Relevant bibliographies by topics / Zoospores

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Zoospores'

Author: Grafiati
Published: 4 June 2021
Last updated: 15 March 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Zoospores.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Zoospores"

1

Maier, Michelle A., Kimiko Uchii, Tawnya D. Peterson, and Maiko Kagami. "Evaluation of Daphnid Grazing on Microscopic Zoosporic Fungi by Using Comparative Threshold Cycle Quantitative PCR." Applied and Environmental Microbiology 82, no. 13 (April 22, 2016): 3868–74. http://dx.doi.org/10.1128/aem.00087-16.

Full text
Abstract:
ABSTRACTLethal parasitism of large phytoplankton by chytrids (microscopic zoosporic fungi) may play an important role in organic matter and nutrient cycling in aquatic environments by shunting carbon away from hosts and into much smaller zoospores, which are more readily consumed by zooplankton. This pathway provides a mechanism to more efficiently retain carbon within food webs and reduce export losses. However, challenges in accurate identification and quantification of chytrids have prevented a robust assessment of the relative importance of parasitism for carbon and energy flows within aquatic systems. The use of molecular techniques has greatly advanced our ability to detect small, nondescript microorganisms in aquatic environments in recent years, including chytrids. We used quantitative PCR (qPCR) to quantify the consumption of zoospores byDaphniain laboratory experiments using a culture-based comparative threshold cycle (CT) method. We successfully quantified the reduction of zoospores in water samples duringDaphniagrazing and confirmed the presence of chytrid DNA inside the daphnid gut. We demonstrate that comparativeCTqPCR is a robust and effective method to quantify zoospores and evaluate zoospore grazing by zooplankton and will aid in better understanding how chytrids contribute to organic matter cycling and trophic energy transfer within food webs.IMPORTANCEThe study of aquatic fungi is often complicated by the fact that they possess complex life cycles that include a variety of morphological forms. Studies that rely on morphological characteristics to quantify the abundances of all stages of the fungal life cycle face the challenge of correctly identifying and enumerating the nondescript zoospores. These zoospores, however, provide an important trophic link between large colonial phytoplankton and zooplankton: that is, once the carbon is liberated from phytoplankton into the parasitic zoospores, the latter are consumed by zooplankton and carbon is retained in the aquatic food web rather than exported from the system. This study provides a tool to quantify zoospores and evaluate the consumption of zoospores by zooplankton in order to further our understanding of their role in food web dynamics.
APA, Harvard, Vancouver, ISO, and other styles
2

Shipton, WA. "Regulation by Ions of Zoospore Release in Pythium." Australian Journal of Botany 35, no. 1 (1987): 79. http://dx.doi.org/10.1071/bt9870079.

Full text
Abstract:
In a Pythium species causing equine phycomycosis, release of zoospores from vesicles is regulated by K+ in the presence of either Ca2+ or Mg2+ . In the presence of K+ (16 mM ) , numerous vesicles were formed but, in most, mature zoospores failed to develop to maturity and both immature zoospores and vesicles disintegrated unless Ca,2+ (0.3�M -3mM ) or Mg2+ (0.3�M - 0.3mM) were present. The effect of K+ can be replaced partially by Rb+. Addition of Li+, Cs+ or NH4+ ions to colonies 4 h after zoospore induction had commenced led to vesicle lysis and to the formation of abnormal spores and bizarre-shaped bodies in vesicles; simultaneous addition of Ca2+ (3mM) exerted a particularly marked stabilising effect on vesicle structure. Zoospore motility both in the vesicle and after release was reduced or completely inhibited by K+ (16 mM) . Group I elements generally inhibited zoospore motility with the notable exception of Na+. Some group 11 elements inhibited zoospore motility but Ca2+ and Mg2+ were notable exceptions. Vesicle membranes induced in the presence of K+ and Ca2+ (16 and 3 mM respectively) were up to eight times thicker than membranes induced in distilled water. Zoospore motility, zoospore encystment and membrane stability appear to be critical factors in the release of zoospores from vesicles.
APA, Harvard, Vancouver, ISO, and other styles
3

Kong, Ping, and Chuanxue Hong. "Zoospore Density-Dependent Behaviors of Phytophthora nicotianae Are Autoregulated by Extracellular Products." Phytopathology® 100, no. 7 (July 2010): 632–37. http://dx.doi.org/10.1094/phyto-100-7-0632.

Full text
Abstract:
Phytophthora species are destructive fungus-like plant pathogens that use asexual single-celled flagellate zoospores for dispersal and plant infection. Many of the zoospore behaviors are density-dependent although the underlying mechanisms are poorly understood. Here, we use P. nicotianae as a model and demonstrate autoregulation of some zoospore behaviors using signal molecules that zoospores release into the environment. Specifically, zoospore aggregation, plant targeting, and infection required or were enhanced by threshold concentrations of these signal molecules. Below the threshold concentration, zoospores did not aggregate and move toward a cauline leaf of Arabidopsis thaliana (Col-0) and failed to individually attack annual vinca (Catharanthus roseus cv. Little Bright Eye). These processes were reversed when supplemented with zoospore-free fluid (ZFF) prepared from a zoospore suspension above threshold densities but not with calcium chloride at a concentration equivalent to extracellular Ca2+ in ZFF. These results suggest that Ca2+ is not a primary signal molecule regulating these communal behaviors. Zoospores coordinated their communal behaviors by releasing, detecting, and responding to signal molecules. This chemical communication mechanism raises the possibility that Phytophthora plant infection may not depend solely on zoospore number in the real world. Single zoospore infection may take place if it is signaled by a common molecule available in the environment which contributes to the destructiveness of these plant pathogens.
APA, Harvard, Vancouver, ISO, and other styles
4

von Broembsen, Sharon L., and J. W. Deacon. "Calcium Interference with Zoospore Biology and Infectivity of Phytophthora parasitica in Nutrient Irrigation Solutions." Phytopathology® 87, no. 5 (May 1997): 522–28. http://dx.doi.org/10.1094/phyto.1997.87.5.522.

