Kaja Rola

Enhanced concentrations of elements and secondary metabolites in Viola tricolor L. induced by arbuscular mycorrhizal fungi

Background and AimsViola tricolor L. (heartsease, wild pansy) is a valuable medicinal plant obtained for pharmaceutical purposes by cultivation. Given that the species is usually strongly colonized by arbuscular mycorrhizal fungi (AMF), we tested in a pot experiment whether these microorganisms were able to influence V. tricolor mass, vitality, and the concentrations of selected elements, phenolic acids and flavonoids.MethodsThe following treatments were prepared: (1) control: sterile soil without AMF inoculation; (2) Rhizophagus irregularis BEG144; (3) Funneliformis mosseae BEG12; and (4) both isolates. Using a combination of physiological, phytochemical and biophysical methods, we evaluated the effects of these AMF on the performance of heartsease.ResultsThe intensity of mycorrhizal colonization and arbuscule formation was higher when F. mosseae and R. irregularis were introduced separately than when both isolates were present. None of the AMF treatments had an impact either on V. tricolor vitality as expressed by photosynthetic performance index (PI) or on its shoot and root mass. However, in general, a negative correlation was found between the extent of mycorrhizal colonization and shoot mass. We found AMF species specificities in their influence on element, phenolic acid and flavonoid concentrations. Viola tricolor showed no response to F. mosseae. The plants inoculated with R. irregularis had higher concentrations of P, Zn, Mg, and Ca, as well as p-hydroxybenzoic acid and rutin, in comparison to control. Dual AMF species inoculation increased concentrations of Cu, Mg and rutin.ConclusionsThe enhanced production of secondary metabolites in V. tricolor shoots may be due to improved mineral nutrition by AMF and/or a result of general plant defense reaction to fungal colonization. The tendency towards biomass decrease in AMF treatments could be explained by the allocation of plant carbon both to the maintenance of symbionts and enhanced production of secondary compounds.

Response of the lichen Cladonia rei Schaer. to strong heavy metal contamination of the substrate

The phenomenon of mass occurrence of the lichen Cladonia rei in extremely contaminated post-smelting slag dumps was studied in relation to metal accumulation capacity of this lichen. The research was aimed to evaluate the relationships between element contents in the thalli and in the corresponding substrate. The study was conducted in terms of a wide spectrum of Zn, Cd, Pb and As contents. The concentrations of these elements in the lichen thalli and substrate samples were measured. Various regression models were considered to find the best fitted one that greatly reflects the dependencies. Various Cladonia species and the hyperaccumulator Diploschistes muscorum were also included in the study for comparison purposes. Specific non-linear regression models described by a power function reflected relationships between Zn and Cd contents in C. rei thalli and in the host substrate in the most reliable way. The relationship for As was also noted, but none significant model was found. Contrarily, Pb concentrations in the thalli varied independently of the metal levels in the substrate. Nevertheless, the concentrations of all measured heavy metals in C. rei thalli are relatively low considering the frequently enormous substrate contamination. Different Cladonia species demonstrated a generally similar accumulation capacity and could be considered as weak accumulators. The restrained accumulation pattern may be one of the important attributes of C. rei which facilitates its colonisation of extremely contaminated dumps. This finding highlights ecological importance of this species as stable and resistant pioneer in such affected sites.

Root-inhabiting fungi in alien plant species in relation to invasion status and soil chemical properties

In order to recognize interactions between alien vascular plants and soil microorganisms and thus better understand the mechanisms of plant invasions, we examined the mycorrhizal status, arbuscular mycorrhizal fungi (AMF) colonization rate, arbuscular mycorrhiza (AM) morphology and presence of fungal root endophytes in 37 non-native species in Central Europe. We also studied the AMF diversity and chemical properties of soils from under these species. The plant and soil materials were collected in southern Poland. We found that 35 of the species formed AM and their mycorrhizal status depended on species identity. Thirty-three taxa had AM of Arum-type alone. Lycopersicon esculentum showed intermediate AM morphology and Eragrostis albensis developed both Arum and Paris. The mycelia of dark septate endophytes (DSE) were observed in 32 of the species, while sporangia of Olpidium spp. were found in the roots of 10. Thirteen common and worldwide occurring AMF species as well as three unidentified spore morphotypes were isolated from trap cultures established with the soils from under the plant species. Claroideoglomus claroideum, Funneliformis mosseae and Septoglomus constrictum were found the most frequently. The presence of root-inhabiting fungi and the intensity of their colonization were not correlated with soil chemical properties, plant invasion status, their local abundance and habitat type. No relationships were also found between the presence of AMF, DSE and Olpidium spp. These suggest that other edaphic conditions, plant and fungal species identity or the abundance of these fungi in soils might have an impact on the occurrence and intensity of fungal root colonization in the plants under study.

