+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Revealing the stygobiotic and crenobiotic molluscan biodiversity hotspot in Caucasus: Part I. The phylogeny of stygobiotic Sadlerianinae Szarowska, 2006 (Mollusca, Gastropoda, Hydrobiidae) from Georgia with descriptions of five new genera and twenty-one new species

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          The position of the southwestern Caucasus as a stygobiotic Mollusca hotspot is confirmed. Molecular data of stygobiotic gastropods revealed the diversity of subfamily Sadlerianinae Szarowska, 2006, inhabiting the subterranean environment of Georgia. In addition to the well-known endemic genera Pontohoratia Vinarski, Palatov & Glöer, 2014 and Motsametia Vinarski, Palatov & Glöer, 2014, five more genera were identified in northwestern Georgia as new to the science: Kartvelobia gen. nov., Imeretiopsis gen. nov., Caucasopsis gen. nov., Caucasogeyeria gen. nov., and Hausdorfenia gen. nov. Additionally, 21 new species were found to inhabit the studied area (Samegrelo, Imereti, Racha regions in Georgia).

          Related collections

          Most cited references 43

          • Record: found
          • Abstract: found
          • Article: found
          Is Open Access

          Root Exudation of Primary Metabolites: Mechanisms and Their Roles in Plant Responses to Environmental Stimuli

          Root exudation is an important process determining plant interactions with the soil environment. Many studies have linked this process to soil nutrient mobilization. Yet, it remains unresolved how exudation is controlled and how exactly and under what circumstances plants benefit from exudation. The majority of root exudates including primary metabolites (sugars, amino acids, and organic acids) are believed to be passively lost from the root and used by rhizosphere-dwelling microbes. In this review, we synthetize recent advances in ecology and plant biology to explain and propose mechanisms by which root exudation of primary metabolites is controlled, and what role their exudation plays in plant nutrient acquisition strategies. Specifically, we propose a novel conceptual framework for root exudates. This framework is built upon two main concepts: (1) root exudation of primary metabolites is driven by diffusion, with plants and microbes both modulating concentration gradients and therefore diffusion rates to soil depending on their nutritional status; (2) exuded metabolite concentrations can be sensed at the root tip and signals are translated to modify root architecture. The flux of primary metabolites through root exudation is mostly located at the root tip, where the lack of cell differentiation favors diffusion of metabolites to the soil. We show examples of how the root tip senses concentration changes of exuded metabolites and translates that into signals to modify root growth. Plants can modify the concentration of metabolites either by controlling source/sink processes or by expressing and regulating efflux carriers, therefore challenging the idea of root exudation as a purely unregulated passive process. Through root exudate flux, plants can locally enhance concentrations of many common metabolites, which can serve as sensors and integrators of the plant nutritional status and of the nutrient availability in the surrounding environment. Plant-associated micro-organisms also constitute a strong sink for plant carbon, thereby increasing concentration gradients of metabolites and affecting root exudation. Understanding the mechanisms of and the effects that environmental stimuli have on the magnitude and type of root exudation will ultimately improve our knowledge of processes determining soil CO2 emissions, ecosystem functioning, and how to improve the sustainability of agricultural production.
            • Record: found
            • Abstract: not found
            • Article: not found

            Adapting the IUCN Red List criteria for invertebrates

              • Record: found
              • Abstract: found
              • Article: not found

              Regulation and function of root exudates.

              Root-secreted chemicals mediate multi-partite interactions in the rhizosphere, where plant roots continually respond to and alter their immediate environment. Increasing evidence suggests that root exudates initiate and modulate dialogue between roots and soil microbes. For example, root exudates serve as signals that initiate symbiosis with rhizobia and mycorrhizal fungi. In addition, root exudates maintain and support a highly specific diversity of microbes in the rhizosphere of a given particular plant species, thus suggesting a close evolutionary link. In this review, we focus mainly on compiling the information available on the regulation and mechanisms of root exudation processes, and provide some ideas related to the evolutionary role of root exudates in shaping soil microbial communities.

                Author and article information

                Pensoft Publishers
                05 August 2020
                : 955
                : 1-77
                [1 ] Horná Mičiná 219, 97401, Banská Bystrica, Slovakia
                [2 ] Institute of Zoology, Ilia State University, Kakutsa Cholokashvili Ave 3/5, Tbilisi 0162, Georgia
                [3 ] Department of Malacology, Institute of Zoology and Biomedical Research, Jagiellonian University, ul. Gronostajowa 9, 30-387, Kraków, Poland
                [4 ] Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, al. Mickiewicza 24/28, 30-059, Kraków, Poland
                [5 ] Department of Hydrobiology, Biological Faculty, Moscow State University, 1-12 Leninskie Gory, 119991, Moscow, Russian Federation
                [6 ] Department of Comparative Anatomy, Institute of Zoology and Biomedical Research, Jagiellonian University, ul. Gronostajowa 9, 30-387, Kraków, Poland
                Author notes
                Corresponding author: Artur Osikowski ( a.osikowski@ 123456urk.edu.pl )

                Academic editor: M. Haase

                Jozef Grego, Levan Mumladze, Andrzej Falniowski, Artur Osikowski, Aleksandra Rysiewska, Dmitry M. Palatov, Sebastian Hofman

                This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

                Funded by: Uniwersytet Rolniczy im. Hugona Kołłątaja w Krakowie 100009615 http://doi.org/10.13039/100009615
                Research Article
                Faunistics & Distribution
                Molecular systematics


                Comment on this article