Morphological and molecular characterization of Langdonia walkerae sp. nov. infecting Aristida stricta and A. beyrichiana in longleaf pine-grassland ecosystems in the southeastern USA

Abstract

A smut fungus that hinders wiregrass restoration efforts in longleaf pine-grassland ecosystems was collected from Aristida stricta and A. beyrichiana (Poaceae) in three states in the southeastern USA. Morphological and phylogenetic characteristics of this fungus were examined. These data show that the specimens from both plant species were infected by the same fungus and represent a new species of Langdonia. The new species differs morphologically from other species of Langdonia by teliospores being solitary and not compacted into spore balls. Spore wall ornamentation and teliospore size also differ from other Langdonia species. Phylogenetic analyses of DNA sequences of the ITS, LSU, and EF-1α supported separation of the species from A. stricta and A. beyrichiana from other Langdonia species. Based on these results, a new species, Langdonia walkerae, is proposed.

Smut fungus (Langdonia walkerae) incidence is lower in two bunchgrass species (Aristida stricta and A. beyrichiana) after fires early in the year

“…The genus Langdonia currently encompasses nine species of smut fungi that have all been isolated from Aristida species (Alqurashi et al, 2021). Smut fungi are characterized by dark, thick‐walled sexual and resting (overwintering) spores called teliospores.…”

“…Recently, this fungus was identified as Langdonia walkerae Alqurashi, J. Kerrigan & K.G. Savchenko in both A. stricta and A. beyrichiana (Alqurashi et al, 2021). Infection by L. walkerae occurs during the flowering period and results in the replacement of seeds by fungal sori, thereby decreasing seed output (Alqurashi, 2020).…”

Proposal of Two New Combinations, Twenty New Species, Four New Genera, One New Family, and One New Order for the Anamorphic Basidiomycetous Yeast Species in Ustilaginomycotina

“…The genus Langdonia includes ten species, namely, L. aristidae, L. aristidaria, L. aristidicola, L. clandestina, L. confusa, L. fraseriana, L. goniospora, L. inopinata, L. jejuensis, and L. walkerae (Begerow et al, 2014;Wang et al, 2015;Alqurashi et al, 2021), among which, nine species have a sexual stage except L. jejuensis. Seven of them have rDNA sequences (Supplementary Table 2) and differ from each other by 1-22 nt (0.16-3.6%) and 7-82 nt (1-12%) in the D1/D2 and ITS regions, respectively.…”

“…Strain CGMCC 2.6313 are placed in the Langdonia clade and phylogenetically distinct from other known species (Figures 1, 3). The newly published species Langdonia walkerae was described based on sexual characters and molecular data with ten specimens collected from Aristida stricta and Aristida beyrichiana (Poaceae) in the southeastern United States in 2018 (Alqurashi et al, 2021). CGMCC 2.4680, with the asexual yeast stage, was isolated from the leaf of an unidentified plant in China in September 2012.…”

“…Langdonia walkerae was described by Alqurashi et al (2021) based on a sexual stage. A yeast strain, CGMCC 2.…”