Cryptogamic community structure as a bioindicator of soil condition along a pollution gradient.

This study aims to determine changes in the structure of cryptogamic vegetation of poor psammophilous grassland along a pollution gradient near a zinc smelter to evaluate the potential of species assemblages as bioindicators of soil condition. Lichens and bryophytes were examined in study plots along six transects in four distance zones, and the physicochemical properties of corresponding soil samples were analysed. Four different responses of species to substrate contamination were identified, with a distinct group of species resistant to and favoured by metal contamination. Although species richness decreases as one approaches the smelter, the gradual replacement of certain sensitive species by resistant ones was observed along the pollution gradient. The results enabled us to develop a useful tool to diagnose strongly polluted sites. Two different cryptogamic assemblages of well-recognised key species characteristic for strongly polluted and lightly polluted sites were distinguished. We conclude that cryptogamic community structure clearly corresponds to the degree of soil contamination, thus demonstrating high bioindicative value. The study confirmed the high relevance of the community approach in metal pollution biomonitoring.

Cladonia lichens as the most effective and essential pioneers in strongly contaminated slag dumps

The epigeic lichen biota of ten post-smelting slag dumps were studied to identify the ecological importance of Cladonia species in spontaneous succession within artificial areas. Species diversity, abundance, constancy and cover indices were determined at the initial stages of vegetation establishment. Substrates under lichen vegetation were characterised in terms of the pH, organic C and total N content, C/N ratio and Zn, Pb, Cd and As concentration. Species occurrence and abundance indices were related to habitat type, enabling the ability to identify species-specific responses to environmental factors. Despite the unfavourable and artificial habitat conditions at dump sites, some Cladonia appear abundant and form swards, with Cladonia rei as a dominant species. They appear to be well-adapted for slag substrate and their special arrangement illustrative of site contamination. Certain sward-forming Cladonia lichens play a fundamental role as effective pioneers in the initial stage of succession and provide stable plant cover development.

Cryptogamic Communities Dominated by the Lichen Cladonia rei — a Case Study of Polish Post-Smelting Dumps in a Worldwide Context

Abstract: Rola, K., Osyczka, P. & Nobis, M. 2014. Cryptogamic communities dominated by the lichen Cladonia rei — a case study of Polish post-smelting dumps in a worldwide context. — Herzogia 27: 121–135. Pioneer vegetation is frequently characterised by a high proportion of cryptogamic species, both in natural sites and anthropogenic and disturbed habitats. This study focuses on pioneer communities developing in strongly affected and contaminated sites of post-smelting dumps in Poland. Lichens, bryophytes and vascular plants were examined in study plots within homogenous patches of vegetation. Phytosociological data on cryptogamic associations, with the lichen Cladonia rei as the predominant species, from anthropogenic habitats of Germany and sand dunes in Ukraine were used for comparative purposes. Hierarchical cluster analysis and non-metric multidimensional scaling (NMDS) were employed to investigate cryptogamic vegetation differentiation and detrended correspondence analysis (DCA) was used to identify the distribution patterns of the individual cryptogamic species. Phytosociological data from Europe were additionally compared with data from Canada representing the Cladonietum nemoxynae by means of NMDS analysis. The results show that the Cladonietum rei is a widespread and well-defined association characteristic for anthropogenic sites in Europe. The Cladonietum rei can occur in several variants; in strongly heavy metal contaminated post-smelting dumps in Poland, the association is characterised by the frequent occurrence of Diploschistes muscorum and Cladonia conista. It creates compact, homogenous patches over relatively large areas and certainly is not a synusium only, but rather a distinct pioneer community.

