TY - JOUR
T1 - Annual ryegrass-associated bacteria with potential for plant growth promotion
AU - Castanheira, Nádia
AU - Dourado, Ana Catarina
AU - Alves, Paula Isabel
AU - Cortés-Pallero, Alícia Maria
AU - Delgado-Rodríguez, Ana Isabel
AU - Prazeres, Ângela
AU - Borges, Nuno
AU - Sánchez, Claudia
AU - Goulão Crespo, Maria Teresa Barreto
AU - Fareleira, Paula
N1 - WOS:000340700300015
PY - 2014
Y1 - 2014
N2 - Annual ryegrass is a fast-growing cool-season grass broadly present in the Portuguese "montado", a typically Mediterranean agro-forestry-pastoral ecosystem. A culture-dependent approach was used to investigate natural associations of this crop with potentially beneficial bacteria, aiming to identify strains suitable for biofertilization purposes. Annual ryegrass seedlings were used to trap bacteria from three different soils in laboratory conditions. Using a nitrogen-free microaerophilic medium, 147 isolates were recovered from the rhizosphere, rhizoplane, and surface-sterilized plant tissues, which were assigned to 12 genera in classes Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Bacilli and Actinobacteria. All isolates were able to grow in the absence of nitrogen and several of them were able to perform in vitro activities related to plant growth promotion. Isolates of the genera Sphingomonas and Achromobacter were found to be the most effective stimulators of annual ryegrass growth under nitrogen limitation (47-92% biomass increases). Major enhancements were obtained with isolates G3Dc4 (Achromobacter sp.) and G2Ac10 (Sphingomonas sp.). The latest isolate was also able to increment plant growth in nitrogen-supplemented medium, as well as the phosphate solubilizer and siderophore producer, G1Dc10 (Pseudomonas sp.), and the cellulose/pectin hydrolyser, G3Ac9 (Paenibacillus sp.). This study represents the first survey of annual ryegrass-associated bacteria in the "montado" ecosystem and unveiled a set of strains with potential for use as inoculants.
AB - Annual ryegrass is a fast-growing cool-season grass broadly present in the Portuguese "montado", a typically Mediterranean agro-forestry-pastoral ecosystem. A culture-dependent approach was used to investigate natural associations of this crop with potentially beneficial bacteria, aiming to identify strains suitable for biofertilization purposes. Annual ryegrass seedlings were used to trap bacteria from three different soils in laboratory conditions. Using a nitrogen-free microaerophilic medium, 147 isolates were recovered from the rhizosphere, rhizoplane, and surface-sterilized plant tissues, which were assigned to 12 genera in classes Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Bacilli and Actinobacteria. All isolates were able to grow in the absence of nitrogen and several of them were able to perform in vitro activities related to plant growth promotion. Isolates of the genera Sphingomonas and Achromobacter were found to be the most effective stimulators of annual ryegrass growth under nitrogen limitation (47-92% biomass increases). Major enhancements were obtained with isolates G3Dc4 (Achromobacter sp.) and G2Ac10 (Sphingomonas sp.). The latest isolate was also able to increment plant growth in nitrogen-supplemented medium, as well as the phosphate solubilizer and siderophore producer, G1Dc10 (Pseudomonas sp.), and the cellulose/pectin hydrolyser, G3Ac9 (Paenibacillus sp.). This study represents the first survey of annual ryegrass-associated bacteria in the "montado" ecosystem and unveiled a set of strains with potential for use as inoculants.
KW - Biofertilizers
KW - Nitrogen fixation
KW - Plant growth promoting activities
KW - Plant inoculation
KW - Plant-associated bacteria
UR - http://www.scopus.com/inward/record.url?scp=84904767661&partnerID=8YFLogxK
U2 - 10.1016/j.micres.2013.12.010
DO - 10.1016/j.micres.2013.12.010
M3 - Article
C2 - 24485300
AN - SCOPUS:84904767661
VL - 169
SP - 768
EP - 779
JO - Microbiological Research
JF - Microbiological Research
SN - 0944-5013
IS - 9-10
ER -