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The presence of arbuscular mycorrhizal fungi (AMF) is essential for the survival and establishment of most plant species in nature. The reproductive success of invasive plant species in a particular habitat could also depend on these AM fungi. Cinchona pubescens, commonly known as quinine, is highly invasive on Santa Cruz Island, Galápagos, but at the same time severely endangered in its native range on mainland Ecuador due to overexploitation in the past. In this study, we aim at determining the AMF communities associated with C. pubescens at both locations to investigate whether the successful invasion of C. pubescens on Santa Cruz is related to its association with a particular community of AMF. For this, roots of C. pubescens trees were sampled at three sites, one site on Santa Cruz and two sites in the province of Loja, on mainland Ecuador. Communities of AM fungi were determined through the molecular cloning and sequencing of the 18S nrDNA gene and through the delimitation of Operational Taxonomic Units (OTUs), associated with the plant roots. We found 36 AMF OTUs associated with C. pubescens, most of them belonging to the genus Glomus. The highest richness of AMF OTUs was detected in samples from sites located on mainland Ecuador. The AMF communities between Santa Cruz and mainland Ecuador were significantly different, and only five OTUs were shared between both locations. Two dominant OTUs in C. pubescens from Santa Cruz were detected but no dominant OTUs from mainland Ecuador. Almost two thirds of the OTUs associated with C. pubescens had a wide global distribution. Our results suggest that the successful invasion of C. pubescens on Santa Cruz could have been facilitated by local generalist AMF and not by particular AMF. The observed generalist AMF from both locations could be important for conservation plans of restoring the endangered C. pubescens in the native forests on mainland Ecuador. [ABSTRACT FROM AUTHOR]

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Abstract  Biotic interactions affect the impact of potential plant growth promoting microorganisms in the rhizosphere, but their magnitude and fundamentals are often hardly known. In a pot experiment, two physiologically different strains of the ectomycorrhizal fungus Paxillus involutus (GUL and FRA) were tested separately and in combination with associated bacteria (Sphingomonas paucimobilis 1 L, Ralstonia pickettii 16 B, Sphingomonas sp. 23 L) on their effects on the growth of willows (Salix viminalis). Both P. involutus strains significantly increased the growth of the willows compared with non-inoculated plants, but the magnitude of this effect was significantly affected by the fungal strain. The P. involutus strain GUL with higher synthesis of auxin-like substances, acid phosphatases, siderophores and faster utilisation of yeast extract in vitro increased the willow growth in situ more effectively than strain FRA. Additionally, dual inoculation with the P. involutus strains GUL and FRA in combination with the associated bacteria promoted the willow growth, especially the combination with S. paucimobilis 1 L. This bacterial strain used effectively C sources which are common components of plant root exudates, e.g. glucose, sucrose, maltose and mannose as well as compounds synthesized by fungi, e.g. trehalose in vitro. We conclude that the analyses of fungal metabolites and of C source use of associated bacteria can successfully contribute to accelerate the selection of capable plant growth promoting combinations. [ABSTRACT FROM AUTHOR]

From its psychoanalytic beginnings, therapy training has emphasized the crucial role the self of the therapist plays in the effectiveness of therapy. Attention initially focused on therapists' personal history and vulnerabilities and later included an exploration of their relationship style. Less emphasis has been placed on analyzing therapists' belief and meaning systems which inescapably influence their clinical conceptualizations, attitudes, and behaviors. This article defines spirituality as attributions of a personal nature which give meaning to life events, help transcend difficult experiences, maintain hopefulness, and lead to behaviors which honor connectedness and proposes a rationale for including the spiritual dimension in therapy and therapy training and steps graduate training programs and supervisors may take to raise therapists' spiritual understandings. [ABSTRACT FROM AUTHOR]