Phenotypic plasticity of primary thallus in selected Cladonia species (lichenized Ascomycota: Cladoniaceae)

The paper presents the results of comprehensive analyses concerning the phenotypic variability of the primary thallus in five chosen Cladonia species in relation to habitat conditions. Morphology and anatomy, as well as the cortex ultrasculpture, of primary squamules were examined in individual specimens from sunny and shady populations of each species. The Mann-Whitney U test and Principal Component Analysis (PCA) revealed several clear correlations between the type of habitat and the organisation of squamules. Significant differences refer mainly to anatomical features, especially to epinecral layer frequency and cortex thickness. On the contrary, examination of the surface ultrasculpture of squamules under SEM did not show any important differences between populations. Regardless of the habitat factors, a full range of cortical surface rugosity in samples from both habitats was noticed, and a high variability often refers to a singular squamule. The results indicate that some features are largely modified by environmental factors and/or depend on the development stage of individual specimens, and examination of these relationships should be the first step towards the evaluation of the taxonomic usefulness of the considered features.

Different Heavy Metal Accumulation Strategies of Epilithic Lichens Colonising Artificial Post-Smelting Wastes.

Lichens appear to be essential and effective colonisers of bare substrates including the extremely contaminated wastes of slag dumps. This study examines the metal accumulation capacity of epilithic lichens growing directly on the surface of artificial slag sinters. Four species representing different growth forms, i.e., crustose Candelariella aurella, Lecanora muralis, and Lecidea fuscoatra and fruticose Stereocaulon nanodes, were selected to evaluate the relationships between zinc, lead, cadmium, and nickel contents in their thalli and host substrates. Bioaccumulation factors of examined crustose lichens showed their propensity to hyperaccumulate heavy metals. Contrarily, concentrations of metals in fruticose thalli of S. nanodes were, as a rule, lower than in the corresponding substrates. This indicates that the growth form of thalli and degree of thallus adhesion to the substrate has a significant impact on metal concentrations in lichens colonising post-smelting wastes. Nonlinear regression models described by power functions show that at greater levels of Pb concentration in the substrate, the ability of C. aurella, L. muralis and L. fuscoatra to accumulate the metal experiences a relative decrease, whereas hyperbolic function describes a similar trend in relation to Ni content in S. nanodes. This phenomenon may be an important attribute of lichens that facilitates their colonisation of the surface of slag wastes.

Multivariate morphometric analysis of the Stipa turkestanica group (Poaceae: Stipa sect. Stipa)

Based on numerical analyses of macromorphological characters (cluster analysis, principal coordinate analysis and principal component analysis), scanning electron microscopy observation of lemma and lamina micromorphology, as well as field observations, five taxa belonging to the Stipa turkestanica group have been recognized in the mountain area of Central Asia. They are S. turkestanica subsp. turkestanica, S. turkestanica subsp. trichoides, S. macroglossa subsp. macroglossa, S. macroglossa subsp. kazachstanica and S. kirghisorum. As a result of this study, we propose one new combination, S. macroglossa var. pubescens, and designate lectotypes for S. turkestanica subsp. trichoides and S. macroglossa var. pubescens, and an epitype for S. kirghisorum. Illustrations of micromorphological structures of the lemma, patterns of leaf hairiness and an identification key are provided. A taxonomic synopsis including information on nomenclatural types, synonyms, descriptions of the taxa, and, as supplementary information, a list of the specimens examined is also presented.

High intraspecific genetic and morphological variation in the pioneer lichen Cladonia rei colonising slag dumps

This study investigates the genetic and morphological variability of the lichen Cladonia rei inhabiting strongly contaminated postsmelting slag dumps in southern Poland. Altogether, 27 C. rei samples were analysed, including 17 from a single population in one dump. The phylogenetic analysis includes samples of C. rei, outgroup species, and external sequences of Cladonia section representatives from GenBank. Comparative analysis of the internal transcribed spacer (ITS) rDNA sequences revealed the presence of 19 C. rei haplotypes overall, including several of the most frequent, of which 11 are represented by single individuals only. As many as 12 haplotypes were recorded within a single population. Three strongly supported monophyletic clades comprised of specimens from different geographical regions were recovered. Morphometric analysis showed great phenotypic variability within particular clades. Apart from a full range of previously known morphological forms of the species, an additional specific morphotype was recognised in the dumps; however, its representatives do not create a monophyletic group. High genetic variability within a single population suggests that C. rei has a great potential for colonising anthropogenic habitats. This attribute emphasises the role of this lichen as an essential pioneer in the early stages of natural regeneration of such sites.