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The diversity of easy-to-study organisms (e.g. vascular plants) is often used as a proxy for the diversity of other organisms whose investigation needs more effort, time and specialist knowledge. Some previous studies have found positive relationships between plant and macrofungal diversity and thus support this approach, while others question this practice. Our aim was to explore the possibility of using plant diversity as surrogate for macrofungal diversity in the forests of the Pannonian ecoregion. A total of 19 permanent plots in north-east Hungary were sampled for vascular plants and macrofungi. The effect on macrofungal abundance and diversity, of plant evenness and richness as well as degradation level was tested using generalized linear models. Species richness of macrofungi assemblages proved to be independent of the diversity and naturalness of vascular plant communities; however, there was congruence in the composition of the two communities. In contrast to diversity, macrofungi abundance was significantly negatively correlated to plant species richness. There was a hump-backed relationship between the abundance of terricolous macrofungi and the degradation level estimated on the basis of the occurrence of vascular plants, although degradation did not influence the abundance of lignicolous macrofungi. Our results question the reliability of decisions on nature conservation actions based on a few groups of easy-to-observe organisms, and underline the necessity of studying as wide a range of taxonomic groups as possible.

Macrofungi play an extraordinarily important role in the catalysis of the nutrient cycle of deciduous and coniferous forests. Habitat degradation adversely influences the number of fruiting bodies of macrofungi and diminishes the diversity of the fungal community. The diversity of the terricolous- and lignicolous macrofungi assemblages were compared in stands of semi-natural and two plant associations modified by humans in different degrees in North-East Hungary. We used data from 15 permanent plots that were sampled for vascular plants and macrofungi. Rank-abundance curves and Rényi’s diversity profiles were applied for diversity research. The results indicated that structure and diversity of the terricolous macrofungi assemblages were mainly influenced by climatic and habitat conditions and the degradation of the plant associations to a lesser degree. The diversity of lignicolous macrofungi was primarily affected by the continuous presence, quality, and quantity of deadwood. Accordingly, the form and degree of forest management, as well as the age of the growing stocks, influenced community structure. If nature conservation planning and conservation activity are based on those biodiversity indicators which are good proxies for macrofungi biodiversity, the latter might be optimal for preserving macrofungi biodiversity.

The detailed chemical analysis of the methanol extract of Meripilus giganteus (Pers.) P. Karst. led to the isolation of two new cerebrosides, mericeramides A (1) and B (2) together with cerebroside B (3), ergosterol (4), 3β-hydroxyergosta-7,22-diene (5), cerevisterol (6), 3β-hydroxyergosta-6,8(14),22-triene (7), 3β-O-glucopyranosyl-5,8-epidioxyergosta-6,22-diene (8) and (11E,13E)-9,10-dihydroxy-11,13-octadecadienoic acid (9). The structures of the compounds were determined on the basis of NMR and MS spectroscopic analysis. Mericeramide A (1) is the first representative of halogenated natural cerebrosides. The isolated fungal metabolites 1–9 were evaluated for their antioxidant activity using the oxygen radical absorbance capacity (ORAC) assay. Compounds 2, 5 and 9 proved to possess considerable antioxidant effects, with 2.50 ± 0.29, 4.94 ± 0.37 and 4.27 ± 0.05 mmol TE/g values, respectively. The result obtained gives a notable addition to the chemical and bioactivity profile of M. giganteus, highlighting the possible contribution of this species to a versatile and balanced diet.