Alternaria species in section Alternaria associated with Iris plants in China

Abstract

Plants of the Iris genus have been widely cultivated because of their medicinal, ornamental, and economic values. It commonly suffers from Alternaria leaf spot or blight disease leading to considerable losses for their commercial values. During an investigation of 14 provinces or municipalities of China from 2014 to 2022, a total of 122 Alternaria strains in section Alternaria were obtained from diseased leaves of Iris spp.. Among them, 12 representative strains were selected and identified based on morphological characterization and multi-locus phylogenetic analysis, which encompassed the internal transcribed spacer of rDNA region (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1 alpha (TEF1), RNA polymerase second largest subunit (RPB2), Alternaria major allergen gene (Alt a 1), an anonymous gene region (OPA10-2), and endopolygalacturonase gene (EndoPG). The strains comprised two known species of A. alternata and A. iridicola, and two new species of A. setosae and A. tectorum, which were described and illustrated here. Their pathogenicity evaluated on Iris setosa indicated that all the strains could induce typical Alternaria leaf spot or blight symptoms. The results showed that the virulence was variable among those four species, from which A. tectorum sp. nov. was the most virulent one, followed by A. setosae sp. nov., A. iridicola and A. alternata.

Two novel species and a new host record of Alternaria (Pleosporales, Pleosporaceae) from sunflower (Compositae) in Myanmar

“…Agreeing with Romain et al (2022) , the present species are also clearly distinguished based on a multigene sequence analysis, indicating which species belong to the section Alternaria . To date, this section includes more than 91 species, according to recent publications ( Gannibal and Lawrence (2016) ; Nishikawa and Nakashima (2020) ; Gou et al 2022 , 2023 ; Li et al 2023 ; Liao et al 2023 ; He et al 2024 ).…”

Four New Species of Small-Spored Alternaria Isolated from Solanum tuberosum and S. lycopersicum in China

“…There are 27 new species latterly defined as new members of sect. Alternaria [ 27 , 42 , 43 , 45 ]. In this study, four novel species ( A. lycopersici sp.…”

“…Since the 20th century, molecular approaches have been utilized to identify Alternaria species [ 22 , 23 , 24 , 25 ]. At present, species identification based on multi-locus phylogenetic analysis has been applied as a powerful classification tool to assist morphological taxonomy, which has resulted in a combination of both approaches to determine these species [ 20 , 26 , 27 , 28 ].…”

Morphological and phylogenetic analyses reveal two new Alternaria species (Pleosporales, Pleosporaceae) in Alternaria section from Cucurbitaceae plants in China

“…Small-spored Alternaria species are also frequently isolated from Cucurbitaceae in China ( Ma et al 2021 ). Woudenberg et al (2015) provided a clear and stable species classification of section Alternaria based on the genomic and multi-loci analyses, from which the species commonly produce concatenated conidia ( Norphanphoun et al 2021 ; Li et al 2022 ; Gou et al 2022 ). Consequently, the combination of morphology and molecular techniques provides a better understanding of species in section Alternaria ( Aung et al 2020 ).…”