Theme 5-2: Drought Management and Climate Change--Poster Sessions
Description
The functional attributes of the microbiome associated with timothy for growth promotion properties, antimicrobial and biosurfactant capacities were characterized. A total of 254 culturable bacteria were identified by 16S rRNA sequencing and grouped into 16 taxa that shared high homology of 98–99% with other known sequences. The majority of bacterial isolates exhibited multifunctional growth promotion attributes and plant stress improvement. The selection of competent and compatible strains for application in forage production is dependent on the recognition of root exudates and motility towards the roots, attachment to the root surface, formation of biofilm, penetration, and colonization of internal tissues. We selected competent rhizospheric bacteria to generate a multispecies consortium made of three strains that displayed growth-promoting abilities in timothy through the production of IAA, volatile organic compounds that increased root biomass, the production of siderophores and antibiotic resistance, as well as the ability to colonize plants. This study demonstrated that the multispecies consortium displayed biofilm formation and chemotactic behaviour towards several organic acids and towards root exudates released from the model grass Brachypodium distachyon. Organic acids were successful in stimulating the formation of biofilm of the multispecies consortium. In particular, fumaric and malic acids enhanced selective recruitment of the multispecies consortium in a dose-dependent manner thereby, promoting biofilm formation on root surface as demonstrated in SEM micrographs. The multispecies consortium exhibited biofilm-related traits including the production of exopolysaccharides (EPS) and alginate. EPS amounts were comparable in single strains and consortium forms and alginate production increased by 160% when the consortium was subjected to drought stress. These findings demonstrated that plant-microbe interaction is the hub of various factors directly affecting this balanced dual relation and that root exudates could be very selective in recruiting highly qualified multispecies consortium.
Citation
Saleh, Dina; Jabaji, Suha; and Seguin, Philippe, "Microbiome of the Cool Season Forage Grass Timothy (Phleum pratense L.) and Its Potential Role in Stress Tolerance" (2022). IGC Proceedings (1993-2023). 10.
https://uknowledge.uky.edu/igc/24/5-2/10
Included in
Microbiome of the Cool Season Forage Grass Timothy (Phleum pratense L.) and Its Potential Role in Stress Tolerance
The functional attributes of the microbiome associated with timothy for growth promotion properties, antimicrobial and biosurfactant capacities were characterized. A total of 254 culturable bacteria were identified by 16S rRNA sequencing and grouped into 16 taxa that shared high homology of 98–99% with other known sequences. The majority of bacterial isolates exhibited multifunctional growth promotion attributes and plant stress improvement. The selection of competent and compatible strains for application in forage production is dependent on the recognition of root exudates and motility towards the roots, attachment to the root surface, formation of biofilm, penetration, and colonization of internal tissues. We selected competent rhizospheric bacteria to generate a multispecies consortium made of three strains that displayed growth-promoting abilities in timothy through the production of IAA, volatile organic compounds that increased root biomass, the production of siderophores and antibiotic resistance, as well as the ability to colonize plants. This study demonstrated that the multispecies consortium displayed biofilm formation and chemotactic behaviour towards several organic acids and towards root exudates released from the model grass Brachypodium distachyon. Organic acids were successful in stimulating the formation of biofilm of the multispecies consortium. In particular, fumaric and malic acids enhanced selective recruitment of the multispecies consortium in a dose-dependent manner thereby, promoting biofilm formation on root surface as demonstrated in SEM micrographs. The multispecies consortium exhibited biofilm-related traits including the production of exopolysaccharides (EPS) and alginate. EPS amounts were comparable in single strains and consortium forms and alginate production increased by 160% when the consortium was subjected to drought stress. These findings demonstrated that plant-microbe interaction is the hub of various factors directly affecting this balanced dual relation and that root exudates could be very selective in recruiting highly qualified multispecies consortium.
