elle est exposée avec des racines car le prélèvement par la plante est limité par la capacité de la phase solide à réapprovisionner le métal en solutionThe work carried out during this thesis aimed to assess the relevance of the aquatic plant Myriophyllum aquaticum to study the bioavailability of copper in sediments as well as the interest of the technique of diffusion gradient in thin film (DGT) as a biomimetic tool of this plant. A first experiment, performed with the plant M.aquaticum exposed according to the protocol of the standardized bioassay (as whorls) in an artificial sediment spiked with copper, showed that this bioassay appears to be a useful tool for assessing the toxicity of contaminated sediments copper. Furthermore, no correlation was observed between DGT measurements and bioaccumulation in the M.aquaticum plant. This is probably due to the exposure conditions of the plants. In fact, as the root development occurs during the experiment, the process of incorporating the metal into the plant is therefore not constant throughout the experiment.Following these results we conducted two other series of experiments (hydropony and Rhizotest) in which, plants were exposed following a modified protocol (plants having already developed roots before their exposure in the sediment). These experiments showed that the plant M.aquaticum is rather sensitive to copper and has a strong ability to accumulate it. Futhermore, the results have shown that the DGT technique seems to be a good biomimetic tool for this plant when it is exposed by roots because the plant uptake is limited by the capacity of the solid phase to replenish the metal in solution
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Smith, Dian H. (Dian Helen). "Nutrient Effects on Autofragmentation of Myriophyllum Spicatum L." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc279354/.
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A 2 x 2 factorial design investigated effects of sediment nitrogen and water potassium levels on autofragment production. Reduced nitrogen levels significantly increased autofragment production whereas potassium levels did not significantly alter production. Up to 50% of autofragment production abscised from parent plants grown under low nitrogen conditions compared to 12% or less under high nitrogen conditions.
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Baydoun, Mohamad. "Intérêt du macrophyte Myriophyllum alterniflorum pour la détection de contaminants dans l'environnement." Thesis, Limoges, 2018. http://www.theses.fr/2018LIMO0087.
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Le but de ce travail de thèse est de démontrer l’intérêt d’un macrophyte aquatique submergé, Myriophyllum alterniflorum pour la détection de contaminants dans l’environnement. Des études in situ ont été réalisées pendant 28 jours sur cinq milieux aquatiques, affectés par différents types de pression anthropique, durant trois campagnes de terrain (printemps 2015, automne 2015 et printemps 2016), pour déterminer si l’accumulation des contaminants dans la plante et si des biomarqueurs du myriophylle peuvent être utilisés pour détecter la présence de contaminants dans les eaux. L’accumulation des contaminants au cours du temps était corrélée avec les teneurs des contaminants dans l’eau ; l’influence de la durée d’exposition a été étudiée. Au cours des trois campagnes, la réponse des biomarqueurs, teneur en MDA et activité de nitrate réductase était corrélée avec les teneurs en contaminants dans l’eau et dans la plante ; cependant l’influence de la durée d’exposition sur l’évolution de la réponse des biomarqueurs est moindre par rapport à celle de l’accumulation des contaminants. Ainsi, l’étude des biomarqueurs pourrait permettre une évaluation plus fiable de la qualité des masses d’eau que le suivi de l’accumulation dans la plante. Au cours de la campagne printemps 2015, un panel de biomarqueurs plus large a été étudié afin de définir les biomarqueurs les plus pertinents pour détecter spécifiquement les pressions liées aux activités urbaines ou industrielles. Une méthodologie d’évaluation de la qualité des eaux est proposée, en considérant un protocole d’analyse des biomarqueurs : un premier dosage de Chlb et MDA est simple et moins coûteux. Quand aucune preuve d'impact anthropique n'est montrée, aucune analyse complémentaire n'est requise. En revanche, lorsqu’une altération est mise en évidence, l’analyse d'autres biomarqueurs plus spécifiques tels que les activités G6PDH et γ-GCS sera nécessaire. La réponse de l'activité γ-GCS est spécifique du stress métallique, ainsi, la réponse de ce biomarqueur devrait amener à réaliser l’analyse des métaux/métalloïdes dans M. alterniflorumThe aim of this thesis is to demonstrate the interest of a submerged aquatic macrophyte, Myriophyllum alterniflorum for the detection of contaminants in the environment. In situ studies were conducted over 28 days in five aquatic environments, affected by different levels of anthropogenic pressure, during three field seasons (spring 2015, autumn 2015 and spring 2016), to determine whether the accumulation of contaminants in the plant and whether biomarkers can be used to detect the presence of contaminants in water. The accumulation of contaminants over time was correlated with the levels of contaminants in the water; the influence of the duration of exposure has been studied. In all three campaigns, biomarker response, MDA content, and nitrate reductase activity were correlated with contaminant levels in water and in the plant; however, the influence of the duration of exposure on the evolution of the biomarker response is lower compared to the accumulation of contaminants. Thus, the study of biomarkers could allow a more reliable assessment of the quality of water bodies than the monitoring of contaminant accumulation in the plant. During the spring 2015 campaign, a much broader biomarker panel was investigated to define the most relevant biomarkers for assessing water quality. A methodology for evaluating water quality is proposed, considering a biomarker analysis protocol: a first assay of Chlb and MDA is simple and less expensive. When no evidence of human impact is shown, no further analysis is required. On the other hand, when an alteration is highlighted, the analysis of other more specific biomarkers such as G6PDH and γ-GCS activities will be necessary. The response of γ-GCS activity is specific for metal stress, so the response of this biomarker should lead to the analysis of metals / metalloids in M. alterniflorum
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Metzger, Genevieve. "CLONALITY AND GENETIC DIVERSITY IN POLYGONELLA MYRIOPHYLLA, A LAKE WALES RIDGE ENDEMIC PLANT." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2103.
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Although capable of sexual reproduction, many plants also rely heavily on clonal reproduction. The formation of multiple, physiologically-independent units with the same genotype has important implications for spatial genetic structure and genetic diversity in these plants. The endangered scrub-dwelling perennial, Polygonella myriophylla is known to reproduce both sexually and clonally but no study to date has been able to investigate the spatial genetic patterns that occur in this species. I use microsatellite markers to investigate questions about clonal structure and genetic diversity in five populations of P. myriophylla and address some of the implications of my findings for conservation of this species: Overall, I find that 57% of sampled clusters of P. myriophylla are composed of a single genet (genetic individual) with multiple physiological units (ramets) while the remainder are made up of two or more genets. I found differences in both clonal reproduction and genetic diversity among populations. I also found evidence of limited gene flow even over small spatial scales (less than 10 km) and for at least 4 genetic clusters occurring within the species range. Despite high levels of genetic diversity overall, there is evidence of reduced genetic diversity in two populations My results suggest that high levels of clonality may be important in maintaining genetic diversity in P. myriophylla. I also provide evidence that dirt roadsides may not represent a refuge for this species.M.S.
Department of Biology
Sciences
Biology MS
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Bailey, Jacolyn E. "Myriophyllum heterophyllum Michx. (Haloragaceae) : control and vegetative reproduction in southwestern Maine /." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/BaileyJE2007.pdf.
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Comstock, Kelly K. "Transformation of 2,4,6-trinitrotoluene (TNT) by the aquatic plant myriophyllum spicatum." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/21272.
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Richter, Doreen [Verfasser]. "Interaktionen zwischen Charophyceen und dem Ährigen Tausendblatt (Myriophyllum spicatum) / Doreen Richter." Konstanz : Bibliothek der Universität Konstanz, 2015. http://d-nb.info/1080908846/34.
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Snow, Joe R. "Establishment and Competitive Ability of Nelumbo Lutea in Relation to Myriophyllum Spicatum." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2694/.
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Limitations from reduced light and increasing water depth on Nelumbo lutea seedlings were determined in tank experiments. Survival was high in all tested light levels. Total biomass increased significantly with increasing light. Biomass allocation shifted significantly to root production between 3 and 6 weeks in the 10 and 24% levels. Survival decreased with increasing planting depth, and biomass of survivors reduced significantly between 0.5, 1.0, and 1.5 m depths. Nelumbo lutea and Myriophyllum spicatum populations were monitored for one season in a 0.7 ha pond to track changes in species dominance. Myriophyllum spicatum dominated early, and N. lutea dominated from July through October, suppressing M. spicatum at all depths. Competitive interactions between N. lutea and M. spicatum were investigated for two seasons in a container experiment situated within a pond. Where established, N. lutea dominated in the presence of M. spicatum. However, N. lutea could not be established in depths greater than 1 meter.
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Balci, Pinar. "Ecology of Chironomids Associated with Myriophyllum Spicatum L. and Heteranthera Dubia Macm." Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc5803/.
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Macroinvertebrate communities inhabiting an exotic, Myriophyllum spicatum, and a native, Heteranthera dubia macrophyte were studied from March 1999 to June 2000 in experimental ponds. Although macrophyte architecture explained some variation in macroinvertebrate abundance between the two macrophytes, most variation was explained by the sampling months. Total number of macroinvertebrates was found to be positively correlated with epiphyton biomass which differed significantly between the two plant types and among sampling months. Taxa richness did not vary between the two plant types. Chironomid larvae were the most abundant organisms and dominated by Apedilum elachistus on both plant communities. Annual production of five chironomid species was estimated by the size-frequency method. Production estimates (P) in g dry wt m-2 yr-1 of plant surface area for the predator Tanypodinae larvae were: Larsia decolarata, P= 0.77 and 0.67, Labrundinia virescens, P= 0.59 and 0.35 on M. spicatum and H. dubia, respectively. Larvae of Cricotopus sylvestris and Psectrocladius vernalis were collected from M. spicatum from March to mid-June. Production of C. sylvestris was found to be 0.46 g dry wt m-2, whereas it was 0.07 g dry wt m-2 for P. vernalis for this period. Apedilum elachistus exhibited the highest productivity: 9.9 g dry wt m-2 yr-1 of plant surface area on M. spicatum, and 8.5 g dry wt m-2 yr-1 on H. dubia. These production estimates are among the highest production values reported for a single species. Additionally, post-ovipositing development times for five chironomid species collected from Myriophyllum and Heteranthera were determined. Three different temperatures (15°, 20° and 25°C) were chosen to rear eggs under 12L: 12D photoperiod. Egg development times ranged between 1-4 days. Larval development times ranged from 44 days at 20°C for Tanypus neopunctipennis to as few as 9 days at 20°C for Larsia decolorata.