Full text
Abstract:
Calcium, applied as either CaCl2 or Ca(NO3)2 to water or calcium-free soluble fertilizer solution (Peters 20-10-20 Peat Lite Special), affected several important stages of Phytophthora parasitica zoospore behavior relevant to infection and disease spread. Release of zoospores from sporangia was suppressed by Ca2+ concentrations in the range of 10 to 50 meq. These concentrations also curtailed zoospore motility; 20 meq of Ca2+ in fertilizer solution caused all zoospores to encyst within 4 h, whereas 94% of zoospores remained motile in unamended solution. In addition, Ca2+ in the range of 10 to 30 meq stimulated zoospore cysts to germinate in the absence of an organic nutrient trigger, while suppressing the release of a single zoospore (diplanetism) from cysts that did not germinate. In growth chamber experiments, the amendment of the fertilizer solution with 10 or 20 mM Ca(NO3)2 greatly suppressed infection of flood-irrigated, containerized vinca seedlings in a peat-based mix by motile or encysted zoospores of P. parasitica. These results demonstrate that Ca2+ amendments interfere with P. parasitica zoospore biology at multiple stages, with compounding effects on epidemiology, and suggest that manipulation of Ca2+ levels in irrigation water or fertilizer solutions could contribute to management of Phytophthora in recirculating irrigation systems.
APA, Harvard, Vancouver, ISO, and other styles
5

Liu, Fang, Bao-hua Li, Sen Lian, Xiang-li Dong, Cai-xia Wang, Zhen-fang Zhang, and Wen-xing Liang. "Effects of Temperature and Moisture on the Infection and Development of Apple Fruit Rot Caused by Phytophthora cactorum." Plant Disease 102, no. 9 (September 2018): 1811–19. http://dx.doi.org/10.1094/pdis-07-17-1028-re.

Full text
Abstract:
Phytophthora fruit rot, caused by Phytophthora cactorum, is an important disease of apple in China, often causing more than 50% fruit rot in rainy years. We examined the effects of temperature and moisture on the development of the disease and effects of the variables on zoospore release and germination, infection, and lesion development. In vitro, a temperature range of 5 to 20°C had no significant effects on zoospore release dynamics but did significantly affect the quantities of released zoospores. The largest quantity of zoospores was released at 9.9°C according to a fitted model. Zoosporangia released zoospores within 15 min at the test temperatures (0 to 20°C), which peaked at the fourth hour. Zoospores germinated in vitro, requiring free water, at temperatures from 5 to 35°C. The optimum germination temperature was 25.1°C according to a fitted model. The minimum wetness duration required for zoospores to complete the infection process and induce visible lesions on Fuji fruit was 0.40 h at the optimal temperature of 23.0°C according to the fitted model, whereas observed values were 4.5, 1.5, 0.5, 1.5 and 8.5 h at 10, 15, 20, 25, and 30°C, respectively. The number of zoospore infections on fruit at various temperatures and wetness durations were well fitted by the modified Weibull model; based on the model, the optimal temperature for zoospore infections was 23.0°C. Young apple fruit infected by zoospores developed visible lesions from 10 to 30°C, with a predicted optimum of 23.5°C; no lesions developed at 5 or 35°C. The shortest incubation period of the disease was 4 days. These results can be used to develop disease forecasting models for improved fungicide control.
APA, Harvard, Vancouver, ISO, and other styles
6

Kakani, Kishore, Marjorie Robbins, and D'Ann Rochon. "Evidence that Binding of Cucumber Necrosis Virus to Vector Zoospores Involves Recognition of Oligosaccharides." Journal of Virology 77, no. 7 (April 1, 2003): 3922–28. http://dx.doi.org/10.1128/jvi.77.7.3922-3928.2003.

Full text
Abstract:
ABSTRACT Despite the importance of vectors in natural dissemination of plant viruses, relatively little is known about the molecular features of viruses and vectors that permit their interaction in nature. Cucumber necrosis virus (CNV) is a small spherical virus whose transmission in nature is facilitated by zoospores of the fungus Olpidium bornovanus. Previous studies have shown that specific regions of the CNV capsid are involved in transmission and that transmission defects in several CNV transmission mutants are due to inefficient attachment of virions to the zoospore surface. In this study, we have undertaken to determine if zoospores contain specific receptors for CNV. We show that in vitro binding of CNV to zoospores is saturable and that vector zoospores bind CNV more efficiently than nonvector zoospores. Further studies show that treatment of zoospores with periodate and trypsin reduces CNV binding, suggesting the involvement of glycoproteins in zoospore attachment. In virus overlay assays, CNV binds to several proteins, whereas CNV transmission mutants either fail to bind or bind at significantly reduced levels. The possible involvement of specific sugars in attachment was investigated by incubating CNV with zoospores in the presence of various sugars. Two mannose derivatives (methyl α-d-mannopyranoside and d-mannosamine), as well as three mannose-containing oligosaccharides (mannotriose, α3,α6-mannopentaose, and yeast mannan) and l-(−)-fucose, all inhibited CNV binding at relatively low concentrations. Taken together, our studies suggest that binding of CNV to zoospores is mediated by specific mannose and/or fucose-containing oligosaccharides. This is the first time sugars have been implicated in transmission of a plant virus.
APA, Harvard, Vancouver, ISO, and other styles
7

Erb, W. A., J. N. Moore, and R. E. Sterne. "Attraction of Phytophthora cinnamomi Zoospores to Blueberry Roots." HortScience 21, no. 6 (December 1986): 1361–63. http://dx.doi.org/10.21273/hortsci.21.6.1361.

