Rhizosphere bacteria of Costularia spp. from ultramafic soils in New Caledonia: diversity, tolerance to extreme edaphic conditions, and role in plant growth and mineral nutrition

Gonin, M; Gensous, S; Lagrange, A; Ducousso, M; Amir, H; Jourand, P

HERO ID

1838753

Reference Type

Journal Article

Year

2013

Language

English

PMID

23540334

HERO ID 1838753
In Press No
Year 2013
Title Rhizosphere bacteria of Costularia spp. from ultramafic soils in New Caledonia: diversity, tolerance to extreme edaphic conditions, and role in plant growth and mineral nutrition
Authors Gonin, M; Gensous, S; Lagrange, A; Ducousso, M; Amir, H; Jourand, P
Journal Canadian Journal of Microbiology
Volume 59
Issue 3
Page Numbers 164-174
Abstract Rhizosphere bacteria were isolated from Costularia spp., pioneer sedges from ultramafic soils in New Caledonia, which is a hotspot of biodiversity in the South Pacific. Genus identification, ability to tolerate edaphic constraints, and plant-growth-promoting (PGP) properties were analysed. We found that 10(5) colony-forming units per gram of root were dominated by Proteobacteria (69%) and comprised 21 genera, including Burkholderia (28%), Curtobacterium (15%), Bradyrhizobium (9%), Sphingomonas (8%), Rhizobium (7%), and Bacillus (5%). High proportions of bacteria tolerated many elements of the extreme edaphic conditions: 82% tolerated 100 μmol·L(-1) chromium, 70% 1 mmol·L(-1) nickel, 63% 10 mmol·L(-1) manganese, 24% 1 mmol·L(-1) cobalt, and 42% an unbalanced calcium/magnesium ratio (1/16). These strains also exhibited multiple PGP properties, including the ability to produce ammonia (65%), indole-3-acetic acid (60%), siderophores (52%), and 1-aminocyclopropane-1-carboxylate (ACC) deaminase (39%); as well as the capacity to solubilize phosphates (19%). The best-performing strains were inoculated with Sorghum sp. grown on ultramafic substrate. Three strains significantly enhanced the shoot biomass by up to 33%. The most successful strains influenced plant nutrition through the mobilization of metals in roots and a reduction of metal transfer to shoots. These results suggest a key role of these bacteria in plant growth, nutrition, and adaptation to the ultramafic constraints.
Doi 10.1139/cjm-2012-0570
Pmid 23540334
Wosid WOS:000316938300004
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000316938300004
Is Public Yes
Language Text English
Keyword Costularia; rhizospheric bacteria; New Caledonia; ultramafic soils