0000000000778534
AUTHOR
Kusum Kumari Singh
ITS region of the rDNA of Pythium rhizosaccharum sp. nov. isolated from sugarcane roots: taxonomy and comparison with related species.
Pythium rhizosaccharum (F-1244) was isolated from soil samples taken in the rhizosphere of sugarcane (Saccharum officinarum) in the north-eastern India. This species is characterized by its smooth-walled, spherical sporangia and rarely formed sexual structures. When formed, the antheridial branches wrap around the oogonia and soon disappear after fertilization. The internal transcribed spacer (ITS) region of its rDNA is comprised of 904 bases. The taxonomical description of this new species and its comparison with related species are given here, together with the nucleotide sequences of the ITS1 and ITS2, and the 5.8S gene of its ribosomal nuclear DNA.
Pythium campanulatumsp. nov., isolated from the rhizosphere of maize, its taxonomy, ITS region of rDNA, and comparison with related species
Pythium campanulatum sp. nov. was isolated from some soil samples taken in the rhizosphere of maize (Zea mays) in north-eastern India. This species is characterized by the absence of zoospores and sporangia, antheridial branches wrapping around the oogonia leaving one to two campanulate antheridial cells after fertilization, and aplerotic oospores. The ITS region of its rDNA is comprised of 922 bases. This oomycete is closely related to Pythium orthogonon, Pythium nunn and Pythium toruloides. However, it has its own characteristic features and is completely devoid of zoospores. Taxonomic description of this new species and its comparison with related oomycetes, together with the sequence of…