Isotope ratio mass spectrometry identifies soil microbial biocontrol agents having trophic relations with the plant pathogen Armillaria mellea |
| |
| Institution: | 1. Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010 S. Michele all’Adige, Italy;2. Department of environmental system (D-USYS), Plant Pathology group, Institute of Integrative Biology (IBZ), Swiss Federal Institute of Technology, Universitätstrasse 2, 8092 Zurich, Switzerland;3. Laboratory of Mycology, Department of Earth Science and Environment, University of Pavia, via S. Epifanio 14, 27100 Pavia, Italy;1. Instituto de Tecnologia Química e Biológica, Av. da República – EAN, 2780-157 Oeiras, Portugal;2. Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal;3. CIFC-Biotrop/IICT – Instituto de Investigação Científica Tropical, Quinta do Marquês, 2784-505 Oeiras, Portugal;4. Instituto Nacional de Investigação Agrária e Veterinária IP, Quinta do Marquês, Av. da República, 2780-159 Oeiras, Portugal;1. Soil Ecology Research Group, Graduate School of Environment and Information Sciences, Yokohama National University, 79-7 Tokiwadai, Yokohama 240-8501, Japan;2. Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji, Tokyo 192-0397, Japan;1. Institute of Socio-Arts and Sciences, Tokushima University, 1-1 Minamijosanjima-cho, Tokushima 770-8502, Japan;2. Tokushima Agriculture, Forestry, and Fisheries Technology Support Center, 1660 Ishii-aza-Ishii, Ishii-cho, Nanishi-gun, Tokushima 779-3233, Japan;3. Faculty of Bioenvironmental Science, Kyoto Gakuen University, 1-1 Nanjo-Ohtani, Sogabe-cho, Kameoka, 621-8555, Japan;1. Research Institute for Production Development, Shimogamo-morimotocho, Sakyo-ku, Kyoto 606-0805, Japan;2. Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308, Suematsu, Nonoichi, Ishikawa 921-8836, Japan;3. Department of Complementary and Alternative Medicine, Clinical R&D, Graduate School of Medical Science, Kanazawa University, 13-1, Takara-machi, Kanazawa 920-8640, Japan;1. British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK;2. Polish Academy of Sciences, Institute of Botany, Bryology Laboratory, UI Lubicz 46, PL-31512 Krakow, Poland;3. Charles University Prague, Department of Botany, Faculty of Science, Benátská 2, CZ-128 01 Prague 2, Czech Republic;1. Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175 CNRS, 1919 route de Mende, 34293 Montpellier cedex 5, France;2. Technische Universität Braunschweig (TUB), Institut für Geoökologie, Langer Kamp 19c, D-38106 Braunschweig, Germany;3. Luxembourg Institute of Science and Technology, Department Environmental Research and Innovation, 41, rue du Brill, L-4422 Belvaux, Luxembourg;4. Institut Universitaire de France, France;5. Centre IRD Ile de France, IEES Université Pierre et Marie Curie (Paris 6) 7618, 32 rue Henri Varagnat, 93143 BONDY Cedex, France |
| |
| Abstract: | An understanding of the types of interactions that take place between plant pathogens and other microorganisms in the natural environment is crucial in order to identify new potential biocontrol agents. The use of microorganisms labelled with stable isotopes is a potentially useful method for studying direct parasitisation of a given pathogen or assimilation of the pathogen's metabolites by microorganisms. A microorganism labelled with a stable isotope can be monitored in the environment and isotope ratio mass spectrometry can detect whether it is directly parasitised or its metabolites are used by other microorganisms. In this study, we isolated 158 different species of fungi and bacteria from soil and assayed their biocontrol potential against a plant pathogen (Armillaria mellea) by coupling a dual-culture test with mass spectrometry analysis of the 13C isotope in the microorganisms in presence of 13C-labelled A. mellea. The microorganisms affected the pathogen by means of antibiosis phenomena (total or partial inhibition of pathogen growth, alteration of its morphology) and by antagonism, probably resulting from competition for space and nutrients or from mycoparasitism. Isotope ratio mass spectrometry was used to identify direct trophic interactions between microorganisms and the pathogen as in dual cultures as in soil microcosms. Six fungi and one bacterium were found to display the best active trophic behaviour against the pathogenin dual cultures; three microorganisms were discarded due to their plant pathogen potential. Trichoderma harzianum, Pseudomonas fluorescens and Rhodosporidium babjevae were selected to carry out the experiments. T. harzianum inhibited pathogen development (rate of inhibition 80 ± 0.19%) and its δ 13C values increased (244.03 ± 36.70‰) in contact with 13C-labelled A. mellea. Lower levels of antagonism and correspondingly lower assimilation of 13C were detected in P. fluorescens and R. babjevae. Only T. harzianum maintained mycoparasitic activity in the soil microcosm, showing a δ 13C value of 1.97 ± 2.24‰ after one month in co-presence with the labelled pathogen. This study provides support for the use of isotope ratio mass spectrometry as an additional tool in screening for potential biocontrol agents. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
