Redefining genera of cereal pathogens: Oculimacula, Rhynchosporium and Spermospora

Abstract

The taxonomy of Oculimacula, Rhynchosporium and Spermospora is re-evaluated, along with that of phylogenetically related genera. Isolates are identified using comparisons of DNA sequences of the internal transcribed spacer ribosomal RNA locus (ITS), partial translation elongation factor 1-alpha (tef1), actin (act), DNA-directed RNA polymerase II largest (rpb1) and second largest subunit (rpb2) genes, and the nuclear ribosomal large subunit (LSU), combined with their morphological characteristics. Oculimacula is restricted to two species, O. acuformis and O. yallundae, with O. aestiva placed in Cyphellophora, and O. anguioides accommodated in a new genus, Helgardiomyces. Rhynchosporium s. str. is restricted to species with 1-septate conidia and hooked apical beaks, while Rhynchobrunnera is introduced for species with 1–3-septate, straight conidia, lacking any apical beak. Rhynchosporium graminicola is proposed to replace the name R. commune applied to the barley scald pathogen based on nomenclatural priority. Spermospora is shown to be paraphyletic, representing Spermospora (type: S. subulata), with three new species, S. arrhenatheri, S. loliiphila and S. zeae, and Neospermospora gen. nov. (type: N. avenae). Ypsilina (type: Y. graminea), is shown to be monophyletic, but appears to be of minor importance on cereals. Finally, Vanderaaea gen. nov. (type: V. ammophilae), is introduced as a new coelomycetous fungus occurring on dead leaves of Ammophila arenaria.

New Strain of Cyphellophora olivacea Exhibits Striking Tolerance to Sodium Bicarbonate

“…Other species, such as C. guyanensis, C. oxyspora, C. sessilis, C. jingdongensis and C. olivacea were isolated from plant materials or non-biological substrates [43,47,49,60]. The genus is continuously expanding with the introduction of new species and with the occasional transfer from other genera [59,61,62].…”

“…C. eugeniae and C. hylomeconis were transferred to new genera, as Aphanophora eugeniae and Camptophora hylomeconis [34]. According to Crous et al, C. vermispora is identical to C. aestival [59]. Finally, we used the sequences of 27 ex-type strains to build phylogenetic trees (Supplementary Table S1).…”

Development of Researches at Phytopathology Lab From 1971 to 2021

“…Болезни встречаются практически во всех кукурузосеющих регионах мира [9,19,34,37]. Фузариоз ухудшает посевные качества семян, пищевые свойства зерна и продуктов его переработки (снижается содержание крахмала и жиров, повышается содержание белка в зерне), приводит к накоплению микотоксинов [28].…”

Wild barley (Hordeum spontaneum) and landraces (Hordeum vulgare) from Turkey contain an abundance of novel Rhynchosporium commune resistance loci

“…Therefore, wild grass species can serve as a reservoir of potentially virulent isolates and primary hosts to complete its sexual cycle (Linde et al 2016;Seifollahi et al 2018), whereas the secondary host remains unidenti ed. In a recent publication, Crous et al (2021) proposed renaming R. commune to R. graminicola.…”