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Ducellieria chodatii. General view of 'Coelastrum stages' between the pollen grains in the collected sample.
Source publication
2013) First record of the parasitic aquatic oomycete Ducellieria chodatii from Pirin Mts (Bulgaria) with notes on its taxonomy, life cycle and ecology. – Sydowia 65 (1): 1–12. The present paper provides data on the new record of the interesting organism, transferred from algae to oomycotic stramenopilous fungi, Ducellieria chodatii, from southeaste...
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Figure S1 depicts phylogenetic trees of fungal sequences, rooted with an oomycete (heterokont) outgroup. Figure S1a shows phylogenetic trees based on independent and combined analyses of ribosomal RNA and RPB2 gene loci, which reflect the organismal phylogeny. Figure S1b presents phylogenetic trees based on independent and combined analyses of gene...
Citations
... Although not true fungi, they possess fungus-like hyphae, reproduce 2 S. Mcloughlin et al. both sexually and asexually, have saprotrophic or parasitic habits, and include forms that are pathogens on many fish, amphibians and crop plants. Like chytrids, some oomycetes are known to target dispersed pollen and are able to penetrate the robust sporopollenin wall (Stoyneva et al. 2013). Both chytrids and oomycetes are candidates for producing the spherical biotic structures found within Permian pollen grains from Antarctica. ...
... The dark spherical bodies found inside glossopterid pollen are preserved within the corpus (or more rarely the sacci) and may, plausibly, represent oomycete holocarpic thalli or oospores similar to those of the extant endobiotic parasite Ducellieria chodatii (F. Ducell.), which are known to occur in clusters within modern Pinaceae pollen (Hesse et al. 1989;Stoyneva et al. 2013; see also figure 1A of Buaya & Thines 2023). In typical Ducellieria, a zoospore bearing two laterally inserted flagella settles on a pollen grain, penetrates the wall layers and develops as an internal spherical to ovoid holocarpic thallus/zoosporangium. ...
... It is not uncommon for multiple zoospores to infest a single pollen grain. After many cycles, and where several zoospores penetrate a pollen grain, sexual reproduction may occur, and an oosporangium with a single, smooth, thickwalled resting spore (oospore) is developed (Hesse et al. 1989;Stoyneva et al. 2013). Indeed, a new order of obligate endobiotic pollen-parasitic oomycetes has recently been recognised and established as 'Ducellieriales' (Buaya & Thines 2023), comprising the known species D. chodatii (Ducellier) 8 ...
Wind-blown pollen (pollen rain) is a major contributor to element cycling in modern forests and aquatic ecosystems, particularly in high-latitude and acidic settings where nutrients are a limiting factor. The rich package of proteins, nitrogen and phosphorus residing within pollen is, nonetheless, inaccessible to most organisms, owing to the indigestible sporopollenin walls. Saprotrophic breakdown by fungi, and some non-fungal microorganisms, can make nutrients bioavailable, and represents a key trophic link in element cycling and the transfer of organic carbon. Little is known about when micro-saprotrophs first adapted to exploit pollen, thus establishing this crucial step in the evolution of modern terrestrial ecosystems. One approach is to examine the rich fossil record of palynomorphs. Here we describe translucent bodies referable either to fungi (Chytridiomycota) or water moulds (Oomycetes) within the pollen of glossopterid gymnosperms and cordaitaleans, and fern spores from silicified Permian (Guadalupian–Lopingian) peats of the Toploje Member, Bainmedart Coal Measures, Prince Charles Mountains, Antarctica. These probable holocarpic thalli or oospores exploited the nutrient-rich microgametophyte tissue of dispersed miospores in high-palaeolatitude wetlands. The exceptional preservation of fossil microorganisms in permineralised peats offers insights into the deep-time evolution of intimate ecological relationships, otherwise known only among extant biotas. Permineralisation has preserved sub-micron details of these delicate and cryptic saprotrophs that likely played key roles in cycling nutrients in the acidic forest mires of the Permian. Our study reveals that the extensive recapture of spore/pollen-derived nutrients via saprotrophic digestion was already at play in the high-latitude ecosystems of the late Palaeozoic.
... Ducellieria is primarily characterized by forming colourless, multicellular, coelastrum-like spherical aggregates, connected by hollow spines, and outward-directed spines (Kusel Fetzmann & Nouak 1981, Hesse et al. 1989. The spherical aggregate is formed at the tip of a discharge tube from an endobiotic non-septate holocarpic thallus (Kusel Fetzmann & Nouak 1981, Hesse et al. 1989, Stoyneva et al. 2013. Ducellieria chodatii recurs seasonally in parallel to the peak of the pollen bloom of Pinus and Picea species, but has only rarely been reported (Kusel Fetzmann & Nouak 1981, Hesse, Kusel Fetzmann & Carniel 1989, Gorbulin 2012, Stoyneva et al. 2013, Bancsó 2023. ...
... The spherical aggregate is formed at the tip of a discharge tube from an endobiotic non-septate holocarpic thallus (Kusel Fetzmann & Nouak 1981, Hesse et al. 1989, Stoyneva et al. 2013. Ducellieria chodatii recurs seasonally in parallel to the peak of the pollen bloom of Pinus and Picea species, but has only rarely been reported (Kusel Fetzmann & Nouak 1981, Hesse, Kusel Fetzmann & Carniel 1989, Gorbulin 2012, Stoyneva et al. 2013, Bancsó 2023. ...
