Phytopythium sindhum 137 Persoonial Reflections

Fems Microbiology Letters, 2006

Pythium spiculum sp. nov. was isolated from soil samples taken in a vineyard in the Burgundian region of France and from different locations in Spain and Portugal. The oomycete has spiny oogonia and does not sporulate readily. It resembles Pythium mamillatum Meurs, but has its own distinguishing characteristics. It also exhibits sickle-shaped as well as spherical appressoria which at times are associated with sex organs like those found in Pythium abappressorium Paulitz and Pythium contiguanum Paul. Sequencing of the internal transcribed spacer region of its nuclear ribosomal DNA and a close look at its morphological characters have now enabled us to describe it as a new species. The internal transcribed spacer region of its rRNA gene sequence is comprised of 945 bases. This oomycete is closely related to the members that form ornamented or spiny oogonia like Pythiummamillatum, Pythium spinosum and Pythium irregulare but also with those producing smooth-walled oogonia like Pythium paroecandrum, Pythium sylvaticum and Pythium cylindrosporum. Taxonomic description of this new species, its comparison with related oomycetes, the sequence of the internal transcribed spacer region of its rRNA gene and the phylogenetic tree, are given here.

Journal of General Plant Pathology, 2005

Isolates of Pythium graminicola and related species were differentiated using restriction fragment length polymorphism (RFLP) analyses of the internal transcribed spacer (ITS) regions of rDNA and the cytochrome c oxidase subunit II (COX II) gene. These sequences were used in subsequent phylogenetic analyses. Finally, the phylogenetic placement of species was compared to that determined from morphological characteristics. The 62 isolates tested were divided into seven groups, A-G, based on RFLP analysis of the rDNA-ITS region. In the RFLP analysis of the COX II gene, isolates were divided into groups similar to those based on ITS-RFLP. Groups A and B were each separated into two additional subgroups. Grouping of isolates based on RFLP analyses agreed with the morphological differentiation. Groups A, B, D, E, F, and G were identified as P. graminicola, P. arrhenomanes, P. aphanidermatum, P. myriotylum, P. torulosum, and P. vanterpoolii, respectively. Group C was closely related to group B based on phylogenetic analysis of the rDNA-ITS region and the COX II gene and is similar to P. arrhenomanes. Each of the other species occupied their own individual clades. Although P. arrhenomanes is morphologically similar to P. graminicola, our phylogenetic analyses revealed that it was evolutionarily distant from P. graminicola and more closely related to P. vanterpoolii. Our analysis also revealed that P. torulosum with smaller oogonia is more closely related to P. myriotylum with large oogonia than to P. vanterpoolii, which forms smaller oogonia and is morphologically similar to P. torulosum. P. aphanider-matum with large oogonia and aplerotic oospores was not related to the morphologically similar species P. myriotylum. Results suggest that P. graminicola and related species are phylogenetically distinct, and molecular analyses, in addition to morphological analyses, are necessary for the accurate taxonomic placement of species in this complex.

Transactions of the British Mycological Society, 1988

Biosciences, Biotechnology Research Asia, 2021

The currents study evaluated the morphology (apperture, size, perine structures and surface ornamentation) of treated spores of 45 selected fern species from the Western Ghats of India, using Scanning Electron Microspcopy (SEM). Twenty-six species of fern spores were trilete type, while 19 of them had monolete aperture types. The size of the spore were found to be highly variable (20X20μm to 60X60μm) with an average mean spore size of 44 μmX38μm. Furthermore the spores were found to have a highly diverse perine ornementaion with 11 different types of perine structures. Gammate and psilate type of perine ornamentation, and Globose and ellipsoidal spore shape were found to be the most common within the studies fern spore samples. The variability found in the spore ultrastructure and perispore ornamentation of the selected pteridophytes species reflects the morphological differences observed in the sporophyte. The spores could be an important source of characteristics with systematic v...

Cryptogamie, Mycologie, 2016

We analyzed the morphology and phylogenetic placement of six isolates of Phytopythium belonging to P. helicoides, P. palingenes and P. vexans that were isolated from water bodies and substrates used for hydroponically grown crops. The molecular data are from the partial large subunit and the complete internal transcribed regions of the ribosomal DNA. These three species are characterized by the presence of ovoid to globose zoosporangia with papillae, internal proliferation as in Phytophthora and mode of zoospore discharge as in Pythium. All isolates showed high morphological and phylogenetic similarity with members of the Clades II and III of Phytopythium. In this paper, Phytopythium palingenes is included for the first time in phylogenetic analyses and our ITS and LSU phylogenies indicated that Aquaperonospora taiwanensis is a synonym of Phytopythium helicoides.

Fungal …, 2008

L. (2008). Morphology, taxonomy, and phylogenetic analysis of a new species of Pythium isolated from France. Fungal Diversity 28: 55-63.

Journal of Yeast …, 2011

Filamentous fungi comprehend a heterogeneous group of heterotrophic microorganisms that act as saprobes or parasites or, less frequently as symbionts living in association with other organisms. Water samples obtained seasonally from April 2010 to March 2011 at sixteen different sites of Dal Lake, Kashmir were serially diluted five folds followed by spread plate technique for the isolation of filamentous fungi, spreading 0.1 ml inoculum from the serial dilution tubes on the Petri dishes containing Rose-Bengal Streptomycin Agar medium. Twenty three (23) species of fungi namely Penicillium caseicolum, P. commune, P. chrysogenum, P. funiculosum, P. lilacinum, P. olivicolor, P. dimorphosporum, Penicillium sp. I, Penicillium sp. II, Penicillium sp. III, Penicillium sp. IV, Aspergillus flavus, A wentii, Aspergillus sp. Fusarium sp. Rhizopus sp. Acremonium sp. and Mucor sp. belonging to five genera were recovered from the Lake water samples. Penicillium and Aspergillus were the most dominant genera with a total of 11 and 8 species respectively. The most prevalent species was P. chrysogenum with its occurrence at all sixteen (16) sampling stations and a highest total of seventeen species was recorded at site 16 (Pokhribal Nallah II).

Persoonia - Molecular Phylogeny and Evolution of Fungi, 2012

Novel species of microfungi described in the present study include the following from Australia: Phytoph thora amnicola from still water, Gnomoniopsis smithogilvyi from Castanea sp., Pseudoplagiostoma corymbiae from Corymbia sp., Diaporthe eucalyptorum from Eucalyptus sp., Sporisorium andrewmitchellii from Enneapogon aff. lindleyanus, Myrmecridium banksiae from Banksia, and Pilidiella wangiensis from Eucalyptus sp. Several species are also described from South Africa, namely: Gondwanamyces wingfieldii from Protea caffra, Montagnula aloes from Aloe sp., Diaporthe canthii from Canthium inerne, Phyllosticta ericarum from Erica gracilis, Coleophoma proteae from Protea caffra, Toxicocladosporium strelitziae from Strelitzia reginae, and Devriesia agapanthi from Agapanthus africanus. Other species include Phytophthora asparagi from Asparagus officinalis (USA), and Diaporthe passiflorae from Passiflora edulis (South America). Furthermore, novel genera of coelomycetes include Chrysocrypta corymbiae from Corymbia sp. (Australia), Trinosporium guianense, isolated as a contaminant (French Guiana), and Xenosonder henia syzygii, from Syzygium cordatum (South Africa). Pseudopenidiella piceae from Picea abies (Czech Republic), and Phaeocercospora colophospermi from Colophospermum mopane (South Africa) represent novel genera of hyphomycetes. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.