New species of Phaeomoniellales from a German vineyard and their potential threat to grapevine (Vitis vinifera) health

Abstract

Recently, the order Phaeomoniellales was established that includes fungi closely related to Phaeomoniella chlamydospora, a phytopathogen assumed to be the main causal agent of the two most destructive grapevine trunk diseases, Petri disease and esca. Other species of this order are reported as pathogens of other economically important crops, like olive, peach, apricot, cherry, plum, rambutan, lichee or langsat. However, they are rarely isolated and hence, little is known about their ecological traits and pathogenicity. During a 1-yr period of spore trapping in a German vineyard divided in minimally and intensively pruned grapevines, 23 fungal strains of the Phaeomoniellales were collected. Based on morphological and molecular (ITS, LSU and tub2) analyses the isolated strains were assigned to eight different species. Two species were identified as P. chlamydospora and Neophaeomoniella zymoides, respectively. The remaining six species displayed morphological and molecular differences to known species of the Phaeomoniellales and are newly described, namely Aequabiliella palatina, Minutiella simplex, Moristroma germanicum, Mo. palatinum, Neophaeomoniella constricta and N. ossiformis. A pathogenicity test conducted in the greenhouse revealed that except for P. chlamydospora, none of the species of the Phaeomoniellales isolated from spore traps is able to induce lesions in grapevine wood.

Dieback and decline pathogens of olive trees in South Africa

“…The fact that most genera with more than one species in the Phaeomoniellales were well-supported in phylogenetic analyses of the LSU region suggests that this region is currently adequate for the delineation of genera in the Phaeomoniellales . Kraus et al (2020) recently described six new species of known genera in the Phaeomoniellales collected in German vineyards. Such collections and descriptions broaden the available knowledge on genera in the Phaeomoniellales and help to consolidate generic concepts within this order.…”

“…Neophaeomoniella zymoides , although initially reported as an endophyte of pine needles in Korea ( Lee et al 2006 ), was later associated with necrotic wood of plum trees in South Africa (Limpopo Province), and shown to cause significant lesions when inoculated on peach shoots, but not on plum ( Damm et al 2010 ). More recently this species was also recovered from spore traps in German vineyards, but found to be non-pathogenic to grapevine ( Kraus et al 2020 ). Of the remaining Phaeomoniellales species collected from olive trees in this study, one is a new genus here described as Vredendaliella , and five are previously undescribed species of Xenocylindrosporium .…”

Fungal trunk diseases of fruit trees in Europe: pathogens, spread and future directions

“…However, most FTD pathogens are primarily spread through the dispersion of airborne spores. Depending on the fungal species, conidia or ascospores are released from pycnidia or perithecia embedded in the surfaces of dead wood and/or in bark tissues (Eskalen and Gubler, 2001;Rooney-Latham et al, 2005;Úrbez-Torres et al, 2014;van Niekerk et al, 2010;Kraus et al, 2020). This inoculum is released under favourable environmental conditions, which have been mostly associated with rain events and/or high relative humidity along with temperatures above freezing, which also favour spore germination (Úrbez-Torres et al, 2010a;van Niekerk et al, 2010).…”

Fungal species associated with grapevine trunk diseases in Washington wine grapes and California table grapes, with novelties in the genera Cadophora, Cytospora, and Sporocadus

“…With physical culture collections, population genetics and genomics analyses can be conducted ( Péros and Berger, 1999 ; Smetham et al., 2010 ; Travadon et al., 2012 ; Gramaje et al., 2013 ; Onetto et al., 2022 ), the pathogenicity of fungal isolates can be assessed experimentally ( Cloete et al., 2015 ; Lawrence et al., 2015 ; Travadon and Baumgartner, 2015 ; Baloyi et al., 2018 ), interactions between species can be evaluated under controlled conditions ( Lawrence et al., 2018b ; Silva-Valderrama et al., 2021 ), and molecular databases including the ecological guild of species can be built ( Lawrence et al., 2017b ). Further, new pathogenic species can be described and linked with type specimens deposited in public repositories ( Travadon et al., 2015 ; Lawrence et al., 2017a ; Moyo et al., 2018 ; Kraus et al., 2020 ).…”