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Horn, Kristina Dianne. "DOES HABITAT AFFECT CLONAL DEMOGRAPHY? AN EXPERIMENT WITH POLYGONELLA MYRIOPHYLLA IN ROADSIDE AND FLORIDA SCRUB." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2916.
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Polygonella myriophylla (Polygonaceae) is a clonal shrub listed as endangered and narrowly endemic to pyrogenic scrub ecosystems in central Florida. It is almost restricted to gaps within the matrix of shrubs in the scrub but also occurs along adjacent road-side habitats. I hypothesize that persistent disturbed microhabitats and more dynamic sand accretion in roadsides will increase rooting probabilities compared to more stable scrub habitats, affecting survival, growth and reproduction. In April 2004- March 2006, I compared plant (genet) and basal branch (ramet) performance between experimentally manipulated plants in native scrub and roadside habitats at two locations within the Lake Wales Ridge State Forest in Polk County: LC01 and Old School. We completed a total of 6 evaluations in each site (April, July and November 2004, May and November 2005, and March 2006). Fifteen plants per replicated habitat in LCO1 and Old School were selected based on presence of four unrooted branches. Each unrooted branch within a plant randomly received one of four possible treatments: forced branch burial, branch lifting, procedural control, and no manipulation (total N= 60 genets and 240 ramets). Forced burial was implemented to mimic sand burial and evaluate rooting probability and performance in both habitats. Branch lifting was applied to prevent sand burial and evaluate demography of unrooted branches in both habitats. The procedural control served to evaluate wire effects on ramet demography. The control provided vital and rooting rates of branches in natural conditions. Road populations exhibited larger crown area and higher monthly diameter (controlled by initial diameter) and higher monthly length growth rates compared to scrub populations. Rooting probability was only affected by treatment one (buried wire) not habitat or site. Forced sand burial increased rooting (67 % after forced contact vs. 20-30 % for other treatments). Rooted branches did not exhibit variation in survival, growth, or fecundity compared to unrooted branches. Old School populations exhibited larger crown area, higher monthly diameter and monthly length growth rates compared to LC01 populations. Prescribed fires killed several plants explaining significantly higher branch survival at the unburned LC01 (66.1%) compared to recently burned Old School (36.2 %). LC01 populations exhibited higher fecundity and ramet survival compared to Old School populations. In February – December 2006, I describe the reproductive schedule at (LC01) in 10 road and 10 scrub plants. Monthly, I counted number of inflorescences and flowers per inflorescence (one inflorescence per plant) for each plant. Number of inflorescences per plant was highest between May and September and higher in road than in scrub. Our results indicate significant different demographic performance of P. myriophylla at plant and branch level between road and scrub habitats. A longer term study is needed to determine if the persistence of P. myriophylla is threatened by increasing roadside populations.M.S.
Department of Biology
Sciences
Biology MS
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Condorhuamán, Figueroa Yovani Martín. "Efecto hipotensor del extracto acuoso de Calceolaria myriophylla kraenz en ratas hipertensas inducidas por L-NAME." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2009. https://hdl.handle.net/20.500.12672/238.
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El objetivo de este estudio experimental ha sido evaluar el posible efecto hipotensor, diurético y tóxico del extracto acuoso de Calceolaria myriophylla Kraenz (zapatilla). Material y Métodos: se utilizó ratas albinas machos de raza Holtzmann para la determinación de los efectos, a quienes después de una semana de adaptación se les midió la presión arterial basal sistólica, diastólica y media. Para la determinación del efecto hipotensor se realizó la inducción con la administración de N-Nitro-L-Arginina Metíl Ester (L-NAME) a dosis de 40 mg/kg/día por vía oral durante 05 días y nuevamente se les midió la presión arterial postinducción, se dividió en 06 grupos de 08 animales; grupo control positivo (L-NAME) y control negativo (agua destilada), grupos experimentales a dosis de 50 mg/kg, 100 mg/kg, 200 mg/kg y enalapril a dosis de 25 mg/kg. El tratamiento fue durante 30 días midiéndose la presión arterial cada 5 días. El efecto diurético se evaluó utilizando ratas normotensas distribuidas en 05 grupos de 09 animales; grupo control (agua destilada), grupos a dosis de 50 mg/kg, 100 mg/kg, 200 mg/kg y furosemida a dosis de 10 mg/kg. La evaluación de la actividad antioxidante se realizó a los grupos determinados en el efecto hipotensor. El estudio del efecto tóxico se determino en el ensayo a dosis repetidas por 60 días a nivel hematológico, bioquímico y anatomopatológico en ratas normotensas distribuidas en 03 grupos de 06 animales; utilizando dosis de 100 mg/kg, 200 mg/kg y un grupo control (agua destilada). Resultados: El extracto acuoso de Calceolaria myriophylla Kraenz presentó efecto hipotensor y diurético a las dosis indicadas por vía oral. El extracto acuoso elevó los niveles séricos de óxido nítrico y disminuyo los niveles séricos de malondialdehido. No presentó efecto tóxico en el ensayo a dosis repetidas por 60 días. Conclusiones: Se demostró que el extracto acuoso de Calceolaria myriophylla Kraenz presenta efecto hipotensor, diurético y antioxidante sin efectos tóxicos.The objective of this experimental study has been to evaluate the possible hypotensive, diuretic and toxic effect of aqueous extract of Calceolaria myriophylla Kraenz (zapatilla). Material and Methods: used albino rats male Holtzmann race for the determination of the effects, after one week of adaptation was measured basal systolic, diastolic and mean pressure. For the determination of the hypotensive effect the induction was realised with the administration of N-nitro-L-Arginine Methyl Ester (L-NAME) to doses of 40 mg/kg/día by oral route during 05 days and again the arterial pressure was measured postinduction, was divided in 06 groups of 08 animal; group positive control (L-NAME) and negative control (distilled water), experimental groups to 50 doses of mg/kg, 100 mg/kg, 200 mg/kg and enalapril to 25 doses of mg/kg. The treatment was during 30 days being measured the arterial pressure every 5 days. The diuretic effect was evaluated using rats normotensas distributed in 05 groups of 09 animals; group control (distilled water), groups to 50 doses of mg/kg, 100 mg/kg, 200 mg/kg and furosemida to 10 doses of mg/kg. The evaluation of the antioxidant activity was realised to the groups determined in the hypotensor effect. The study of the toxic effect was determined in the test to doses repeated by 60 days at hematological, biochemical and anatomopatológico level in normotensas rats distributed in 03 groups of 06 animal; using 100 doses of mg/kg, 200 mg/kg and a group control (distilled water). Results: The aqueous extract of Calceolaria myriophylla Kraenz induced hypotensive and diuretic effects to the doses indicated by oral route. The aqueous extract increased the serum levels nitric oxide and decreased serum levels of malondialdehido. No toxic effect in the test to doses repeated by 60 days. Conclusions: These results suggest that oral administration of aqueous extract of Calceolaria myriophylla Kraenz exhibited hypotensive, diuretic, antioxidant actions without toxic effects.
Tesis
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Condorhuamán, Figueroa Yovani Martín, and Figueroa Yovani Martín Condorhuamán. "Efecto hipotensor del extracto acuoso de Calceolaria myriophylla kraenz en ratas hipertensas inducidas por L-NAME." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2009. http://cybertesis.unmsm.edu.pe/handle/cybertesis/238.
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El objetivo de este estudio experimental ha sido evaluar el posible efecto hipotensor, diurético y tóxico del extracto acuoso de Calceolaria myriophylla Kraenz (zapatilla). Material y Métodos: se utilizó ratas albinas machos de raza Holtzmann para la determinación de los efectos, a quienes después de una semana de adaptación se les midió la presión arterial basal sistólica, diastólica y media. Para la determinación del efecto hipotensor se realizó la inducción con la administración de N-Nitro-L-Arginina Metíl Ester (L-NAME) a dosis de 40 mg/kg/día por vía oral durante 05 días y nuevamente se les midió la presión arterial postinducción, se dividió en 06 grupos de 08 animales; grupo control positivo (L-NAME) y control negativo (agua destilada), grupos experimentales a dosis de 50 mg/kg, 100 mg/kg, 200 mg/kg y enalapril a dosis de 25 mg/kg. El tratamiento fue durante 30 días midiéndose la presión arterial cada 5 días. El efecto diurético se evaluó utilizando ratas normotensas distribuidas en 05 grupos de 09 animales; grupo control (agua destilada), grupos a dosis de 50 mg/kg, 100 mg/kg, 200 mg/kg y furosemida a dosis de 10 mg/kg. La evaluación de la actividad antioxidante se realizó a los grupos determinados en el efecto hipotensor. El estudio del efecto tóxico se determino en el ensayo a dosis repetidas por 60 días a nivel hematológico, bioquímico y anatomopatológico en ratas normotensas distribuidas en 03 grupos de 06 animales; utilizando dosis de 100 mg/kg, 200 mg/kg y un grupo control (agua destilada). Resultados: El extracto acuoso de Calceolaria myriophylla Kraenz presentó efecto hipotensor y diurético a las dosis indicadas por vía oral. El extracto acuoso elevó los niveles séricos de óxido nítrico y disminuyo los niveles séricos de malondialdehido. No presentó efecto tóxico en el ensayo a dosis repetidas por 60 días. Conclusiones: Se demostró que el extracto acuoso de Calceolaria myriophylla Kraenz presenta efecto hipotensor, diurético y antioxidante sin efectos tóxicos.The objective of this experimental study has been to evaluate the possible hypotensive, diuretic and toxic effect of aqueous extract of Calceolaria myriophylla Kraenz (zapatilla). Material and Methods: used albino rats male Holtzmann race for the determination of the effects, after one week of adaptation was measured basal systolic, diastolic and mean pressure. For the determination of the hypotensive effect the induction was realised with the administration of N-nitro-L-Arginine Methyl Ester (L-NAME) to doses of 40 mg/kg/día by oral route during 05 days and again the arterial pressure was measured postinduction, was divided in 06 groups of 08 animal; group positive control (L-NAME) and negative control (distilled water), experimental groups to 50 doses of mg/kg, 100 mg/kg, 200 mg/kg and enalapril to 25 doses of mg/kg. The treatment was during 30 days being measured the arterial pressure every 5 days. The diuretic effect was evaluated using rats normotensas distributed in 05 groups of 09 animals; group control (distilled water), groups to 50 doses of mg/kg, 100 mg/kg, 200 mg/kg and furosemida to 10 doses of mg/kg. The evaluation of the antioxidant activity was realised to the groups determined in the hypotensor effect. The study of the toxic effect was determined in the test to doses repeated by 60 days at hematological, biochemical and anatomopatológico level in normotensas rats distributed in 03 groups of 06 animal; using 100 doses of mg/kg, 200 mg/kg and a group control (distilled water). Results: The aqueous extract of Calceolaria myriophylla Kraenz induced hypotensive and diuretic effects to the doses indicated by oral route. The aqueous extract increased the serum levels nitric oxide and decreased serum levels of malondialdehido. No toxic effect in the test to doses repeated by 60 days. Conclusions: These results suggest that oral administration of aqueous extract of Calceolaria myriophylla Kraenz exhibited hypotensive, diuretic, antioxidant actions without toxic effects.
