The mycobiota of needles and shoots of silver fir (Abies alba Mill.) with symptoms of Herpotrichia needle browning in the Tatra Mts. (Poland)

Abstract

The European silver fir (Abies alba Mill.) has the largest distribution area of all the European species of fir. It is the only species of this type found in the Carpathian Mts., including their highest range - the Tatras, where it constitutes one of the main components of lower montane forests. In certain sections of the Carpathian Mountains fir stands are affected by the competitive pressure of beech. This may be due to climate change, as well as biotic factors such as plant diseases. One such disease is Herpotrichia needle browning. The goal of the present research was to assess the occurrence of Herpotrichia needle browning in the Tatra National Park and determine the species composition of fungi colonizing symptomatic needles and shoots. Symptoms of the disease were observed across the entire research period, i.e., from May to mid-September 2019. They included the wilting of the needles with subsequent mycelial growth on the remains, as well as shoot deformation. The mycological analysis of the needles and shoots of A. alba resulted in the isolation of 22 fungal taxa. In the case of the needles and shoots, which showed symptoms of infection, the most frequent species of fungus was Sydowia polyspora (Bref. & Tavel) E. Müll., followed by Alternaria alternata (Fr.) Keissl. and Rhizosphaera macrospora Gourb. & M. Morelet. Herpotrichia needle browning seems to be triggered by a complex disease resulting from synergistic interaction of several fungal pathogens

Fungi associated with shoot dieback of Pinus mugo subsp. mugo in the Polish Tatra Mountains

“…This pathogen is a known endophyte of angiosperms, especially Fagus sylvatica L. (Nugent et al., 2005) on which it can cause strip‐cankers and wood decay (Granata & Sidoti, 2004). Biscogniauxia nummularia has also been reported from conifers such as pine, fir and Douglas fir (Bartnik et al., 2021; Bußkamp et al., 2020; Patejuk et al., 2022; Petrini, 1985; Pusz et al., 2020). Our results support these findings, as this study had the first report of B. mediterranea on P. mugo .…”

A New Species of Biscogniauxia Associated with Pine Needle Blight on Pinus thunbergii in China

“…But B. mediterranea has been reported as a pathogen of Pinus sylvestris in Spain [58]. In 2020, it was also isolated from a twig of Abies alba with needle browning symptoms in Poland [59]. This fungus has long been considered as an endophyte in all aerial organs (rarely in leaves) of oak trees and has an incubation period without symptoms [60].…”

Silver Fir (Abies alba Mill.): Review of Ecological Insights, Forest Management Strategies, and Climate Change’s Impact on European Forests

“…due to other pathogens have been observed in Europe in recent years. Increased forest degradation of silver fir forests, presumably due to climate change, was found, for example, due to infection of the phytopathogenic bacterium Lelliottia nimipressuralis in Ukraine [246] or the fungi responsible for Herpotrichia needle browning, including Nematostoma parasiticum [247]. Fir stands can also be infested by the hemiparasitic mistletoe (Viscum album L.), which attacks a wide range of woody plants [248][249][250].…”