Full text
Abstract:
Abstract The attraction of zoospores of Phytophthora cinnamomi Rands to roots of three cultivars of rabbiteye blueberry (Vaccinium ashei Reade), two species hybrid cultivars of highbush blueberry, and one tetraploid species hybrid selection (US 109) was compared. Zoospores were attracted to the roots of all plants tested. Roots of highbush cultivars ‘Bluetta’ and ‘Patriot’ attracted more zoospores than the rabbiteye cultivars. The number of zoospores attracted to roots of US 109 was greater than the number attracted to the three rabbiteye cultivars, but less than the highbush cultivars. Increased zoospore attraction appeared to be related to root rot susceptibility in blueberries.
APA, Harvard, Vancouver, ISO, and other styles
8

Kasteel, Michiel, Tharun P. Rajamuthu, Joris Sprakel, Tijs Ketelaar, and Francine Govers. "Phytophthora zoospores display klinokinetic behaviour in response to a chemoattractant." PLOS Pathogens 20, no. 9 (September 30, 2024): e1012577. http://dx.doi.org/10.1371/journal.ppat.1012577.

Full text
Abstract:
Microswimmers are single-celled bodies powered by flagella. Typical examples are zoospores, dispersal agents of oomycete plant pathogens that are used to track down hosts and infect. Being motile, zoospores presumably identify infection sites using chemical cues such as sugars, alcohols and amino acids. With high-speed cameras we traced swimming trajectories of Phytophthora zoospores over time and quantified key trajectory parameters to investigate chemotactic responses. Zoospores adapt their native run-and-tumble swimming patterns in response to the amino acid glutamic acid by increasing the rate at which they turn. Simulations predict that tuneable tumble frequencies are sufficient to explain zoospore aggregation, implying positive klinokinesis. Zoospores thus exploit a retention strategy to remain at the plant surface once arriving there. Interference of G-protein mediated signalling affects swimming behaviour. Zoospores of a Phytophthora infestans G⍺-deficient mutant show higher tumbling frequencies but still respond and adapt to glutamic acid, suggesting chemoreception to be intact.
APA, Harvard, Vancouver, ISO, and other styles
9

Pozdnyakov, Igor R., Alexei O. Seliuk, Kristina O. Barzasekova, and Sergey A. Karpov. "Gene Expression in Aphelid Zoospores Reveals Their Transcriptional and Translational Activity and Alacrity for Invasion." Journal of Fungi 11, no. 1 (January 16, 2025): 68. https://doi.org/10.3390/jof11010068.

Full text
Abstract:
In Aphelidium insulamus (Opisthokonta, Aphelida) zoospores, the expression of 7708 genes out of 7802 described genes was detected. For 589 of them, expression levels were shown to be more than 10 times higher than the median level. Among the highly expressed genes with known functions, the largest functional categories were “Cellular Metabolism”, “Protein Synthesis”, “Cell State Control”, and “Nucleic Acid Processing”. Unlike fungal zoospores, translational and transcriptional activity was demonstrated for A. insulamus zoospores. With increasing temperature, the expression of many zoospore genes changed dramatically; the expression of heat shock and chaperone protein genes multiplied more than 30 times, indicating the high sensitivity of aphelid zoospores and their response to environmental changes.
APA, Harvard, Vancouver, ISO, and other styles
10

Kerwin, James L., Lisa M. Johnson, Howard C. Whisler, and Amy R. Tuininga. "Infection and morphogenesis of Pythium marinum in species of Porphyra and other red algae." Canadian Journal of Botany 70, no. 5 (May 1, 1992): 1017–24. http://dx.doi.org/10.1139/b92-126.

Full text
Abstract:
A strain of Pythium marinum (Peronosporales: Pythiaceae) from Puget Sound, Washington, was isolated from lesions of Porphyra nereocystis. The fungus grew on a modified Vishniac medium, from temperatures of 4 to 25 °C, although growth was slow at the lowest temperature. Sexual and asexual reproduction also occurred within this temperature range. Mycelium diluted in seawater initiated zoospore release within 16 h and continued to release zoospores for over 200 h at temperatures from 4 to 20 °C. Zoospore encystment on several species of marine red, brown, and green algae was readily monitored following staining with lactophenol – cotton blue. Pythium marinum zoospore encystment occurred on rhodophyceaen species, including Porphyra (gametophytes), Gigartina exasperata (tetrasporophyte), Mastocarpus papillatus (gametophyte), Prionitis lanceolata (nonfertile), and Iridaea heterocarpa (gametophyte and tetrasporophyte), but not on Nereocystis leutkeana or Ulva lactuca. Over 50% of zoospores held in half-strength seawater at 4 and 20 °C encysted within 24 h, whereas those held at 12 °C reached 50% encystment only after 32 h. For 4-mm diameter discs of Porphyra nereocystis and Porphyra perforata (formerly Porphyra sanjuanensis) blades, there was only a transient relationship between cell damage and number of encysted zoospores. Zoospores did not attach to the conchocelis phase of two species of Porphyra. Sequential extraction of carbohydrates from the blades of Porphyra perforata implicated separate chemical signals for zoospore encystment and appressorium formation prior to the initiation of blade invasion. Addition of diverse monosaccharides and polysaccharides to zoospore suspensions suggested that these chemical signals are specific, with the attachment–encystment signal chemically related to polysaccharides consisting of sulfated or nonsulfated galactose and 3,6-anhydrogalactose found in commercial agars and carrageenans. There was no consistent relationship between zoospore encystment and the amount of 3,6-anhydrogalactose present in the blade phase of several species of red algae. Key words: Pythium, Porphyra, zoospore, encystment, sulfated galactans, 3,6-anhydrogalactose.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Zoospores"

1

Savory, Andrew. "Swimming patterns of zoospores." Thesis, University of Dundee, 2013. https://discovery.dundee.ac.uk/en/studentTheses/417e5e5d-bb27-4fc3-af1f-c96faae0faa6.

