P Loján1,2, M Demortier1, S L S Velivelli3, S Pfeiffer4, J P Suárez2, P de Vos5, B D Prestwich3, A Sessitsch4, S Declerck1. 1. Earth and Life Institute, Applied Microbiology, Mycology, Université catholique de Louvain Croix du Sud, Louvain-la-Neuve, Belgium. 2. Departamento de Ciencias Naturales, Universidad Técnica Particular de Loja, Loja, Ecuador. 3. School of Biological, Earth and Environmental Sciences, University College Cork, Cork, Ireland. 4. Bioresources Unit, Department of Health and Environment, AIT Austrian Institute of Technology GmbH, Tulln, Austria. 5. Laboratory for Microbiology, University of Gent, Gent, Belgium.
Abstract
AIMS: This study aimed at evaluating the impact of seven plant growth-promoting rhizobacteria (PGPR) on root colonization and life cycle of Rhizophagus irregularis MUCL 41833 when co-entrapped in alginate beads. METHODS AND RESULTS: Two in vitro experiments were conducted. The first consisted of the immobilization of R. irregularis and seven PGPR isolates into alginate beads to assess the effect of the bacteria on the pre-symbiotic growth of the fungus. In the second experiment, the best performing PGPR from experiment 1 was tested for its ability to promote the symbiotic development of the AMF in potato plantlets from three cultivars. Results showed that only one isolate identified as Pseudomonas plecoglossicida (R-67094) promoted germ tube elongation and hyphal branching of germinated spores during the pre-symbiotic phase of the fungus. This PGPR further promoted the symbiotic development of the AMF in potato plants. CONCLUSIONS: The co-entrapment of Ps. plecoglossicida R-67094 and R. irregularis MUCL 41833 in alginate beads improved root colonization by the AMF and its further life cycle under the experimental conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Co-entrapment of suitable AMF-PGPR combinations within alginate beads may represent an innovative technology that can be fine-tuned for the development of efficient consortia-based bioformulations.
AIMS: This study aimed at evaluating the impact of seven plant growth-promoting rhizobacteria (PGPR) on root colonization and life cycle of Rhizophagus irregularis MUCL 41833 when co-entrapped in alginate beads. METHODS AND RESULTS: Two in vitro experiments were conducted. The first consisted of the immobilization of R. irregularis and seven PGPR isolates into alginate beads to assess the effect of the bacteria on the pre-symbiotic growth of the fungus. In the second experiment, the best performing PGPR from experiment 1 was tested for its ability to promote the symbiotic development of the AMF in potato plantlets from three cultivars. Results showed that only one isolate identified as Pseudomonas plecoglossicida (R-67094) promoted germ tube elongation and hyphal branching of germinated spores during the pre-symbiotic phase of the fungus. This PGPR further promoted the symbiotic development of the AMF in potato plants. CONCLUSIONS: The co-entrapment of Ps. plecoglossicida R-67094 and R. irregularis MUCL 41833 in alginate beads improved root colonization by the AMF and its further life cycle under the experimental conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Co-entrapment of suitable AMF-PGPR combinations within alginate beads may represent an innovative technology that can be fine-tuned for the development of efficient consortia-based bioformulations.
Authors: Omri M Finkel; Gabriel Castrillo; Sur Herrera Paredes; Isai Salas González; Jeffery L Dangl Journal: Curr Opin Plant Biol Date: 2017-06-13 Impact factor: 7.834