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Webb, Krisan Marie. "EVALUATION OF BLUEGILL (LEPOMIS MACROCHIRUS) FEEDING HABITS AFTER ERADICATION OF EURASIAN WATERMILFOIL (MYRIOPHYLLUM SPICATUM)." MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06152009-121102/.
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The objectives of this study were to determine effects of Eurasian watermilfoil (Myriophyllum spicatum) removal on bluegill feeding habits relative to diet composition, size, and feeding selectivity. Data were collected from 2003 through 2007 in four Minnesota lakes during June and September using boat electrofishing. Two lakes received an herbicide application of Endothall 2, 4-D, whereas remaining lakes were untreated and used as a reference. Bluegill diet composition, diets relative to size, and feeding selectivity were unaffected by vegetation removal, but varied seasonally with macroinvertebrate availability. Therefore, removal of Eurasian watermilfoil had minimal effects on bluegill feeding habits.
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Gräfe, Simon. "Relationship Between the Invasive Eurasian Milfoil (Myriophyllum spicatum L.) and Macrophyte Diversity Across Spatial Scales." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30331.
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The effect of the invasive macrophyte Myriophyllum spicatum L. on native macrophyte diversity was studied across 21 lakes at small (1 quadrat) and large (18 quadrats) scales and in mesocosms. No relationship was observed between M. spicatum and native richness at either spatial scale, or native evenness at small scales; however, at large scales native evenness was negatively correlated with the cover of M. spicatum in lakes. This suggests that M. spicatum can grow in lakes with other dominant species, contrary to predictions that invasive species will outcompete other dominant species. While macrophyte communities were mainly distinguished by environmental and spatial variables, M. spicatum was a significant predictor of the remaining variation in community composition. Within lakes M. spicatum occurred in deep water apart from other species; however, competition studies in mesocosms did not find sufficient evidence that this isolation was due to superior competitiveness.
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Rocchio, Patricia Mary. "Physiological Responses of Myriophyllum spicatum to Time Varying Exposures of Diquat, 2,4-D and Copper." Thesis, North Texas State University, 1988. https://digital.library.unt.edu/ark:/67531/metadc331163/.
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The physiological responses of Myriophyllum spicatum to 2,4-D, diquat and copper were quantified using a plant tissue viability assay, and daily measures of dissolved oxygen and pH. Correlations of herbicide tissue residues to physiological response measures were determined and the relationship was used to develop exposure-response models. Diquat and copper had a greater effect on plant tissue viability than was observed for 2,4-D. Diquat produced greater reductions in dissolved oxygen concentrations and pH values than 2,4-D or copper. Copper exposure had the least effect on these parameters. Exposure-response models developed for 2,4-D predicted effective control at plant tissue residues ranging from 4000 to 4700 mg/kg. Aqueous exposure concentrations necessary to produce effective control plant tissue residues ranged from 0.20 to 0.40 mg/L. Exposure-response models developed for diquat predicted effective control at plant tissue residues ranging from 225 to 280 mg/kg. Aqueous exposure concentrations necessary to produce effective control plant tissue residues ranged from 0.113 to 0.169 mg/L. Exposure-response models developed for copper predicted effective control at plant tissue residues ranging from 680 to 790 mg/kg. Aqueous exposure concentrations necessary to produce effective control plant tissue residues ranged from 0.32 to 0.64 mg/L. Model predictions for 2,4-D, diquat and copper were within 0.5 mg/L of the manufacturers' label recommendations for these herbicides. The use of laboratory microcosms in development of exposure-response models for diquat and copper produced results comparable to those using the larger-scale greenhouse systems. Diquat effectively controlled M. spicatum at lower tissue residues than 2,4-D or copper. In addition, initial aqueous exposure concentrations were also lower for diquat. Use of these models in field situations should be coupled with considerations of quantity of biomass present and environmental conditions, such as turbidity, in order to accurately calculate exposure concentrations necessary for effective tissue residues. Thus, the use of these models can be used to optimize the impact on the target species while minimizing exposure for nontarget species.
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Alford, Scott Buchannan. "Effects of Nonnative Eurasian Watermilfoil, Myriophyllum spicatum, on Nekton Habitat Quality in a Louisiana Oligohaline Estuary." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10807961.
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Native submerged aquatic vegetation (SAV) provides critical habitat for estuarine nekton. Relatively high nekton densities also are often associated with the nonnative, Eurasian Watermilfoil (Myriophyllum spicatum), a widely-distributed species in estuaries of the northern Gulf of Mexico. The goal of my study was to assess the habitat value of Myriophyllum with that of a common native SAV (Ruppia maritima) and SNB using two metrics (nekton density and growth of juvenile white shrimp Litopenaeus setiferus). Including estimates of vital rates such as growth together with density can give a more complete assessment. The nursery habitat provided by Myriophyllum for juvenile white shrimp appeared to match or exceed that of naturally occurring habitat types (Ruppia and SNB) in the oligohaline study area. Juvenile white shrimp densities in Myriophyllum (2.2 ? 0.47 m-2) were higher than those in Ruppia (1.0 ? 0.36 m-2). Similarly, white shrimp growth rates were higher in Myriophyllum (1.0 ? 0.07 mm TL d-1, 28.2 ? 2.83 mg d-1) than in Ruppia (0.6 ? 0.09 mm TL d-1, 14.1 ? 2.51 mg d-1). Myriophyllum also supported a nekton assemblage similar to that of Ruppia. Though differences were detected between SAV species, other factors derived from differences in SAV biomass may have driven differences in white shrimp growth rates and nekton densities. My study indicates that nonnative habitat forming species like Myriophyllum can provide an alternative to native habitat, though more research is needed to fully understand the mechanisms at work.
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Krayem, Maha. "Etude des effets de l'arsenic et du cuivre sur un macrophyte aquatique, Myriophyllum alterniflorum D.C. : évaluation des biomarqueurs pour la détection précoce de pollution." Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0131.
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L’utilisation des plantes aquatiques comme indicateurs de la qualité des eaux de rivière a débuté dès le XXème siècle. Parmi les macrophytes utilisés, le myriophylle à fleurs alternes, Myriophyllum alterniflorum a démontré dans plusieurs études sa capacité bioaccumulatrice des métaux et son intérêt en tant que bioindicatrice de qualité de l’eau. L’objectif de cette étude est d’identifier chez cette espèce des biomarqueurs sensibles pour la détection précoce de pollution d’une rivière par un métal, le cuivre et un métalloïde, l’arsenic. Pour atteindre cet objectif, un milieu synthétique dont la composition est représentative de la qualité des eaux de la rivière Vienne, a été préparé (milieu Vienne). Une fois les conditions opératoires maîtrisées, le développement du macrophyte est suivi dans trois milieux : un milieu témoin, un milieu contaminé en cuivre et un autre en arsenic avec des concentrations d’exposition au polluant de 100 µg/L pendant 21 jours. Durant cette période, des biomarqueurs physiologiques (activités respiratoires et photosynthétiques, potentiel osmotique), biochimiques (les concentrations en chlorophylle a, b et en caroténoïdes, les teneurs en malondialdéhyde, les phytochélatines) ont été analysés. Ces suivis ont été réalisés en système fermé dans des boites de culture de 400mL in vitro en tenant compte de la trophie du milieu (condition eutrophe et oligotrophe), puis en système recirculé dans des aquariums de 150 L, toujours dans le milieu Vienne, mais cette fois en se plaçant dans différentes conditions hydrodynamiques (zones turbulente, laminaire à une vitesse de 3 cm/s et calme)Alternate watermilfoil, Myriophyllum alterniflorum is an aquatic macrophyte presented in the rivers of the Limousin region in France whose potential for bioindication of metal pollution has been demonstrated. The objective of this study is to identify in this species sensitive biomarkers for the early detection of pollution in a river by a metal copper, and a metalloid, arsenic. To achieve this goal, a synthetic medium whose composition is representative of the water quality of the river Vienne, was prepared (Vienne medium). The composition of the medium studied is verified by ICP-MS and ion chromatography (IC). The development of the macrophyte was followed in a control medium, a copper contaminated medium and another contaminated with arsenic at a concentration of 100 µg/L for 21 days. During this period, the respiratory and photosynthetic activities of Myriophyllum alterniflorum, the concentrations of chlorophyll a, b and carotenoids, levels of malondialdehyde, osmotic potential, and phytochelatins were recorded. This monitoring has been made in a closed system (400mL culture boxes) taking into account the trophy of the medium (eutrophic and oligotrophic conditions), and then in a recirculating system (aquariums of 150 L) taking into account the hydrodynamic conditions (turbulent, laminar and quiet areas)
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Bauer, Nadine. "Dynamic of allelopathically active polyphenolic substances of Myriophyllum verticillatum L. and factors influencing allelopathic effects on phytoplankton." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://dx.doi.org/10.18452/16392.
