# New Detection Method for Fungal Infection in Silver Fir Seeds
## 2 Silver Fir in the Bialowieza Forest
Thus, it can be used in practical forestry outside the mountainous part of the range of the studied species, and not only in the Bialowieza Forest region, but in other parts of Poland first of all in the natural forest region Mazury-Podlaskie (II). This situation becomes especially important and relevant against the background of the current mass extinction of Norway spruce (_Picea abies_), especially in the northeastern part of its range [38; 39]. The modern range of silver fir in Poland began in the sub-Boreal period of the Holocene and ended about 2000 years ago in the sub-Atlantic [34; 40]. However, in the postglacial or in the so-called Little Ice Age (1300-1850), which came after the climatic optimum of the Holocene (about 800-1300 BP), Norway spruce (_Picea abies_), a typical boreal species, displaced the silver fir, growing in admixture with the main species [28]. Now, under conditions of global warming, only silver fir, which is similar to _P. abies_ in terms of ecological and biological properties, can be a possible alternative to this species. We have already mentioned the favorable growth conditions for the silver fir in Tisovik, and this area was the source of seeds for our study [41], as well as from two other artificial silver fir stands of unknown geographical origin in the Polish part of the Bialowieza Forest, but of an older age [42]. It is known that one of the main stresses faced by _A. alba_ is low winter temperatures [18; 35]. According to the predictive model of [PERSON] et al. [43], under the conditions of modern climate, silver fir in Europe is favored, as predictions are for warming characterized by a sharp increase in winter temperatures with a constant amount of precipitation [36; 44]. [PERSON] et al. [45] also came to a similar conclusion, and they classified _A. alba_ as a \"winner\" while modeling the ranges of major European tree species by 2061-2080 and the level of threat they may face under different scenarios of climate change. However, at present, there is still not enough silvicultural experience of silver fir in northern Poland [46], although, in the middle of the 20 th century, it grew on small plots, at least in 22 forestry enterprises in the western and middle part of the Mazury-Podlaskie forest region of northeastern Poland [19]. A serious problem with efficient use of the germplasm of silver fir from Tisovik is that a low percentage of silver fir seeds can germinate. According to [PERSON] [29; 32], this ranges from 12.8% to 17.5%, which are rates similar to the 12.6% reported by [PERSON] et al. [47] for the Tisovik population [47]. These authors also noted that this can vary from tree to tree (2.6% to 40.0%). Another negative factor significantly affects the quality of silver fir seeds from Tisovik. According to [PERSON] [29; 32], the percentage of damage to mature seeds by the larvae of _Megastigmus suspectus_ [PERSON], _Resseliella picea_ [PERSON], and _Barbara herrichina_ [PERSON] is very significant, reaching the range of 62-77%. It is not unreasonable to assume that these pests have a complex of associates, represented by pathogenic fungi, capable of infecting seeds and other parts of trees. A similar situation, for example, takes place with Siberian fir (_A. sibrica_ [PERSON]), which is related to _A. alba_. In recent years, it has been dying from the combined action of the ususuri polygraph (_Polygraphus proximus_ [PERSON]) and associated ophiostomatoid fungi [48; 49]. According to Russian researchers, this biotic tandem represents a new threat to fir forests in Siberia and throughout Europe [48]. That is why it is so important to have a tool such as the electronic nose to assess seeds of silver fir. This will make it possible to determine the degree of their infection with pathogenic organisms quickly and take measures in advance to anticipate the influence of this negative factor, which can significantly reduce the germination rate of seeds. This will facilitate sufficient healthy planting material for a unique population of relict silver fir.