New species and new findings of phoma-like fungi (Didymellaceae) associated with some Asteraceae in Russia

Abstract

<jats:p> The notable difficulties in the morphological identification of phoma-like fungi haveresulted in a poor understanding of the generic and species boundaries in this group of organisms.In most available mycofloristic and phytopathological studies, there is no reliable information onthe distribution of certain nonspecialized phomoid species on cultivated crops or wild plants. Boththe revision of existing data on the biodiversity and geographical distribution of phoma-like fungiassociated with Asteraceae in Russia and the acquisition of new knowledge according to modernconcepts of these fungi are therefore of great significance. The aim of this study was to identifyphoma-like strains from Asteraceae based primarily on phylogenetic analyses of the sequences offour loci (ITS, LSU, TUB, RPB2) as well as on traditional morphological approaches. The resultingphylogenetic trees revealed six well-supported monophyletic clades corresponding to six genera inthe family Didymellaceae: Ascochyta, Boeremia, Didymella, Neoascochyta, Nothophoma, andStagonosporopsis. The isolates were identified as As. kamchatica, B. exigua, B. exigua var. forsythiae,B. exigua var. linicola, D. americana, D. glomerata, D. macrophylla, D. pinodella, D. pomorum,D. rosea, Ne. desmazieri, Ne. paspali, No. quercina, St. dennisii, and St. inoxydabilis. Ascochytakamchatica sp. nov. was described as a new species. Three Didymella species (D.pinodella from Cirsium arvense, D. rosea from Sonchus arvensis, and D. macrophylla from Taraxacumofficinale), two Neoascochyta species (Ne. desmazieri from T. officinale and Ne. paspali fromAchillea millefolium) and St. dennisii from T. officinale were the first records of these phoma-likefungi in Russia. </jats:p>

Overview of Phoma-Like Fungi on Important Legumes (Papilionaceous Plants)

“…Molecular datasets have provided a better outlook towards the phylogenetic and evolutionary trends of phomoid fungi (Aveskamp et al 2008(Aveskamp et al , 2010aGomzhina et al 2020).…”

“…It is critical to note that the identification of these Phoma-like fungi was carried out mainly by morphological features or only 'based on the host'. However, such identification of the pathogen could be incorrect, since it is possible to encounter a similar but widely specialized saprotrophic or weakly pathogenic species (Gomzhina et al 2020). The role of host plant associations and morphological or cultural features on different substrates has not have specified importance any more in the identification of Phoma-like fungi.…”

Identification and pathogenicity analysis of leaf brown spot of Juglans regia in China

“…Nothophoma was described by Chen et al 3 There are currently 22 species in this genus. Many species in this genus are plant pathogens, and its members cause diseases in a wide variety of woody plants 3 – 5 . Several important fruits, including Chaenomeles sinensis , have been reported to be affected by Nothophoma genus fungi in Korea.…”