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Durch die Freisetzung allelopathisch aktiver Substanzen können Makrophyten das Wachstum von Phytoplankton beeinflussen und damit den Klarwasserzustand von Flachseen stabilisieren. Umweltfaktoren beeinflussen allelopathische Effekte und wurden untersucht, um die Bedeutung allelopathischer Effekte im Ökosystem einzuschätzen. Der Gehalt allelopathisch aktiver polyphenolischer Substanzen zeigte Schwankungen bis zu einer Größenordung im Apikalmeristem von Myriophyllum verticillatum L innerhalb von vier Jahren 2004-2007, die nur teilweise durch den Nährstoffgehalt in der Pflanze erklärt wurden. Der Gehalt an Polyphenolen in der Trockenmasse der Pflanze korrelierte mit der Wachstumshemmung von Anabaena variabilis im Biotest und zeigte Maxima im Mai bis Juli wenn Konkurrenz mit dem Phytoplankton um Licht beim Wachstum zur Wasseroberfläche besteht. Mittels HPLC und MS gelang die Identifizierung von Hexahydroxydiphenoyl di- und -tri-galloylglucose Isomeren in den hauptaktiven Fraktionen des Pflanzenextraktes. Abiotische und biotische Einflüsse der Umwelt auf die Allelochemikalie z.B. photolytische und mikrobielle Umwandlungsprozesse führten bei der Modellsubstanz Tanninsäure (TA), die in Struktur und Funktion den gefundenen Allelochemikalien ähnelt, zur Bildung von refraktären hochmolekularen Verbindungen mit anhaltender allelopathischer Wirkung, die mittels LC-OCD den Huminstoffe zugeordnet wurden. Temperatur als weiterer Umweltfaktor beeinflusste artspezifisch die Reaktion der untersuchten Algen auf TA. Dabei waren die Art und das Ausmaß der Reaktion von der Anwesenheit von Bakterien abhängig. Bakterien der Gattung Pseudomonas wurden isoliert, die in der Lage waren, TA abzubauen und deren allelopathische Effekte zu mindern. Es konnten gezeigt werden, dassl Umwelteinflüsse auf die Allelochemikalie, mutualistische Phytoplankton-Bakterien Interaktionen und die Zusammensetzung der Bakteriengemeinschaft allelopathische Effekte qualitativ als auch quantitativ beeinflussten.Dissolved organic compounds released by macrophytes can have allelopathic effects on phytoplankton and thereby contribute to stabilize the clear water state of shallow lakes. Identifying factors influencing allelopathy enables evaluating allelopathic effects in the ecosystem.One factor is the temporal dynamic of allelopathically active substances and was investigated as total phenolic compounds(TPC). TPC ranged by an order of magnitude in apicals of Myriophyllum verticillatum L. during four years (2004-2007). Nutrient content partly explained TPC dynamic. The highest amounts of TPC in plant tissue corresponded to maximal growth inhibition of Anabaena variabilis in biotest from May to July when macrophytes compete with algae for light to grow to the water surface. Isomers of Hexahydroxydiphenoyl -di- and -trigalloylglucose identified by HPLC and LC-MS were found in the most allelopathically active fractions in the biotest. By the use of analytical and molecularbiological methods photolytic transformation and degradation by bacteria, changes in mutualistic interaction of bacteria and phytoplankton and shifts in bacterial community composition were identified as factors influencing the allelochemical and the phytoplankton response to TA quantitatively and qualitatively. Photolytic and microbial transformation formed long lasting allelopathically active degradation products of an allelopathic test substance, tannic acid (TA). Temperature was shown to influence the phytoplankton response to TA species specifically varying with presence or absence of bacteria. Bacteria community composition mediated phytoplankton response and specific bacteria as Pseudomonas sp.were able to degrade allelochemicals as TA and thereby lowered the allelopathic effect. Thus, allelopathic effects can be influenced by abiotic and biotic factors acting on the allelochemical, the target organisms and on mutualistic interaction between target organisms altering the outcome of allelopathic effects.
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McCann, Janet Helen. "The use of growth and membrane integrity assays as bioindicators of creosote effects in Myriophyllum spicatum L." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ27523.pdf.
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Weyl, Philip Sebastian Richard. "Friend or foe? : Resolving the status of the submerged macrophyte Myriophyllum spicatum L. (Haloragaceae) in southern Africa." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1017811.
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Myriophyllum spicatum L. (Haloragaceae), a submerged macrophyte, has been recorded in southern Africa since 1829, but only considered problematic as recently as 2005. In light of this, water resource managers are looking to control M. spicatum in southern African water bodies where it is problematic. Amongst control options available in South Africa, biological control is potentially the most cost effective and sustainable option for M. spicatum. However, there is a debate over the status of this plant in southern Africa with several authors reporting it as a native component of the aquatic ecosystem, while others argue that it has been introduced from Europe or Asia. The aim of this thesis is to use a multifaceted approach to resolve the status of M. spicatum, by studying aspects of its history, distribution, mechanisms of its adaptations, biotic interactions and genetic relationships in southern Africa. By resolving the status of this plant as either native or exotic, appropriate management strategies can be initiated for its control in situations where it is considered a problem.A review of the evidence collected from this thesis does not provide convincing evidence for the anthropogenic introduction of M. spicatum into southern Africa, and it is probably native to the region. The disjunct distribution as well as regular local extinctions of populations is relatively common for species that are at the edge of their range. The populations in southern Africa could thus be relics from a much wider distribution in the past. The development of local adaptations in southern Africa provides evidence for this and suggests that the populations have been isolated for a substantial period of time and have had a long evolutionary history in the region. The lack of specialist herbivores should suggest that M. spicatum has been introduced, but the complete lack of herbivores, including generalists, may weaken that argument. The lack of herbivores could be a result of something inherent in the plant, irrespective of a lack of evolutionary history in the region. The genetic evidence suggests a European origin, but is characteristic of a population (southern Africa as a whole) that has been isolated for a considerable time. Despite the findings of this research, M. spicatum is considered problematic in southern Africa and warrants control in certain systems. Whether or not biological control should be a component of the management strategy is open to further debate. The benefits in a southern African context may outweigh the risks, based on the specificity of the biological control agent proposed. However, the perceived negative impacts of M. spicatum are likely to be a symptom of a more serious underlying cause, such as nutrient loading and changes in land use patterns. Therefore the control of this native species is a water resource management issue and not a biological control issue.
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Roshon, Roxana D. "A toxicity test for the effects of chemicals on the non-target submersed aquatic macrophyte, Myriophyllum sibiricum Komarov." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ33321.pdf.
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Ozkan, Korhan. "Role Of Nitrogen In Submerged Plant Development In Mediterranean Climatic Zone - A Mesocosm Experiment." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610083/index.pdf.
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The effects of increasing nitrogen and phosphorus loading on submerged macrophyte development was tested in a mesocosm experiment for three months. Experiment consisted of three NO3-N loadings with factorial of two PO4-P loadings in a fourfold
replicated design. Twenty four enclosures placed at one meter depth were isolated from the lake but kept open to sediment and atmosphere. Each enclosure stocked with ten Myriophyllum spicatum shoots with underyearling fish to reduce zooplankton grazers.
Biweekly sampling and weekly nutrient additions were performed for three months. Mean total nitrogen (TN) concentrations sustained in nitrogen treatments through out the experiment were 0.52, 1.99, 8.07 mg/l. Both phosphorus treatments
converged to a mean concentration below the targeted level, ranging between 0.05-0.1 mg/l TP. In comparison to mesocosm studies in temperate lakes, higher assimilation rates for nutrients were observed in Lake Pedina. Due to extraordinarily high evapotranspiration and drought in 2007, the water level decreased 0.6 m in enclosures.
Total macrophyte biomass remained indifferent to nutrient treatments with continuous growth and failed to validate any direct or indirect negative effect of increasing nutrient concentrations. Phytoplankton biomass differed significantly among factorial treatments but remained low, while periphyton biomass differed among nitrogen treatments. In comparison with other studies the phytoplankton biomass remained low and the periphyton biomass became high for reference TP concentrations, indicating a competitive advantage of periphyton over phytoplankton on nutrient utilization in the enclosures. Zooplankton:phytoplankton biomass ratio was low throughout the experiment and zooplankton community mainly consists of smaller species, reflecting high predation pressure.
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Heine, Simon [Verfasser]. "Development and specification of a toxicokinetic and toxicodynamic growth model of Myriophyllum spicatum for use in risk assessment / Simon Heine." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1065353502/34.
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Delmail, David. "Contribution de Myriophyllum alterniflorum et de son périphyton à la biosurveillance de la qualité des eaux face aux métaux lourds." Limoges, 2011. http://www.theses.fr/2011LIMO330C.
