Ectomycorrhizal Colonisation in Declining Oak Stands on the Krotoszyn Plateau, Poland

Abstract

We describe the ectomycorrhizal (ECM) root tips and the diversity of mycorrhizal fungal species at three English oak (Quercus robur) sites (two 120 year old sites and one 60 year old site). The three oak stands in decline, located in western Poland, were characterized by a low degree of vital ECM colonization: 30.2%, 29.1% and 25.6% at Krotoszyn (K), Piaski (P) and Karczma Borowa (KB), respectively. DNA (ITS) barcoding revealed a total of 18 ECM fungal species. Based on exploration types, ectomycorrhizae were classified with respect to ecologically relevant features. The contact type was significantly correlated with C:N and Corg, while the short distance type was correlated with Ca, phosphorus (P2O5) and pH. The medium distance exploration type was significantly correlated with fine-grained soil particle size fractions: coarse silt (0.05–0.02 mm) and fine silt (0.02–0.002 mm), and clay (<0.002 mm). The long distance type showed a similar pattern to the medium distance smooth type, but was also correlated with nitrate (N). The values of biometric root parameters of oak trees at the analysed forest sites were arranged as follows: K > P > KB, and were opposite to the condition of the tree crowns. A negative correlation of vital ECM root tip abundance with the crown health status of oaks was observed, whereas higher ECM diversity reflected better crown health in the oak stands studied.

The ectomycorrhizal community of urban linden trees in Gdańsk, Poland

“…Considering the mycorrhization degree, only class R3 had significantly fewer vital ectomycorrhizal tips than other classes. These data confirmed the data obtained by studying the English oak trees [39], where fine roots of most declining trees had a lower proportion of vital and ectomycorrhizal tips.…”

Effect of Deadwood on Ectomycorrhizal Colonisation of Old-Growth Oak Forests

“…Moreover, Tomentella species have been found to occur more often in dead wood in intermediate decay phases than in late decay phases [50,51]. CWD supports a relatively high abundance of ECM fungi from the lineages Tomentella-Thelephora (Thelephorales) [9,52], which are dispersed by soil microarthropodes [9,11,[53][54][55].…”

“…The second most numerous mycorrhizae were formed by P. nemoralis, belonging to the phylum Ascomycota. This fungus forms hypogeous fruiting bodies and, to the best of our knowledge, the first record of this fungus in Poland was noted in our recent study [11]. Due to very limited data in this context [56,57], we can only presume that this species is a short-distance exploration type of mycelium, like the majority of ectomycorrhizal ascomycetous species [26].…”

“…Nowadays, one of the most important issues regarding European oaks is forest decline. Differences in the degree of mycorrhizal colonization are shown in Quercus robur L. stands in relation to disturbances caused by abiotic and biotic factors (health status) [11]. The oak decline phenomenon is a complex disease, caused by several biotic and abiotic factors, often acting synergistically [12,13].…”

Microhabitat and ectomycorrhizal effects on the establishment, growth and survival ofQuercus ilexL. seedlings under drought

“…In fact, [46] found lower abundance of extramatrical hyphae and less dense mantles in Phytopththora cambivora infected and declining chestnut stands, compared to non-infected chestnut stands. Similarly, [47] found that declining Quercus robur stands were associated with less long-distance and more short-distance exploration types (contact, short and medium) than what they found in healthier Q. robur stands. This potential role of ECM species with longer mycelia in reducing pathogen infection could help to understand the positive relation between ECMsm and seedling survival and height found in our experiment (Table 2).…”