... While the development of the endobiotic thalli ( Fig. 1A) seemed to show features of several genera, including Aphanomyces, Ducellieria, and Lagenidium, the development of the coelastrum-like form (Fig. 1A, B) was always in line with previous descriptions of D. chodatii (Kusel-Fetzmann & Nouak 1981, Kusel-Fetzmann & Carniel 1984, Hesse et al. 1989, Stoyneva et al. 2013. As we assume that multiple species of oomycetes were causing the endobiotic thalli in this study, only the coelastrum-like form is described here. ...
The genus Ducellieria (Ducellieriaceae) contains three species (D. chodatii, D. tricuspidata, D. corcontica), and a single variety (D. chodatii var. armata) of obligate endobiotic pollen parasites. These organisms have been first assigned to the green alga genus Coelastrum, as they form very similar spherical structures, but the observation of heterokont zoospores has led to their reclassification to the phylum Oomycota. However, despite their widespread nature, these organisms are only known from their descriptive morphology, and life cycle traits of some species still remain incompletely known. Only the type species, D. chodatii, has been rediscovered several times, but the phylogeny of the genus remains unresolved, since none of its species has been studied for their molecular phylogeny. At present the genus is still included in some algal databases. To clarify the evolutionary affiliation of Ducellieria, efforts were undertaken to isolate D. chodatii from pollen grains, to infer its phylogenetic placement based on nrSSU sequences. By targeted isolation, the pollen endoparasitoid was rediscovered from three lakes in Germany (Mummelsee, Okertalsperre, Knappensee). Apart from the typical coelastrum-like spheroids, oomycetes sporulating directly from pollen grains in a lagenidium-like fashion were observed, and molecular sequences of both types of oomycetes were obtained. Phylogenetic reconstruction revealed that coelastrum-like and lagenidium-like forms are unrelated, with the former embedded within the deep branching early-diverging lineages, and the later stage forming a distinct clade in Peronosporales. Consequently, the life cycle of D. chodatii needs careful revision using single-spore isolates of the species, to infer if previous lifecycle reconstructions that involve various different thallus types are stages of a single species or potentially of several ones.
... ariótákkal való közelebbi kapcsolatra utaló bélyegként értékelte. Ennek folyományaként született javaslat az aktuálisan elfogadott rendszerben előbb a korábban moszatgombákként ismert Phycomycetes (KUSEL-FETZMANN & NOUAK 1981), aztán az Oomycetes (HESSE et al. 1989) osztályba, majd az Oomycota törzsbe történő reklasszifikációjára (MOORE et al. 2011). STOYNEVA et al. (2013 kutatásai azon túl, hogy újabb ismeretekkel tették teljesebbé a Ducellieria chodatii egyedfejlődésének mechanizmusáról alkotott képet (pl. másodlagos ciszták leírása), csak megerősítették idézett szerzők álláspontját, azaz véleményük szerint is ennek a fajnak -az általuk alkalmazott rendszertani felosztásnak megfelelően -a Chromista reg ...
Kőszeg közelében, az Alsó-erdőben fellelhető tőzegmohás átmeneti láp közel három éve indult algológiai vizsgálata során 2022 tavaszán egy új, korábban még nem jegyzett faj került elő, a Ducellieria chodatii (Ducellier) Teiling. Fenyőpollen parazita lévén felbukkanása összefüggésbe hozható a környező fenyves, illetve fenyő elegyes állományok utóbbi időben tapasztalható fokozott pollentermelésével. Mind morfológiai szempontból, mind az élőhely környezeti adottságait illetően a vizsgálatok eredményei javarészt illeszkedtek a szakirodalomban fellelhető korábbi vonatkozó adatokhoz. Eltérésként említendő ezekhez képest az élőhely alacsonyabb térszíne, valamint kiemelendő az egyik mintaterület jelentősen átlag feletti vezetőképesség értéke. Mindezek az ismeretek a mellékelt képanyaggal együtt adalékul kívánnak szolgálni nem csak a D. chodatii hazai előfordulását jegyző, de a faj alaktani, fejlődéstani jellemzőit, valamint ökológiai igényeit feltáró kutatásokhoz is.
The Xanthophyceae, Eustigmatophyceae, and Raphidophyceae are three independent classes of stramenopile algae (Heterokontophyta or Ochrophyta); they are not closer related with each other. Most Xanthophytes are unicellular or colonial coccoid algae, others from multicellular filaments and or exhibit thalli composed of multinucleate siphons. The Eustigmatophyceae comprises only coccoid members which are very difficult to distinguish from the coccoid Xanthophytes. Freshwater Raphidophytes are rather distinct, because they form flagellated vegetative stages. The color of Xanthophytes and Eustigmatophytes is yellowish green due to the absence of the brown fucoxanthin, present in Raphidophytes and other stramenopile algae. Only the Eustigmatophytes lack chlorophyll c. Many Xanthophytes and Eustigmatophytes share that they predominately occur in terrestrial habitats, e.g. soil, representing a small group of terrestrial algae with their plastids obtained from an ancestral red alga by secondary symbiosis. For Raphidophytes only three genera are recognized in freshwater yet and they are observed within the plankton.