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L‘utilisation des plantes dans la biosurveillance de la qualité des eaux courantes lors des études écotoxicologiques, est un domaine en plein essor. Myriophyllum alterniflorum est un macrophyte aquatique méconnu dont l‘utilisation potentielle en tant que biomarqueur est évaluée vis-à-vis des pollutions au cadmium et au cuivre. De même, les réponses communautaires de son périphyton épiphyte sont considérées. Après le développement de la culture in vitro de M. Alterniflorum, un protocole de réintroduction en nature des clones est établi. Cela permet d‘étudier en laboratoire et sur le terrain, la toxicité de ces métaux lourds chez ce macrophyte ainsi que sa réponse antioxydante. Cette perturbation provoque l‘apparition d‘une nouvelle structure anatomique, un double endoderme foliaire, réduisant le stress hydrique. De plus, quatre biomarqueurs spécifiques de la contamination au cuivre sont mis en évidence in situ : l‘ascorbate peroxydase, la glucose-6-phosphate déshydrogénase, la vitamine E et le malondialdéhyde. La biodiversité du périphyton associé à M. Alterniflorum apporte des informations complémentaires sur la contamination en cadmium et en cuivre des milieux par la présence de groupes aux affinités écologiques propres. En outre, la dynamique métacommunautaire des taxa les plus représentatifs souligne l‘importance de la restauration écologique du support végétal dans les environnements perturbés pour la pérennité de ces microorganismes. Macrophyte et périphyton contribuent donc efficacement à la biosurveillance, et ils sont exploitables pour la gestion des espaces naturels et les études de santé publique en accord avec les directives européennes et nationales sur l‘eauUsing plants to biomonitor stream water quality in ecotoxicological surveys is a promising way. Myriophyllum alterniflorum is a poor-known aquatic macrophyte which biomarker potential is evaluated during cadmium and copper pollutions. The responses of its periphyton communities are also studied. After establishment of the in vitro culture of M. Alterniflorum, a protocol is defined for clone reintroduction. It allows comparative laboratory and field studies to assess the toxicity of heavy metals on M. Alterniflorum and its antioxidant responses. A new anatomical feature reducing the water stress appears in leaves, as a double endodermis. Moreover, four copper-specific biomarkers are evidenced in in situ conditions: ascorbate peroxidase, glucose-6-phosphate dehydrogenase, vitamin E and malondialdehyde. Using the occurrence of groups with specific ecological affinities, the periphyton biodiversity brings highlights about cadmium and copper contamination. Furthermore, in a metacommunity approach, the dynamics of the most representative taxa underlines the importance of the plant-substrate restoration to ensure the continued survival in disturbed environments. Macrophyte and periphyton appear as essential in biomonitoring, and they are useful for the management of natural habitats and for public health policies according to the European and national water directives
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Santos, Mariana Gonzaga dos. "Decomposição aeróbia de Myriophyllum aquaticum (Vell.) Verdc. e caracterização limnológica na bacia hidrográfica do rio do Monjolinho (São Carlos, SP, Brasil)." Universidade Federal de São Carlos, 2009. https://repositorio.ufscar.br/handle/ufscar/1949.
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Previous issue date: 2009-06-02Universidade Federal de Minas Gerais
The oxidative aerobic processes contribute with large amounts of nutrients in dissolved and particulate forms for the metabolism microbial water. In that context, this study described the oxygen consumption kinetics during the aerobic mineralization of Myriophyllum aquaticum and also evaluated the possible effects of nutrients addiction, the chemical composition and temperature on the decomposition. The aquatic macrophyte was collected in the coastal region of the Monjolinho reservoir (220 00' S and 47054' W; SP, Brazil). In the laboratory part of the plant fragments were subjected to leaching for extraction of the dissolved organic matter (DOM). In the laboratory, part of the plant fragments was subjected to leaching to extract the particulate fraction (POM). The mineralization chambers were set up (n = 96) with different N and P concentrations, entire detritus or lignocellulosic matrix (i.e. fibers) in two phenological stages (senescent or green) under two temperature (16 and 25 ºC), totaling 32 treatments. The concentrations of dissolved oxygen (DO) were determined periodically in the chambers for 80 days. The results were adjusted to a kinetic model of first-order. Different concentrations of N and P did not interfere in the microbial metabolism when the experiments with full detritus and lignocellulosic matrix were analyzed separately. Moreover, in experiments that include the mineralization of macrophytes under natural conditions (with reservoir water), was favoring the mineralization rather than immobilization. However, the independent analysis of the concentrations of N and P showed that the same condition of temperature and type of fragment (green or senescent), the kD was approximately 2 times greater in treatments with full detritus for those with only lignocellulosic matrix, which showed higher C: P and smaller quantities of lignin in their original chemical composition. The Q10 has shown similarities between the treatments, regardless of chemical composition (entire or fibers), but differences in relation to the plant phenological stage (ranging from 1.75 to 2.06). Regarding the stoichiometry O/N was an expense of greater oxygen for nitrification in treatments with full litter (mean = 1%) compared to treatment with lignocellulosic matrix (mean = 0.6%). The quality of detritus was the most important variable in the mineralization of macrophytes the temperature has served as a secondary factor.
Os processos oxidativos aeróbios contribuem com grande quantidade de nutrientes nas formas dissolvida e particulada para o metabolismo da microbiota aquática. Nesse contexto, este estudo descreveu as cinéticas de consumo de oxigênio durante a mineralização aeróbia de Myriophyllum aquaticum, avaliando os possíveis efeitos da adição de nutrientes, composição química do detrito e da temperatura na decomposição. A macrófita aquática foi coletada na região litorânea do reservatório do Monjolinho (220 00' S e 470 54' O; SP, Brasil). Em laboratório parte dos fragmentos das plantas foram submetidos à lixiviação para extração da fração dissolvida (MOD). Foram montadas câmaras de decomposição (n = 96) com diferentes concentrações de N e P, contendo detrito íntegro ou matriz lignocelulósica (i.e. fibras) em dois estágios fenológicos (verde ou senescente) e submetidas a duas condições de temperatura (16 e 25 ºC), totalizando 32 tratamentos. As concentrações de oxigênio dissolvido (OD) foram determinadas periodicamente nas câmaras durante 80 dias. Os resultados foram ajustados a um modelo cinético de primeira-ordem. As diferentes concentrações de N e P não interferiram no metabolismo microbiano quando os experimentos com detrito íntegro e matriz lignocelulósica foram analisados separadamente. Por outro lado, nos experimentos que contemplaram a mineralização da macrófita sem enriquecimento com N e P (água do reservatório), houve o favorecimento da mineralização em detrimento da imobilização. Porém, a análise independente das concentrações de N e P mostraram que numa mesma condição de temperatura e tipo de fragmento (verde ou senescente), o kD foi aproximadamente 2 vezes maior nos tratamentos com detrito íntegro em relação aqueles somente com matriz lignocelulósica, que apresentou maior relação C:P e menores quantidades de lignina em sua composição química inicial. O Q10 mostrou similaridade entre os tratamentos, independente da composição química (integral ou fibras), porém, diferença em relação ao estágio fenológico da planta (variaram de 1,75 a 2,06). Com relação à estequiometria O/N houve um gasto maior de oxigênio para a nitrificação nos tratamentos com detritos íntegros (média = 1%) em relação aos tratamentos com matriz lignocelulósica (média = 0,6%). A qualidade do detrito constituiu se na variável mais importante na mineralização da macrófita, já a temperatura atuou como um fator secundário.
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Nuttens, Andréïna. "Étude des effets de l'interaction entre polluants et ressources sur Myriophyllum spicatum grâce à une approche couplant écotoxicologie et écologie chimique." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0143/document.
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La contamination simultanée des écosystèmes aquatiques par des polluants et des nutriments est un problème majeur dont les effets sur les macrophytes sont encore méconnus. L'objectif de cette thèse était d'étudier les effets de deux types de polluants : herbicides et éléments trace métalliques (ETM), en combinaison avec des ressources variables (azote, phosphore, ou carbone) sur Myriophyllum spicatum, en utilisant des paramètres provenant de l'écologie chimique et de l'écotoxicologie. Les tests ont montré des effets contrastés des herbicides sur la plante, mais pas d'effet des ETM. Dans tous les cas, les modifications de ressources (nitrate, ratio N:P ou saccharose) ont induit des effets importants sur la physiologie et la stœchiométrie de la plante, pouvant altérer ses réponses à un stress supplémentaire comme les polluants. Ces résultats suggèrent qu'un déséquilibre des ressources en présence de polluants pourrait modifier leurs effets sur les macrophytes, et soulignent également la nécessité d'ajouter des paramètres plus informatifs dans les tests afin de répondre aux enjeux du stress multiple et améliorer l'évaluation du risque environnementalSimultaneous contamination of aquatic ecosystems by pollutants and nutrients is a major problem whose effects on macrophytes are still unknown. The objective of this thesis was to study the effects of different pollutants, herbicides and trace metal elements (TME), in combination with varying resource availability (nitrogen, phosphorus, or carbon) on Myriophyllum spicatum, using parameters from chemical ecology and ecotoxicology. Tests showed contrasting effects of herbicides, but no effects of the TME. In all cases, resource modifications (nitrate, N:P ratio or sucrose) induced significant effects on the physiology and stoichiometry of the plant, which might alter its response to additional stress like pollutants. These results suggest that an imbalance of resources in the presence of pollutants may lead to unforeseen changes in the combined effects on macrophytes, and also highlight the need to add more informative parameters in tests to meet the challenges of multiple stress and improve environmental risk assessment
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King, Kimberly L. P. "Effects of exposure to Eurasian Milfoil (Myriophyllum spicatum) on the growth and development of Xenopus laevis and the Columbia spotted frog (Rana Lutriventris)." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Fall2007/K_King_112607.pdf.
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Tront, Jacqueline Marie. "Plant Activity and Organic Contaminant Processing by Aquatic Plants." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5234.
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This research explored fate of organic contaminants in aquatic plant systems through (i) experimental development of relationships to describe sorption, uptake and enzymatic processing of contaminants by plants and inhibition of aquatic plants by contaminants and (ii) incorporation of experimental relationships into a conceptual model which describes contaminant fate in aquatic plant systems. This study focused on interactions of aquatic plants L. minor and M. aquaticum with halogenated phenols. 2,4,5-trichlorophenol (2,4,5-TCP) and 2,4-dichlorophenol (2,4-DCP) are precursors for the highly toxic and heavily applied herbicides 2,4,5-T and 2,4-D and were examined in detail. Chlorophenols are generally resistant to microbial degradation, a property which may limit microbial remediation options as effective alternatives for clean up of contaminated sites.