Full text
Abstract:
Phytophthora infestans is a highly destructive plant pathogen and the causal agent of the potato blight disease that devastated Ireland’s potato crops in the 19th century.Today, this disease is still a serious problem, with global crop losses and spending oncontrol measures estimated to exceed £3 billion annually. A key to the success of P. infestans is the dispersal of free-swimming zoospore cells from infected plant tissue into aqueous environments. These cells are specialised infection agents that have evolved an array of tactic responses in order to locate and infect new hosts. An interesting and poorly understood aspect of zoospore behaviour is the phenomenon of auto-aggregation. That is, large numbers of zoospores observed in vitro are seen to form complex, large-scale patterns in the absence of external signals or stimuli. Current competing hypotheses suggest that patterns are formed by one of two distinct, concentrative phenomena: chemotaxis and bioconvection. In this thesis we investigate the mechanics and implications of zoospore auto-aggregation behaviour using an interdisciplinary approach that combines continuum mathematical modelling with laboratory experimental work. We investigate the modelling of chemotactic and bioconvective processes and compare results with our experimental observations. Finally, we present a novel bioconvection-chemotaxis model and thus provide strong evidence to support the hypothesis that auto-aggregation in P. infestans zoospores results from a necessary combination of these processes.
APA, Harvard, Vancouver, ISO, and other styles
2

Donaldson, Stephen P. "The behaviour of zoospores of Pythium species." Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/13681.

Full text
Abstract:
Pythium aphanidermatum (Edson) Fitz., Pythium catenulatum Matthews and Pythium dissotocum Drechs. were compared for responses to amino acids and sugars in tests involving taxis, zoospore encystment and cyst germination in vitro. Comparisons were made between the fungi and for each fungus at these three stages of development, which are parts of the normal sequence leading to infection of host roots or colonisation of non-living substrata from zoospores. Other substances tested for induction of encystment or germination in vitro were cellulose film, crab shell, uronic acids or uronate-containing compounds, partially characterised polysaccharides from plants, root mucilages and cations. Motility attributes of the fungi were compared and, for P. aphanidermatum only, were characterised in the presence of several ions and compounds that interfere with calcium-mediated events (EGTA, dibucaine, trifluoperazine, lanthanum, verapamil, amiloride, A3187 and TMB-8). Amino acids were tested for competitive effects in chemotaxis assays in vitro. Calcium and EGTA were also tested for effects on adhesion of encysted spores to glass slides. Accumulation and encystment of P. aphanidermatum on detached wheat roots was studied on microscope slides, with or without prior treatment of roots with calcium alginate gel, methylene blue, alcian blue, India, ink ruthenium red and lectins that bind residues of fucose, D-glucose, D-mannose, N-acetyl-D-glucosamine and N-acetyl-D-galactosamine. Many experiments involved video-recording zoospore responses and subsequent analysis of videotapes. Evidence is presented for an effect of calcium and other divalent cations on zoospore motility patterns, cyst adhesion and induction of germination. Several amino acids and sugars elicited zoospore taxis, encystment, or cyst germination but sometimes differently for different fungi or at these different stages of development. Competition experiments enabled some of these responses to be related to proposed receptor functions, and in some cases amino acids could overcome inhibition of germination caused by the presence of calcium-modulators.
APA, Harvard, Vancouver, ISO, and other styles
3

McGinley, Susan. "Exploding Zoospores: Using Biosurfactants to Control Plant Pathogens." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/622309.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Osborne, Meave Catherine. "The spatial ecology of phytopathogenic zoospores in the rhizosphere." Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369560.

Full text
Abstract:
This thesis is concerned with an analysis of swimming of oomycete zoospores, particularly in relation to the hypothesis that electrotaxis mediated host root colonisation. A correlation was found between the electrotactic behaviour of zoospores of Phytophthora palmivora and Pythium aphanidermatum and their localisation relative to anodic or cathodic regions of the majority of non-host roots. Cathodotropic P. aphanidermatum zoospores were found to be attracted to the cathode generated at the wound site on monocotyledonous and dicotyledonous plant roots studied. Zoospores of P. aphanidermatum were also found to become gradually less attracted to these wound sites as they dissipated over time. Anodotropic P. palmivora zoospores were found to be repelled by the cathodic wound sites on roots of all plants investigated, with the exception of Petunia hybrida. In addition to this zoospores of P. aphanidermatum were found not exhibit chemotaxis or encystment in gradients of the wound-specific metabolite acetosyringone. This suggests that electrotaxis and chemotaxis both operate in directing zoospore accumulation around roots. This reduction of the conductivity of the bathing medium by the addition of different concentrations of sodium chloride salts did not appear to affect the accumulation of both zoospore species around roots of rye grass. The results of this study supports the hypothesis that zoospores use electrotaxis as one means to locate new plant hosts in the rhizosphere. However, chemotaxis may still augment the regulation of zoospore colonisation and encystment.
APA, Harvard, Vancouver, ISO, and other styles
5

Jennings, Alice Ruth. "Cues for settlement of zoospores of the green alga, Enteromorpha." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273555.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Jones, Sion Wyn. "Responses of zoospores of Pythium aphanidermatum to attractants and toxins." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/15127.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Quaempts, Rex Matthew 1962. "Duration of zoospore motility of pythium species in situ." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276625.

