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Abstract: Determining the extent of mycoheterotrophy (MH) in plants, primarily through the use of stable isotope methods, has gained considerable attention in the last decade. The aim of this study [...]

Abstract: Over the last decade, we have witnessed extraordinary progress in the understanding of molecular dialogues between the partners in plant root mutualisms and, as such, a considerable amount of [...]

The genus Drosera (sundews) is represented in British Columbia (BC), Canada, by Drosera rotundifolia (L.), Drosera anglica (Huds.), and their hybrid Drosera x obovata (Mert. & W.D.J. Koch). All three can be found in Sphagnum bogs of central BC, including those within the Aleza Lake Research Forest (ALRF) located 60 km east of Prince George. Vegetation patterns in bogs are known to be correlated with light, water, and nutrient gradients, and despite information being available on the influence of light and water on Drosera occurrence, little information is known about the role of nutrients. Here, we focused on a bog containing all three Drosera species, to determine whether nutrient levels are related to the abundance of the widespread species, D. rotundifolia. Univariate regression tree analysis between soil water chemistry and D. rotundifolia numbers indicates that D. rotundifolia is a calcifuge, preferring moderately acidic soil pH (>5.5) and relatively low calcium levels ( Key words: Drosera rotundifolia, Drosera anglica, calcium, Sphagnum peatlands, carnivorous plants. Le genre Drosera (<>) est represente en Colombie-Britannique (CB), au Canada, par Drosera rotundifolia (L.), Drosera anglica (Huds.) et leur hybride Drosera x obovata (Mert. & W.D.J. Koch). Tous trois peuvent se trouver dans les tourbieres du centre de la CB, incluant les tourbieres de la foret d'enseignement et de recherche d'Aleza Lake situee a 60 km a l'est de Prince George. Les patrons de vegetation des tourbieres sont connus pour etre correles avec les gradients de lumiere, d'eau et de nutriments, et malgre le fait que l'information sur l'influence de la lumiere et de l'eau sur la presence de Drosera soit disponible, le role des nutriments est peu connu. Les auteurs se concentrent ici sur une tourbiere comportant les trois especes de Drosera afin de determiner si les niveaux de nutriments sont relies a l'abondance de l'espece repandue D. rotundifolia. L'analyse d'un arbre de regression multivariable entre la chimie de l'eau du sol et le nombre d'individus indique que D. rotundifolia est un calcifuge, preferant les sols a pH moderement acides (5,5) et a niveaux de calcium relativement faibles ( Mots-cles: Drosera rotundifolia, Drosera anglica, calcium, tourbieres, plantes carnivores., Introduction Members of the sundew genus Drosera represent a number of scientifically important species. Widely known for their carnivorous habit, sundews are key models for ecological processes such as plant [...]

Background:Serpentine ecosystems support different, often unique, plant communities; however, we know little about the soil organisms that associate with these ecosystems. Mycorrhizas, mutualistic symbioses between fungi and roots, are critical to nutrient cycling and energy exchange below ground. Aims:We address three hypotheses: H1, diversity of mycorrhizal fungi in serpentine soils mirrors above-ground plant diversity; H2, the morphology of mycorrhizas and fungi on serpentine soils differs from that on non-serpentine; and H3, mycorrhizal fungal communities of the same or closely related hosts differ between serpentine and non-serpentine soils. Methods:This review focuses on whether plant diversity on serpentine soils correlates with the below ground diversity of mycorrhizal fungi. Results:Studies show that plants and fungi formed abundant ectomycorrhizal and arbuscular mycorrhizal symbioses on and off serpentine soils. No serpentine-endemic fungi were identified. Molecular analyses indicate distinct serpentine isolates forCenococcum geophilumand forAcaulospora, suggesting adaptation to serpentine soils. While fungal sporocarp assemblages on serpentine sites resembled those off serpentine, fruiting of hypogeous fungi was greatly reduced. Conclusions:Ectomycorrhizal fungal communities did not differ between soil types; however, arbuscular mycorrhizal communities differed in some cases but not others. The additive response to multiple factors, described as the serpentine syndrome, may explain part of the response by fungi. [ABSTRACT FROM PUBLISHER]