Relationships for fundamental interactions between plants and contaminants that dictate uptake, enzymatic processing and sequestration of contaminants by aquatic plants were established. An assay which quantified production of oxygen by plants was developed to quantify plant metabolic activity and inhibition. Uptake of chlorinated phenols depended on plant activity and aqueous phase concentration of contaminant in the protonated form. Therefore, plant activity, contaminant pKa and media pH were established as critical parameters controlling rate of contaminant uptake. A conceptual model was developed which incorporated plant activity and inhibition into a mathematical description of uptake of organic contaminants by aquatic plants. The conceptual model was parameterized using experimental data delineating effect of plant activity, inhibition and speciation on contaminant uptake and the model was verified using independently gathered data. Experimentation with radio-labeled chlorinated phenols established that contaminants were sequestered internal to plants by plant enzymatic processing. 19F NMR was established as a technique to quantify transformation and conjugation products internal to plants and contaminant assimilation by plants and demonstrated that multiple metabolites containing the parent compound were present and quantifiable internal to plants. Finally, fate of plant-sequestered contaminants in an anaerobic bioassay was examined using Desulfitobacterium sp. strain Viet1.
The results of this study address the role of aquatic plants in sequestration of contaminants in surface waters that indicate the potential and limitations of use of aquatic plants in natural and engineered treatment systems.
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Bauer, Nadine [Verfasser], R. [Akademischer Betreuer] Ehwald, S. [Akademischer Betreuer] Hilt, and N. [Akademischer Betreuer] Kamjunke. "Dynamic of allelopathically active polyphenolic substances of Myriophyllum verticillatum L. and factors influencing allelopathic effects on phytoplankton / Nadine Bauer. Gutachter: R. Ehwald ; S. Hilt ; N. Kamjunke." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://d-nb.info/1017494827/34.
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Varja, Knežević. "Potencijal oporavka akvatičnih vrsta makrofita Lemna minor Linnaeus (Lemnaceae, 1753) i Myriophyllum aquaticum (Vellosco) Verdcourt (Haloragaceae, c. 1880), od toksičnog stresa nakon izlaganja odabranim herbicidima i njihovim smešama." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2017. https://www.cris.uns.ac.rs/record.jsf?recordId=104772&source=NDLTD&language=en.
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Akvatični ekosistemi su izloženi simultanom delovanju velikog broja potencijalnotoksičnih supstanci u vremenski i prostorno promenljivim uslovima u životnoj sredini.U ovoj disertaciji je poređen efekat pojedinačnih herbicida – atrazina, izoproturona itrifluralina – sa efektima njihovih smeša u testu sa Lemna minor. Odabrane su smeše sa sličnim (dvo-komponentna smeša atrazina/izoproturona) i različitim (dvo-komponentna smeša atrazina/trifluralina i izoproturona/trifluralina, kao i tro-komponenta smeša) mehanizmom toksičnog dejstva. Kako se sve češće ističeneophodnost sagledavanja ne samo potencijalnih razlika u toksikološkoj osetljivosti jedinki/populacija, već i razlika u efikasnosti njihovog oporavka, u ovoj disertaciji, je određen potencijal oporavka vrste L. minor nakon izloženosti navedenim pojedinačnim herbicidima/smešama. Ispitano je da li prirodna organska materija (POM), koja je u testovima na akvatičnim makrofitama simulirana preko huminskih materija (HM) u realnim koncentracijama u površinskim vodama, modulira toksičnost atrazina i 2,4 D, i njihove dvo-komponentne smeše, u testu sa L. minor, odnosno izoproturona, dikambe i njihove dvo-komponentne smeše, u testu sa Myriophyllum aquaticum. Utvrđen je stepen odstupanja između empirijske toksičnosti svih navedenih smeša herbicida, sa teorijski očekivanim vrednostima na osnovu modela adicije koncentracija (CA), u testovima na obe vrste akvatičnih makrofita. Ispitano je da li se postojeći CA model može koristiti i za procenu toksičnog dejstva smeša uzimajući u obzir integralno i podatke o oporavku eksponiranih vrsta akvatičnih makrofita. Rezultati u ovoj disertaciju su pokazali da modifikacijom laboratorijskog protokola gde se oporavak akvatičnih makrofita pratio tokom dodatnih pet/sedam dana testa nakon sedmodnevne ekspozicije se mogu dobiti ekološki relevantni podaci o odloženom toksičnom dejstvu pojedinačnih supstanci/smeša. U testu sa atrazinom i izoproturonom, kao pojedinačnim supstancama, je uočen efikasan oporavak vrste L.minor. Sa druge strane, u slučaju trifluralina i 2,4 D u periodu oporavka je zabeleženo odloženo toksično dejstvo. Na primeru trifluralina i 2,4 D se pokazalo da standardnitestovi toksičnosti, zanemarujući podatke o potencijalu oporavka, mogu potceniti realan rizik od pesticida. U slučaju drugog sintetičkog auksina, dikambe, pri izabranoj seriji koncentracija nije zabeleženo toksično dejstvo na vrstu L. minor. Odgovor vrste L. minor na dejstvo dvo-komponentne smeše atrazina i izoproturona je sličan onom zabeleženom u testu sa navedenim herbicidima, kao pojedinačnim supstancama. Zabeležen je efikasan oporavak biljne kulture, nezavisno od primenjene koncentracije herbicida u smeši. Sa druge strane, oporavak vrste L. minor nakon izloženosti dvo- i tro-komponentnim smešma sa trifluralinom zavisi od primenjene koncentracije herbicida u smeši i zabeležen je jedino u tipu smeša gde su koncentracije pojedinačnih herbicida bliske relativno bliske mogućim koncentracijama herbicida u životnoj sredini. Povećanje toksičnosti pojedinačnih supstanci/smeša uslovljeno prisustvom HM je primećena u slučaju atrazina, 2,4 D i njihove dvo-komponentne smeše, u testu na vrsti L. minor, odnosno dikambe u testu sa M. aquaticum. Suprotan efekat HM je primećen u testu sa M. aquaticum u slučaju izoproturona i dvo-komponentne smeše izoproturona i dikambe, jer je zabeležena niža toksičnost u prisustvu HM. Iako određene razlike u toksičnosti između ispitivanih test tretmana u prisustvu i odsustvu HM postoje, one nisu bile statistički značajne. Oporavak akvatičnih makrofita od efekta dvo-komponentnih smeša, u prisustvu/odsustvu HM, zavisi od primenjene koncentracije herbicida u smeši. Izuzetak čini dvo-komponentna smeša atrazina i 2,4 D, u testu sa L. minor, gde nije došlo do oporavka biljne kulture ni u jednom od tipova smeša u prisustvu HM. Generalno, uočena je dobra saglasnost između empirijske i predviđene toksičnosti, na osnovu CA modela, nezavisno od mehanizma toksičnog dejstva supstanci prisutnih u smeši ili prisustva odnosno odsustva HM. Odstupanje od adivnosti je zabeleženo jedino u testu sa L. minor u slučaju dvo-komponentnih smeša sa trifluralinom (atrazin+trifluralin i izoproturon+trifluralin), gde se ispostavilo da CA model u određenoj meri potcenjuje dejstvo navedenih smeša, što upućuje na pojavu sinergističkih interakcija između supstanci. Pokazano je i da se CA model može alternativno koristiti za procenu toksičnosti odabranih smeša, na osnovu integralnih saznanja o osetljivosti i potencijalu oporavka eksponiranih jedinki/populacija, pod uslovom da su dostupni takvi podaci za pojedinačne susptance koje ulaze u sastav smeše.Aquatic ecosystems are exposed to a simultaneous effect of a large number of potentially toxic substances in a temporally and spatially variable conditions in the environment. In this doctoral thesis, the effect of the individual herbicides atrazine,isoproturon, and trifluralin was compared with the effect of their mixtures, in the test with Lemna minor. Mixtures with a similar (binary mixture of atrazine/isoproturon) and dissimilar (binary mixtures with atrazine/trifluralin, soproturon/trifluralin, and ternary mixture) mode of action were selected. There is a clear need to take into account not only the differences in toxicological sensitivity of the exposed individuals/populations, but also the differences in their recovery efficiency.Therefore, in this thesis, L. minor recovery potential was assessed after the exposure to the individual herbicides/mixtures. It was tested whether a natural organic matter (NOM), which was, in these tests, simulated through the humic matter (HM) used in real concentrations in surface waters, modulated the toxicity of atrazine, 2.4 D, and their binary mixture, in tests with L. minor, and disoproturon, dicamba and their binary mixture, in tests with Myriophyllum aquaticum. The deviation between the empirical toxicity of the herbicidal mixtures and the predicted toxicity based on the concentration addition (CA) model was determined. It was also examined whether the current CA model can be used to predict mixture oxic effects by taking into account the information about the plant recovery potential as well. The results showed that by modifying laboratory protocols, where the recovery of aquatic macrophytes was followed for additional five/seven days after the seven day exposure, environmentally relevant data on delayed toxic effects of the individual substances/mixtures can be obtained. In the tests with atrazine and isoproturon as individual substances, the efficient recovery of L. minor was observed. On the other hand, in the case of trifluralin and 2,4 D, delayed toxic effects were recorded during the recovery period.In the test with trifluralin and 2.4 D, it was shown that standard toxicity tests may underestimate the real risk of pesticides by not considering data on recovery. In the case of another synthetic auxin, dicamba, toxic effect on L. minor was not reported in the selected concentration series. The response of L. minor after the exposure tobinary mixtures of atrazine and isoproturon was similar to the one recorded in the tests with these herbicides as the individual substances. Efficient plant recovery was recorded, regardless of the applied herbicide concentration in the mixture. On the other hand, the recovery of L. minor after exposure to binary and ternary mixtures with trifluralin depended on the applied herbicide concentration in the mixture, and was recorded only in the type of mixtures where the concentrations of the individual herbicides were close to the possible concentration of these herbicides in the environment. The toxicity increase of the individual substances/mixtures, influenced by the presence of HM was observed in the case of atrazine, 2,4 D, and their binary mixture, in the test with L. minor, that is, dicamba, in the test with M. aquaticum. In the test with M. aquaticum, the opposite effect was observed in the case ofisoproturon and binary mixture of isoproturon and dicamba, due to lower toxicity being recorded in the presence of HM. Even though some differences in toxicity between the test treatments in the presence and absence of HM were recorded, the differences were not statistically significant. The recovery of macrophytes after the exposure to the binary mixtures, in the presence/absence of HM, depended on the applied herbicide concentration in the mixture. The exception was noticed in the test with L. minor in the binary mixture with atrazine and 2,4 D, where no recovery was recorded in any type of the mixture in the presence of HM. Generally, there was a good agreement between the empirical toxicity and the predicted one based on the CA model, regardless of the mode of action of the toxic substances present in the mixture, or presence/absence of HM. The deviation from additivity was recorded only in the test with L. minor in the case of the binary mixture with trifluralin (atrazine/trifluralin and isoproturon/trifluralin), which meant that the CA model underestimated the mixture effect to a certain extent, suggesting that synergistic interaction between the substances might have appeared. It was also shown that the CA model may alternatively be used for the assessment of toxicity of the selected mixture, based on the integrated knowledge of both sensitivity and recovery potential of the exposed species/populations, providing that such information about individual substances in the mixture exists.