Full text
Abstract:
Motile zoospores of P. dissotocum and P. catenulatum were added to 20 and 60 mesh silica sand and a sandy loam soil to investigate the duration of motility. Both Pythium species remained motile for up to 24 hours in all soil textures tested. However, the duration and percentage of the motile population varied depending upon the soil type and species tested. The duration of survival of motile and encysted zoospores of P. dissotocum and P. catenulatum in air dried and saturated sterile silica sand was also tested. P. dissotocum, under air dried conditions, did not survive while P. catenulatum was capable of surviving 4 and 16 days as motile and encysted zoospores, respectively. Both fungi could be recovered at high percentages after 5 weeks under saturated conditions. The survival structure is believed to be in the form of a zoospore cyst.
APA, Harvard, Vancouver, ISO, and other styles
8

Lupatelli, Carlotta Aurora. "Approche intégrative en protéomique et biophysique pour élucider la perception du signal et la motilité des zoospores de Phytophthora lors des premières étapes de l'interaction avec les plantes." Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ6037.

Full text
Abstract:
La propagation des maladies des plantes causées par Phytophthora repose notamment sur la dispersion dans le sol de zoospores unicellulaires, polarisées et biflagellées. Le mouvement des zoospores vers un hôte s'appuie sur divers mécanismes tels que la chimiotaxie, l'électrotaxie, la géotaxie négative et la rhéotaxie. Les signaux provenant des particules du sol et de la plante déterminent ce mouvement dirigé lors des premières étapes de la colonisation racinaire. Cependant, les mécanismes de perception du signal par les zoospores, qui conduisent au mouvement dirigé vers l'hôte, restent mal compris. Des questions cruciales subsistent concernant la nature et la spécificité de ces mécanismes par rapport à ceux utilisés par d'autres microorganismes du sol, ainsi que l'influence des caractéristiques dynamiques et morphologiques des zoospores sur leur mouvement guidé.Dans ce contexte, la première partie de ce travail a exploré les capacités de détection des zoospores de Phytophthora parasitica en analysant le répertoire protéique de leur membrane plasmique à l'aide d'une approche protéomique et de la LC-MS/MS. Les protéines d'échantillons membranaires ont été identifiées sur la base du protéome de référence de Phytophthora parasitica, permettant l'identification du répertoire membranaire et une comparaison des profils des fractions issues de corps cellulaires et flagellaires. Trois protéines membranaires clés associées aux mécanismes de détection et de réponse au mouvement des zoospores ont été plus particulièrement étudiées, dont certaines étaient spécifiquement localisées à la membrane flagellaire - une protéine de détection des stérols, une nucléotide cyclase et une Na+/K+ ATPase - supportant l'hypothèse d'un rôle critique des flagelles dans les mécanismes de perception du signal. Pour initier une analyse fonctionnelle de la détection des zoospores, des essais d'immunolocalisation, pharmacologiques et électrophysiologiques ont été initiés.La deuxième partie de cette thèse était basée sur une approche d'imagerie automatisée, pour développer une méthode de quantification de diverses caractéristiques de micronageurs du sol, y compris les zoospores, évoluant en une suspension microbienne et en réponse à un facteur sol/hôte (gradient de potassium). Dans ces conditions, les réponses de mouvement des zoospores ont été caractérisées, et comparées à celles d'autres espèces, montrant qu'il est possible de distinguer les morphologies, les trajectoires, les vitesses, et l'impact du facteur du sol dans une communauté synthétique simple composée de P. parasitica, Vorticella microstoma et Enterobacter aerogenes. Par ailleurs, une analyse biomécanique a été réalisée détaillant des métriques de mouvement des zoospores, telles que la vitesse, la géométrie des trajectoires et les fréquences de battement flagellaire sous le même stimulus, révélant des dynamiques de mouvement spécifiques aux zoospores par rapport à d'autres micronageurs. Ainsi, nous avons constaté que l'augmentation des concentrations de potassium perturbe le schéma de nage des zoospores, généralement caractérisé par des trajectoires longues et rectilignes alternant avec des culbutes périodiques. Les zoospores présentaient alors des trajectoires de plus en plus courtes et circulaires, avec une réduction de la vitesse et une altération du battement des flagelles.Ces résultats combinent des principes biochimiques et biomécaniques pour mieux comprendre les processus fondamentaux qui guident les espèces microbiennes vers des stimuli externes. Ce travail clarifie l'étendue des mécanismes de détection et des réponses de mouvement des zoospores de Phytophthora, améliorant notre compréhension de la phase de pré-colonisation et de la façon dont ces pathogènes se dirigent vers leurs plantes hôtes. Cette approche intégrée fournit des perspectives de compréhension des premiers stades de l'infection, par ailleurs utiles pour développer de nouvelles stratégies de gestion des maladies
The epidemic spread of plant diseases caused by Phytophthora is primarily based on the dispersal of unicellular, biflagellated zoospores in the soil. Zoospore guidance towards host plants relies on diverse mechanisms such as chemotaxis, electrotaxis, negative geotaxis and rheotaxis. Signals from soil particles and host plants critically influence these motion processes, guiding zoospores during the initial stages of root colonization. However, the mechanisms underlying zoospores perception, resulting in the directed motion toward hosts remain unclear. Critical questions include the nature and the specificity of these sensing mechanisms compared to those used by other soil microorganisms, and the extent to which the dynamic and morphological characteristics of zoospores contribute to their guided motion.In this context, the first part of this thesis focused on investigating the sensing capabilities of Phytophthora parasitica zoospores by analyzing their plasma membrane protein repertoire through a proteomic approach. Peptides were detected from membrane samples using LC-MS/MS, and related proteins were identified by mapping against the Phytophthora parasitica reference proteome, allowing for detailed characterization and comparison of the membrane profiles of the zoospore cell body and flagella fractions. Given the naturally polarized structure of zoospores, which exhibit two morphologically distinct flagella responsible for oriented motion, we hypothesized a critical role of flagella in sensing mechanisms. Our analysis identified three prominent membrane proteins associated with sensing and motion response mechanisms in zoospores, some of which were specifically localized to the flagella membrane: a sterol-sensing protein, a nucleotide cyclase and a Na+/K+ ATPase. To start a functional analysis in zoospore sensing, immunolocalization, pharmacological and electrophysiological assays were initiated.The second part of this thesis employed an automated high-content imaging approach to establish a novel method for quantifying diverse characteristics of soil microswimmers, including zoospores, in response to a soil/host factor (potassium gradient). The initial observations focused on the motion responses of zoospores among other species, demonstrating the feasibility to simultaneously distinguish morphologies, trajectories, velocities, and the impacts of the soil factor on a simple synthetic microbial community composed of P. parasitica, Vorticella microstoma, and Enterobacter aerogenes. Following these observations, a detailed biomechanical analysis was conducted to quantify motion metrics, such as velocity, trajectory geometry, and flagellar beating patterns under the same stimulus, revealing specific motion dynamics unique to zoospores compared to other microswimmers. As a result, we found that increasing potassium concentrations disrupt the normal swimming pattern of zoospores, typically characterized by long, straight runs and periodic tumbles. Instead, the zoospores exhibited progressively shorter and more circular trajectories, with reduced velocity and altered flagella beatingThese findings integrate biochemical and biomechanical principles to advance the understanding of the fundamental biological process of microbial guidance toward external cues. Elucidating the sensing mechanisms and motion responses of Phytophthora zoospores enhances our understanding of the pre-colonization phase of plant infection, highlighting how these pathogens move toward hosts. This integrated approach offers valuable insights into early infection stages, potentially guiding new plant disease management strategies
APA, Harvard, Vancouver, ISO, and other styles
9