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Fordham, Colin Justin. "A spatial and temporal analysis of the changes in alien macrophyte communities and a baseline assessment of the macroinvertebrates associated with Eurasian watermilfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal River." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005455.
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The majority of South Africa’s fresh water (lotic and lentic), is eutrophic and this has resulted in water hyacinth, Eichhornia crassipes (C.Mart.) Solms. (Pontederiaceae) becoming South Africa’s most damaging aquatic macrophyte. Recently however, concerns have also been voiced over the presence of highly invasive submerged macrophyte species, such as Eurasian water-milfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal River. Interaction studies between floating and submerged macrophytes have shown that floating macrophyte dominance restricts light penetration into the water column shading out submerged macrophytes while submerged macrophyte dominance reduces nutrient availability in the water column limiting floating macrophyte growth. This cycle ensures that these species cannot coexist in the same habitat for extended periods of time. The aims of this thesis were to: 1. Investigate changes in the historical and current macrophyte dominance in the Vaal River 2. Determine whether these changes could be attributed to stochastic events, such as floods and herbicide control measures. 3. The physio-chemical conditions of the water column, and whether pressure from herbivory by macroinvertebrates had possibly influenced Eurasian water-milfoil’s ability to dominate. Spatial and temporal analysis of satellite imagery revealed that water hyacinth and submerged macrophyte species dominated different regions of the study area over different periods of time from 2006 to 2010. This was significantly correlated with nitrate concentrations of the water column. One of the lower Vaal River Water Management Areas (WMA) had changed from a water hyacinth dominated state in 2006 to an alternative submerged macrophyte dominated stable state in 2008. It was concluded that this change could be attributed to: a stochastic flooding event in 2006; perturbation from integrated control measures implemented against water hyacinth; and low nitrate concentrations of the WMA. The lack of any substantial macroinvertebrate herbivory pressure or control measures implemented against Eurasian water-milfoil, compared to similar surveys conducted in the U.S.A. and its native range in Eurasia was shown to contribute to its dominance. Future successful integrated control programmes, including biological control against Eurasian water-milfoil, could provide the perturbation required to restore the ecosystem. However, without the reduction in nitrate concentration levels, water hyacinth will remain the dominant stable state of the rest of the Vaal River.
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Curtis, Amanda N. "Non-target Impacts of Chemical Management for Invasive Plants on Lithobates Pipiens Tadpoles." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1416525356.
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Rust-Smith, Michael (1990-2010). "Oxygen Production During Photosynthesis in Aquatic Plant Myriophyllum hippuroides." 2009. http://hdl.handle.net/2429/8042.
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In this experiment western milfoil, a common fresh water plant, was used to determine the rate of oxygen production during photosynthesis. The rate was determined based on the amount of gaseous oxygen produced by a given number of plants over a period of time. The combined results of ten trials yielded an average oxygen production rate of 0.57μmol/m²/s ± 0.016μmol/ m²/s. This rate is comparable to those of various other aquatic plants, which vary from 0.1μmol/m²/s to upwards of 5μmol/m²/s [2].
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Lavoie, Martin. "L'utilisation du charançon pour le contrôle biologique du myriophylle à épis." Mémoire, 2010. http://www.archipel.uqam.ca/2790/1/M11280.pdf.
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Les démarches pour instaurer le projet pilote du contrôle biologique du myriophylle à épis, Myriophyllum spicatum, par le charançon, Euhrychiopsis lecontei, au lac Supérieur dans les Laurentides, ont débuté en 2003. C'est une initiative de l'association du lac Supérieur, qui consiste à trouver une solution à ce problème de plante aquatique envahissante. Le myriophylle à épis, est une plante aquatique exotique qui envahit les plans d'eau nord-américains, et qui, en plus de causer des impacts environnementaux substantiels, est associé à des problèmes économiques. À notre connaissance, le projet pilote de contrôle biologique du lac Supérieur est une première canadienne. Le travail de terrain a démarré à l'été 2005. Le projet pilote a consisté à inoculer successivement 10 000 charançons par année, dans les herbiers de myriophylle à épis, pendant une période de trois années, soit aux étés 2005, 2006 et 2007. Selon nos hypothèses, le lâcher inoculatif de 30 000 charançons au lac Supérieur, sur une période de trois ans, devrait permettre d'augmenter significativement la densité des populations résidentes de charançons. Ce lâcher inoculatif devrait également contribuer à réduire le nombre de tiges au mètre carré de myriophylle à épis dans les herbiers présents au lac Supérieur. Finalement, l'augmentation de la population de charançon et la diminution des herbiers de myriophylle à épis, devraient contribuer à favoriser la croissance des plantes aquatiques indigènes présentes dans le lac. Afin d'évaluer le potentiel du charançon aquatique indigène, E. lecontei, comme agent de contrôle biologique, nous avons comparé les résultats obtenus entre quatre quadrats qui ont été inoculés, et deux autres quadrats qui ont servi de sites témoins, sans inoculation de charançons. Des suivis mensuels ont été effectués durant ces trois périodes estivales afin d'évaluer la population de charançons, la densité des herbiers de myriophylle à épis et de faire le suivi des communautés de macrophytes indigènes. Les résultats démontrent que la population de charançon a légèrement augmenté dans les quadrats inoculés par rapport aux quadrats témoins, mais sans avoir eu l'effet de dispersion des insectes à l'ensemble du lac. La densité de certains herbiers de myriophylle à épis inoculés a diminué, mais le phénomène ne s'est pas généralisé. Finalement, ces changements n'ont pas été assez importants pour que la composition des communautés de plantes aquatiques indigènes change de façon significative. Les trois premières années de ce projet pilote de contrôle biologique démontre que certains changements localisés sont apparus au lac Supérieur, mais sans qu'il y ait un véritable processus de contrôle biologique. Nous allons devoir travailler davantage à comprendre quels sont les facteurs limitatifs au processus de contrôle biologique, que ce soit la prédation par les poissons ou encore la rigueur de notre climat. D'autres expériences devraient être menées afin de pouvoir conclure définitivement si le charançon E. lecontei détient ou non un avenir prometteur en tant qu'agent de lutte biologique de la plante aquatique M spicatum. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Plantes envahissantes, Macrophytes, Myriophyllum spicatum, Euhrychiopsis lecontei, Contrôle biologique, Charançon.
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Mikšová, Martina. "Ovlivnění enzymatické aktivity způsobené mědí a kadmiem u vodní rostliny Myriophyllum alterniflorum DC." Master's thesis, 2008. http://www.nusl.cz/ntk/nusl-291031.
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This thesis concerns with the effects of heavy metals on plants and is a part of a broader research on biomarkers of oxidative stress in aquatic plants in the Department of Pharmaceutical Botany of Faculty of Pharmacy in the University of Limoges. Experimental organism was an aquatic plant Myriophyllum alterniflorum DC (alternate water milfoil) that was collected in the upper stream of the river Vienna. Samples were cultivated in the increasing concentrations of copper and cadmium (0mM, 0,25mM, 0,5mM, 0,75mM) for 1, 3 and 6 days. On account of time and chemical products insufficiency only several analyses of plants treated with copper were carried out. Catalase is one of the enzymes integrated in the antioxidative defence system. It decomposes H2O2 into water. During the time catalase activity gradually increased up to 0,5mM. 0,75mM showed the maximum after the third day. When comparing different copper concentrations after the same cultivation period the highest activity was observed in 0,25mM in the first day and in 0,50mM the third and sixth day. Myriophyllum alterniflorum DC as other aquatic plants exhibits the heavy metal accumulation ability increasing in time and higher copper concentrations. On the contrary, decreasing time and concentration dependence was observable in measurements of...
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Maezo, María José. "Interaction entre deux espèces envahissantes : l'écrevisse à taches rouges et le myriophylle à épis." Mémoire, 2008. http://www.archipel.uqam.ca/1687/1/M10628.pdf.