Piotrowski, Jeffery Scott. "Physiology, Enzyme Production, and Zoospore Behavior of Balrachochytrium dendrobatidis, a Chytrid Pathogenic to Amphibians." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/PiotrowskiJS2002.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Riggs, Kara. "Chemotaxis of Phytophthora sojae zoospores to soybean roots is altered by isoflavone silencing." Connect to resource, 2010. http://hdl.handle.net/1811/45485.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Zoospores"

1

institut, Murmanskiĭ morskoĭ biologicheskiĭ, ed. Povedenie zoospor Laminaria saccharina (Phaeophyta). Apatity: Kolʹskiĭ nauch. t͡sentr RAN, 1992.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Jennings, Alice Ruth. Cues for settlement of zoospores of the green alga, Enteromorpha. Birmingham: University of Birmingham, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Patel, Pratixa. Interaction between marine biofilms and the zoospores of the green macrofouling alga Enteromorpha. Birmingham: University of Birmingham, 2003.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Estrada-Garcia, Maria Teresa. Analysis of cell surface components of zoospores and cysts of Pythium aphanidermatum (Edson) Fitz.with monoclonal antibodies. Birmingham: University of Birmingham, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

service), SpringerLink (Online, ed. How Do Spores Select Where to Settle?: A Holographic Motility Analysis of Ulva Zoospores on Different Surfaces. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2011.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

1956-, Usha Kiran, ed. Zoosporic fungi of India. New Delhi, India: Inter-India Publications, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

North Carolina Sea Grant College Program., ed. Research on toxic algae: Pfiesteria-like organisms : occupational risks of crabbing, neurobehavioral effects of exposure in rats, consumer health risks of exposed seafood, effects of nutrients on zoospore stage. [Raleigh, N.C.]: Sea Grant North Carolina, 1998.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Sadowski, Laura A. Cytochemical localization of carbohydrates in zoospores of Aphanomyces euteiches. 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Roychoudhury, Sonali. Analysis of ultrastructural characters of zoospores and the mitotic apparatus in systematics of Chytridiomycetes / by Sonali Roychoudhury. 1989.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Randolph, Logan Ray. Production and fine structure of the secondary zoospores of apodachlya pyrifera zopf. 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Zoospores"

1

Heydt, Matthias. "Results: Motility and Exploration Behavior of Ulva Zoospores." In How Do Spores Select Where to Settle?, 51–83. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-17217-5_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Huitema, Edgar, Matthew Smoker, and Sophien Kamoun. "A Straightforward Protocol for Electro-transformation of Phytophthora capsici Zoospores." In Methods in Molecular Biology, 129–35. Totowa, NJ: Humana Press, 2011. http://dx.doi.org/10.1007/978-1-61737-998-7_11.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Heydt, Matthias. "Discussion of the Motility of Ulva Zoospores in Vicinity to Surfaces." In How Do Spores Select Where to Settle?, 85–109. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-17217-5_6.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Tahara, Satoshi, and Tofazzal Islam. "Secondary Metabolites with Diverse Activities toward Phytopathogenic Zoospores ofAphanomyces cochlioidesin Host and Nonhost Plants." In ACS Symposium Series, 202–15. Washington, DC: American Chemical Society, 2004. http://dx.doi.org/10.1021/bk-2005-0892.ch019.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Santos, Lilia M. A., and G. F. Leedale. "Vischeria stellata (Eustigmatophyceae): ultrastructure of the zoospores, with special reference to the flagellar apparatus." In The Cytoskeleton of Flagellate and Ciliate Protists, 160–67. Vienna: Springer Vienna, 1991. http://dx.doi.org/10.1007/978-3-7091-6714-4_13.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Gubler, Frank, and Adrienne R. Hardham. "The Fate of Peripheral Vesicles in Zoospores of Phytophthora cinnamomi During Infection of Plants." In Electron Microscopy of Plant Pathogens, 197–210. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-75818-8_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Gilbert, G. S., J. Handelsman, and J. L. Parke. "Role of ammonia and calcium in lysis of zoospores of Phytophthora spp. by Bacillus cereus strain UW85." In The Rhizosphere and Plant Growth, 300. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3336-4_58.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Islam, Md Tofazzal, Toshiaki Ito, and Satoshi Tahara. "Host-specific plant signal and G-protein activator, mastoparan, trigger differentiation of zoospores of the phytopathogenic oomycete Aphanomyces cochlioides." In Roots: The Dynamic Interface between Plants and the Earth, 131–42. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-2923-9_13.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Stouvenakers, Gilles, Peter Dapprich, Sebastien Massart, and M. Haïssam Jijakli. "Plant Pathogens and Control Strategies in Aquaponics." In Aquaponics Food Production Systems, 353–78. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-15943-6_14.

Full text
Abstract:
AbstractAmong the diversity of plant diseases occurring in aquaponics, soil-borne pathogens, such as Fusarium spp., Phytophthora spp. and Pythium spp., are the most problematic due to their preference for humid/aquatic environment conditions. Phytophthora spp. and Pythium spp. which belong to the Oomycetes pseudo-fungi require special attention because of their mobile form of dispersion, the so-called zoospores that can move freely and actively in liquid water. In coupled aquaponics, curative methods are still limited because of the possible toxicity of pesticides and chemical agents for fish and beneficial bacteria (e.g. nitrifying bacteria of the biofilter). Furthermore, the development of biocontrol agents for aquaponic use is still at its beginning. Consequently, ways to control the initial infection and the progression of a disease are mainly based on preventive actions and water physical treatments. However, suppressive action (suppression) could happen in aquaponic environment considering recent papers and the suppressive activity already highlighted in hydroponics. In addition, aquaponic water contains organic matter that could promote establishment and growth of heterotrophic bacteria in the system or even improve plant growth and viability directly. With regards to organic hydroponics (i.e. use of organic fertilisation and organic plant media), these bacteria could act as antagonist agents or as plant defence elicitors to protect plants from diseases. In the future, research on the disease suppressive ability of the aquaponic biotope must be increased, as well as isolation, characterisation and formulation of microbial plant pathogen antagonists. Finally, a good knowledge in the rapid identification of pathogens, combined with control methods and diseases monitoring, as recommended in integrated plant pest management, is the key to an efficient control of plant diseases in aquaponics.
APA, Harvard, Vancouver, ISO, and other styles
10

Sime-Ngando, Télesphore, Marlène Jobard, and Serena Rasconi. "Fluorescence In Situ Hybridization of Uncultured Zoosporic Fungi." In Laboratory Protocols in Fungal Biology, 231–36. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-2356-0_18.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Zoospores"

1

Sarkar, Debolina, Yiling Sun, Ayelen Tayagui, Ryan Adams, Ashley Garrill, and Volker Nock. "Microfluidic Platform to Study Electric Field Based Root Targeting by Pathogenic Zoospores." In 2022 IEEE 35th International Conference on Micro Electro Mechanical Systems Conference (MEMS). IEEE, 2022. http://dx.doi.org/10.1109/mems51670.2022.9699559.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Пырсиков, А. С., К. Д. Чайчук, and Н. А. Милюкова. "ANALYSIS OF BREEDING SAMPLES OF TOMATO (Solanum lycopersucum) AND IDENTIFICATION OF THEIR ALLELES OF THE Ph-3 GENE OF RESISTANCE TO PHYTOPHTHOROSIS." In Биотехнология в растениеводстве, животноводстве и сельскохозяйственной микробиологии, 47–48. Crossref, 2021. http://dx.doi.org/10.48397/arriab.2021.21.xxi.023.

Full text
Abstract:
Фитофтороз (или бурая гниль) – крайне вредоносная инфекция, распространенная среди семейства паслёновых, особенно для таких важных сельскохозяйственных культур как картофель и томат. Возбудителем является гриб отдела оомицеты Рhytophthora infestans (Мont.) de Вary. Проявляется заболевание в виде удлиненных темно-коричневых пятен или полос на стеблях и черешках растений, серовато-бурых – на листьях, коричнево-бурых – на плодах. Пораженные плоды теряют товарные качества, становятся непригодными к дальнейшим циклам реализации (переработка, транспортировка, хранение). Начинаясь с нижних ярусов листьев, патоген постепенно захватывает весь куст томата. Благоприятные условия для заражения – температура ниже 15 градусов и высокая влажность, после чего конидии прорастают в зооспоры, причем каждая способна образовывать до 16 зооспор [1]. Late blight (or brown rot) is an extremely harmful infection common among the nightshade family, especially for such important crops as potatoes and tomatoes. The causative agent is the fungus of the oomycete department Phytophthora infestans (Mont.) de Bary. The disease manifests itself in the form of elongated dark brown spots or stripes on the stems and petioles of plants, grayish-brown on leaves, brown-brown on fruits. Affected fruits lose their commercial qualities, become unsuitable for further sales cycles (processing, transportation, storage). Starting from the lower tiers of leaves, the pathogen gradually captures the entire tomato bush. Favorable conditions for infection are temperatures below 15 degrees and high humidity, after which the conidia germinate into zoospores, each capable of forming up to 16 zoospores [1].
APA, Harvard, Vancouver, ISO, and other styles
3