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Les espèces envahissantes constituent une menace de plus en plus importante pour la biodiversité et le fonctionnement des écosystèmes. Plusieurs milieux peuvent être sujets à de multiples introductions et prédire les impacts de celles-ci lorsqu'elles se retrouvent ensemble est donc devenu un des plus importants défis pour les écologistes. Le but de cette étude est de déterminer si les impacts individuels de deux espèces envahissantes, le myriophylle à épis (Myriophyllum spicatum) et l'écrevisse à taches rouges (Orconectes rusticus), peuvent être affectés par leur interaction. A priori, O. rusticus pourrait diminuer les impacts du myriophylle en réduisant son abondance, cependant il pourrait aussi favoriser sa dispersion en coupant des fragments. Deux approches ont été utilisées pour évaluer l'importance de ces interactions. Premièrement, une expérience in situ a été réalisée pour quantifier la production de fragments et la réduction de la biomasse des myriophylles par les écrevisses. Différentes densités d'écrevisses ont été ajoutées à seize cages installées dans un même lit de myriophylle. Les fragments produits ont été comptés chaque semaine et la biomasse restante a été mesurée à la fin de l'expérience. Les résultats ont démontré que des densités d'écrevisses moyennes et élevées augmentaient la production de fragments alors que seules des densités d'écrevisses élevées réduisaient significativement la biomasse. L'effet de faibles densités d'écrevisses sur les myriophylles était négligeable. Un échantillonnage de 132 sites au lac Pemichangan, Québec, a ensuite été mené pour évaluer les caractéristiques et la superposition des habitats des deux espèces. Une analyse de redondance a démontré qu'il y avait peu de chevauchement dans leur distribution, l'interaction devrait donc être négligeable. Les expériences indiquent que les écrevisses pourraient avoir un impact sur les myriophylles dépendamment de leur densité, cependant, au lac Pemichangan, l'impact des deux espèces ne sera pas affecté par leur interaction. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Espèces envahissantes, Macrophytes, Écrevisses, Myriophyllum spicatum, Orconectes rusticus, Zone littorale.
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Roan, Po-Hsun, and 阮柏勳. "Study of Purifying Effluent of Three Stages Wastewater Treatment System by Aquatic Plants─Myriophyllum verticillatum." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/3sj557.
Full textAbstract:
碩士國立臺灣大學
生物環境系統工程學研究所
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In Taiwan, three-stage wastewater treatment system is widely used in farm management to purify livestock wastewater before discharged into the rivers. However, discharged water usually do not fit the standard of Taiwan pollution policy implemented recently, which is caused by improper operation of treatment system, antique equipment or environment change.For protecting environment and avoiding punishment, planting aquatic plants in three-stage wastewater treatment system to remove excessive nutrients is an inexpensive method which could make up for the shortage of the treatment system and improve the environment. In this study, Myriophyllum verticillatum was taken as a research subject because it not only grows rapidly but also owns high purify ability and the tolerance of polluted water. The experiments were conducted to study the purify ability of Myriophyllum verticillatum. Various nutrients’ concentrations of water were poured into plastic containers with Myriophyllum verticillatum. Recorded the variations of nutrients’ concentrations regularly to estimate the purify ability. According to the result, Myriophyllum verticillatum could remove 191.54 to 542.17 mg ammonium and 7.18 to 39.76 mg total phosphorus per kilogram per day . Myriophyllum verticillatum would be planted at appropriate tanks of three-stage wastewater treatment system to reduce the load of treatment system and improve the quality of discharged water.
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Hrdinová, Magdalena. "Zhodnocení cytotypové a morfologické variability spolu s mírou hybridizace u rodu stolístek (Myriophyllum) na území ČR a sousedních států." Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-353800.
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Myriophyllum L. (watermilfoil) belongs to one of the most invasive genus of the Northern Hemisphere. The three most agressive species, one of which is native to Europe (M. spicatum), are widespread throughout the majority of United states and two of them (M. aquaticum and M. heterophyllum) are becoming invasive in several Europaean countries as well. Therefore, Europaean populations of both native and invasive species, represents ideal place where to study processes which account for watermilfoils' invasivness. In this study, flow cytometry, morphometric analyses and germination experiments were employed to evaluate cytotype and morphological variability of Myriophyllum along with its potential to hybridize and propagate generatively. Five ploidy levels were detected in Europe, however no ploidy variability has been found within any species except for M. sibiricum (hexaploids and nonaploids) and one population of M. aquaticum (hexaploids and oktoploids). Flow cytometry proved to be useful tool for purposes of distinguishing species of different ploidy level and their potential hybrids. Nevertheless, the key species - M. sibiricum and M. spicatum - among which probably even more aggressive hybrids were recently identified, have similar hexaploid level. Thus flow cytometry cannot facilitate...
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Martin, Grant D., and Julie Coetzee. "Competition between two aquatic macrophytes, Lagarosiphon major (Ridley) Moss (Hydrocharitaceae) and Myriophyllum spicatum Linnaeus (Haloragaceae) as influenced by substrate sediment and nutrients." 2014. http://hdl.handle.net/10962/76925.
Full textAbstract:
Competition between two globally economic and ecologically important submerged aquatic macrophytes, Lagarosiphon major (Rid.) Moss ex Wager and Myriophyllum spicatum L., was studied in response to growing in different substrate nutrient and sediment treatments. Addition series experiments were conducted with mixed plantings of L. major and M. spicatum grown under two soil nutrient concentrations (high vs. low) and two sediment treatments (sand vs. loam). Competitive ability of the plants was determined using an inverse linear model of the total dry weights as the yield variable. In high nutrient sediment treatments, L. major was the stronger competitor relative to M. spicatum, with one L. major plant being competitively equivalent to 2.5 M. spicatum plants in terms of their respective ability to reduce L. major biomass. In the loam sediment treatments, L. major was an even stronger competitor relative to M. spicatum with one L. major being equivalent to 10 M. spicatum plants. Additionally, L. major had a faster relative growth rate (RGR) than M. spicatum when grown in mixed cultures, a loam sediment type and at both high and low planting densities. The results indicated that L. major is a superior competitor to M. spicatum and that both nutrient and sediment conditions significantly affect the competitive ability of both species. The results contribute to the understanding of competition between submerged invasive macrophytes, and provide insight into the establishment and spread of invasive submerged macrophytes.
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Theriot, Edwin Anthony. "The molecular biology of cell surface interaction between submersed aquatic plants (Myriophyllum spicatum and Hydrilla verticillata) and components of their natural microflora." 1991. https://scholarworks.umass.edu/dissertations/AAI9120948.
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The submersed aquatic plants Eurasian watermilfoil (Myriophyllum spicatum) and Hydrilla (Hydrilla verticillata) are a nuisance in waterways of the U.S. Biological control with plant pathogens is a proven method for the management of aquatic plants. An attempt was made to identify lectins of Eurasian watermilfoil and Hydrilla tissues in hopes of characterizing a means of specific attachment to fungal pathogens on the target plants. Four fungal isolates (Fusarium roseum, Macrophomena phaseolina, Colletotrichum gloeosporioides and Mycoleptodiscus terrestris) were evaluated for the ability to attach and infect Eurasian watermilfoil and Hydrilla. Lectins were isolated from total protein by affinity chromatography. Lectin activity was evaluated for agglutination of the human ABO blood groups and fungal mycelium. Eurasian watermilfoil lectin was evaluated for its ability to inhibit fungal growth. No specific attachment was detected on Hydrilla tissues. F. roseum attached specifically to Eurasian watermilfoil tissues. All four fungi were pathogenic on Hydrilla tissues after seven days in test tube bioassays. All but F. roseum were pathogenic on Eurasian watermilfoil. Lectins specific for $\alpha$-L-fucose were isolated from both Eurasian watermilfoil and Hydrilla. The Eurasian lectin has a molecular weight of 48 Kd. The Hydrilla lectin is a complex of two proteins with molecular weights of 67 Kd and 50 Kd. Both Eurasian and Hydrilla lectins agglutinated type O red blood cells. Hydrilla lectin has no affect on mycelial suspensions of the four fungi, while Eurasian lectin agglutinated all fungi except M. phaseolina. The existence of lectins in the aquatic plants Hydrilla verticillata and Myriophyllum spicatum has been demonstrated. Plant lectins play a role in plant-pathogen association through attachment and/or recognition. Where attachment is specific and the lectin agglutinates the fungus, disease resistance occurs. This evidence supports the theory that recognition through plant lectins is a host defense mechanism.
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Bell, Michael Thomas. "Aquatic macrophyte and animal communities in a recently restored brackish marsh: possible influences of restoration design and the invasive plant species Myriophyllum spicatum." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9361.
Full textAbstract:
The numerous benefits that wetlands provide make them essential to ecosystem services and ecological functions. Historically, wetland losses have been caused by natural and anthropogenic changes. In Texas, nearly 50% of coastal wetland habitat has been lost since the 1930s and losses in the Lower Neches watershed have been some of the most extensive. Restoration is a way to mitigate these losses and can be accomplished in many ways. Each restoration design creates different aquatic habitats that can influence both submerged aquatic vegetation (SAV) and faunal communities. The restoration of the Lower Neches Wildlife Management Area (LNWMA) has created the conditions for the growth of the invasive submerged macrophyte, Myriophyllum spicatum (Eurasian watermilfoil) which may be competing with the native aquatic grass, Ruppia maritima (widgeongrass) for essential nutrients. In this study, an attempt was made to link restoration design with both SAV and aquatic fauna community structures by using a throw trap to characterize assemblages observed in three different types of restored marshes. We also performed two controlled mesocosm experiments in 0.5 gal aquariums to determine growth inhibition by M. spicatum on R. maritima. Analyses using Kruskal-Wallis non-parametric test determined that temporal variations in fauna and SAV community composition was greater than any restoration effect. Discriminant Function Analyses (DFAs) determined two to three key faunal species that best predicted association among restoration designs, but linear regressions could not determine any consistent relationship between individual species density and biomass of the dominant SAV species, M. spicatum. For the mesocosm experiments, M. spicatum inhibited the biomass production and branch count of R. maritima when the two species are grown together (ANOVA, p = 0.004 and 0.003, respectively). Changes in SAV assemblages due to competition and habitat characteristics could play a major role in determining faunal community.
In order to minimize the temporal effect observed and better determine any habitat pattern that may be present, a much longer study is necessary.
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KÁVOVÁ, Tereza. "Populačně genetické aspekty rostlinných invazí: studie genetické a cytotypové variability u invazních a nativních populací \kur{Phalaris arundinacea} L. a \kur{Myriophyllum} sp." Doctoral thesis, 2019. http://www.nusl.cz/ntk/nusl-395533.
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