Сидоров, Л. А., Н. А. Милюкова, and А. С. Пырсиков. "ANALYSIS OF THE SUNFLOWER COLLECTION FOR THE Pl6 LOCUS RESPONSIBLE FOR THE RESISTANCE OF HELIANTHUS ANNUUS TO DOWY POWDERY DEW." In Биотехнология в растениеводстве, животноводстве и сельскохозяйственной микробиологии, 53–54. Crossref, 2021. http://dx.doi.org/10.48397/arriab.2021.21.xxi.027.

Full text
Abstract:
Ложная мучнистая роса подсолнечника (ЛМР) - это заболевание растения, которое вызывается возбудителем Plasmopara halstedii (Farl.) из порядка Peronosporales, который принадлежит к оомицетам. Является облигатным паразитом, образует в органах растения толстую ветвящуюся границу диаметром 6-9 мкм с зернистым бесцеветным или желтоватым содержимым. Источниками первичной инфекции являются ооспоры, которые сохраняются в почве до 10 лет; источником вторичной инфекции являются зооспоры. Проявляется одновременно, как и системно, так и локально. Симптомами заболевания являются белый налёт на нижней стороне листа, отсутствие гелиотропизма, замедленный рост, укороченные междоузлия, карликовость. Sunflower downy mildew (SMF) is a plant disease caused by the pathogen Plasmopara halstedii (Farl.) from the order Peronosporales, which belongs to the oomycetes. It is an obligate parasite that forms a thick branching border 6-9 µm in diameter with granular, colorless or yellowish contents in plant organs. Sources of primary infection are oospores that persist in the soil for up to 10 years; zoospores are the source of secondary infection. It manifests itself both systemically and locally. Symptoms of the disease are white bloom on the underside of the leaf, lack of heliotropism, slow growth, shortened internodes, dwarfism.
APA, Harvard, Vancouver, ISO, and other styles
4

Urzay, Javier, Donald Ott, and Manu Prakash. "Video: Spin of a giant multinucleated multiflagellate zoospore." In 67th Annual Meeting of the APS Division of Fluid Dynamics. American Physical Society, 2014. http://dx.doi.org/10.1103/aps.dfd.2014.gfm.v0053.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Sun, Yiling, Ayelen Tayagui, Ashley Garrill, and Volker Nock. "A Monolithic Polydimethylsiloxane Platform for Zoospore Capture, Germination and Single Hypha Force Sensing." In 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII). IEEE, 2019. http://dx.doi.org/10.1109/transducers.2019.8808505.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Zoospores"

1

Katan, Jaacov, and Michael E. Stanghellini. Clinical (Major) and Subclinical (Minor) Root-Infecting Pathogens in Plant Growth Substrates, and Integrated Strategies for their Control. United States Department of Agriculture, October 1993. http://dx.doi.org/10.32747/1993.7568089.bard.

Full text
Abstract:
In intensive agriculture, harmful soilborne biotic agents, cause severe damage. These include both typical soilborne (clinical) major pathogens which destroy plants (e.g. Fusarium and Phytophthora pathogens), and subclinical ("minor") pathogens (e.g. Olpidium and Pythium). The latter cause growth retardation and yield decline. The objectives of this study were: (1) To study the behavior of clinical (major) and subclinical (minor) pathogens in plant growth substrate, with emphasis on zoosporic fungi, such as Pythium, Olipidium and Polymyxa. (2) To study the interaction between subclinical pathogens and plants, and those aspects of Pythium biology which are relevant to these systems. (3) To adopt a holistic-integrated approach for control that includes both eradicative and protective measures, based on a knowledge of the pathogens' biology. Zoospores were demonstrated as the primary, if not the sole propagule, responsible for pathogen spread in a recirculating hydroponic cultural system, as verified with P. aphanidermatum and Phytophthora capsici. P. aphanidermatum, in contrast to Phytophthora capsici, can also spread by hyphae from plant-to-plant. Synthetic surfactants, when added to the recirculating nutrient solutions provided 100% control of root rot of peppers by these fungi without any detrimental effects on plant growth or yield. A bacterium which produced a biosurfactant was proved as efficacious as synthetic surfactants in the control of zoosporic plant pathogens in the recirculating hydroponic cultural system. The biosurfactant was identified as a rhamnolipid. Olpidium and Polymyxa are widespread and were determined as subclinical pathogens since they cause growth retardation but no plant mortality. Pythium can induce both phenomena and is an occasional subclinical pathogen. Physiological and ultrastructural studies of the interaction between Olpidium and melon plants showed that this pathogen is not destructive but affects root hairs, respiration and plant nutrition. The infected roots constitute an amplified sink competing with the shoots and eventually leading to growth retardation. Space solarization, by solar heating of the greenhouse, is effective in the sanitation of the greenhouse from residual inoculum and should be used as a component in disease management, along with other strategies.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Zoospores' for particular source types:
Journal articles Dissertations / Theses
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography