24 research outputs found
Motility and biofilm production involved in the interaction of phosphate solubilizing endophytic strains with peanut, maize and soybean plants
Endophytic plant growth promoting bacteria are of great interest since the ability to colonize the internal tissues of plants gives it an adaptive advantage. To confer any beneficial effect on the plant, bacteria must present a successful colonization and thus be competent in the rhizosphere and finally infect internal tissues. In this sense, bacterial motility is an essential property involved in plant-microorganism interaction where bacteria can colonize the root and at the same time form biofilms. Within plant beneficial bacteria those that present phosphate solubilizing activity are of great interest due to the contribution of phosphorus to plants. The objective of this work was to evaluate the motility and biofilm formation properties of the strains Serratia sp. S119 and Enterobacter sp. J49 growing in the presence of peanut, maize and soybean root exudates. Results obtained indicated that both strains have flagella, possess swimming, swarming and twitching motilities and showed differential chemotactic attraction against root exudates. In addition, the strains under study showed the ability to form biofilms, being this ability greater in minimal media, in which a greater decrease was also seen by the addition of root exudates in the first hours of growth. The changes produced by the addition of root exudates in the chemotaxis and biofilm formation of the strains suggests that compounds released by the plants are detected by these bacteria and could be part of the molecular dialogue involved in their interaction with the roots of plant.Fil: Lucero, Cinthia Tamara. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica; ArgentinaFil: Lorda, Graciela Susana. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica; ArgentinaFil: Ludueña, Liliana Mercedes. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Anzuay, MarĂa Soledad. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Taurian, Tania. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; Argentin
Peanut Endophytic Phosphate Solubilizing Bacteria Increase Growth and P Content of Soybean and Maize Plants
Phosphorus (P) is a limiting factor of plant development due to its low availability in the soil. The use of endophytic phosphate solubilizing bacteria as a more sustainable alternative to the use of chemical phosphorus fertilizers is proposed in this study. The objectives were to analyze the effect of simple inoculations of native peanut endophytic phosphate solubilizing bacteria on plant growth promotion and P content of soybean and maize and to evaluate their survival and endophytic colonization capacity on these plants. In addition, bacterial plant cell wall degrading enzymes activities in presence or absence of root exudates was determined. Soybean, maize and peanut plants were grown on a microcosm scale and inoculated with Enterobacter sp. J49 or Serratia sp. S119. It was observed that phosphate solubilizing strains promoted the growth of maize and soybean plants and contributed significantly P to their tissues. A significant increase in the phosphate solubilizing capacity of the plant rhizosphere after the end of the assay was observed. The strains showed to survive in plant’s growth substrate and in the case of Enterobacter sp. J49, it showed also to colonize endophytically maize and soybean. Root exudates of the three plants showed to produce changes in pectinase and cellulase activities of the strains. The bacterial strains analyzed in this study constitutes potential sources for the formulation of biofertilizers for their application for several crops in agricultural soils with low P content.Fil: Lucero, Cinthia Tamara. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de La Pampa; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Lorda, Graciela Susana. Universidad Nacional de La Pampa; ArgentinaFil: Anzuay, MarĂa Soledad. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de Ciencias Naturales; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas. - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Ludueña, Liliana Mercedes. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de Ciencias Naturales; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas. - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Taurian, Tania. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas. - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FisicoquĂmicas y Naturales. Departamento de Ciencias Naturales; Argentin
Native bacteria isolated from roots and rhizosphere of Solanum lycopersicum L. increase tomato seedling growth under a reduced fertilization regime
In semiarid regions is important to use native strains best adapted to these environments to optimize plant-PGPR interaction. We aimed to isolate and characterize PGPR from roots and rhizosphere of a tomato crop, as well as studying the effect of its inoculation on tomato seedlings growth. We selected four strains considering their effectiveness of fixing nitrogen, solubilizing phosphate, producing siderophores and indole acetic acid. They belong to the genera Enterobacter, Pseudomonas, Cellulosimicrobium, and Ochrobactrum. In addition, we also analyzed the ability to solubilize Ca3(PO4)2, FePO4 and AlPO4 and the presence of one of the genes encoding the cofactor PQQ in their genome. Enterobacter 64S1 and Pseudomonas 42P4 showed the highest phosphorus solubilizing activity and presence of pqqE gene. Furthermore, in a tomato-based bioassay in speed-bed demonstrated that a sole inoculation at seedling stage with the strains increased dry weight of roots (49–88%) and shoots (39–55%), stem height (8–13%) and diameter (5–8%) and leaf area (22–31%) and were equal or even higher than fertilization treatment. Leaf nitrogen and chlorophyll levels were also increased (50–80% and 26–33%) compared to control. These results suggest that Enterobacter 64S1 and Pseudomonas 42P4 can be used as bio-inoculant in order to realize a nutrient integrated management.Fil: PĂ©rez Rodriguez, MarĂa Micaela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto de BiologĂa AgrĂcola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de BiologĂa AgrĂcola de Mendoza; ArgentinaFil: Piccoli, Patricia NoemĂ. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto de BiologĂa AgrĂcola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de BiologĂa AgrĂcola de Mendoza; ArgentinaFil: Anzuay, MarĂa Soledad. Universidad Nacional de RĂo Cuarto; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Baraldi, Rita. Consiglio Nazionale delle Ricerche; ItaliaFil: Neri, Luisa. Consiglio Nazionale delle Ricerche; ItaliaFil: Taurian, Tania. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de RĂo Cuarto; ArgentinaFil: Lobato Ureche, Miguel AndrĂ©s. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto de BiologĂa AgrĂcola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de BiologĂa AgrĂcola de Mendoza; ArgentinaFil: Segura, Diana MarĂa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto de BiologĂa AgrĂcola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de BiologĂa AgrĂcola de Mendoza; ArgentinaFil: Cohen, Ana Carmen. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto de BiologĂa AgrĂcola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de BiologĂa AgrĂcola de Mendoza; Argentin
Development and field evaluation of liquid inoculants with native Bradyrhizobial strains for peanut production
A critical process in the leguminous crops cycles is biological nitrogen fixation (BNF). Application of inoculants with N fixing bacteria is economically and environmentally favourable. The aim of this work was to select competitive native peanut microsymbionts, evaluate their survival in inoculant support and assess their impact on peanut (Arachis hypogaea L.) production under field conditions at CĂłrdoba province in Argentina. The efficient N fixing Bradyrhizobium sp. J-81 and Bradyrhizobium sp. J-237, previously obtained from peanut nodules in the region of Cordoba, Argentina, were evaluated. In microcosm assays, plants inoculated with these isolates demonstrated better symbiotic parameters than those inoculated with reference strains. Different bacterial growth media and inoculant stabiliser solutions were evaluated. Balanced medium and arabic gum stabilising solution had optimal bacterial growth and the highest bacterial concentration and viability, respectively. Inoculation with either inoculants resulted in 44% greater peanut pod yield at Pizarro compared to the non-inoculated plants, although no significant differences were found with respect to commercial inoculants treatments.La fixation biologique de l’Azote (FBA) est un processus important dans le cycle de vie des lĂ©gumineuses. L’application d’inoculum de bactĂ©ries fixatrices d’azote est favorable au double plan Ă©conomique et environnemental. Le but de cette Ă©tude Ă©tait de sĂ©lectionner des bactĂ©ries symbiotiques de l’arachide natives et compĂ©titives, Ă©valuer leur temps de survie dans support d’inoculum et Ă©valuer leur impact sur la production en plein champ de l’arachide (Arachis hypogaea L.) dans la province de CĂłrdoba en Argentine. Les bactĂ©ries fixatrices d’azote Bradyrhizobium sp. J-81 et Bradyrhizobium sp. J-237, extraites de nodules collectĂ©s sur des plants cultivĂ©s dans la rĂ©gion de Cordoba en Argentina, ont Ă©tĂ© Ă©valuĂ©es. Dans des essais de microcosme, des plants inoculĂ©s avec ces isolats ont exhibĂ©s de meilleurs paramètres symbiotiques que les plants non inoculĂ©s. DiffĂ©rents mĂ©dia de culture bactĂ©rienne et supports inoculums ont Ă©tĂ© testĂ©s. Medium mixte et solution stabilisĂ©e Ă la gomme arabique ont respectivement exhibĂ©s la croissance optimale des bactĂ©ries et la meilleure conservation et viabilitĂ© des bactĂ©ries. L’application de n’importe quel inoculum produisit 44% plus de rendement en gousses d’arachides Ă Pizarro par rapport aux plantes non-inoculĂ©es, et ceci bien qu’aucune diffĂ©rence significative n’a Ă©tĂ© observĂ©e en comparaison avec les traitements Ă l’inoculum du commerce.Fil: Valetti, Lucio. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; ArgentinaFil: Angelini, Jorge Guillermo. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; ArgentinaFil: Taurian, Tania. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; ArgentinaFil: Ibañez, Fernando Julio. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; ArgentinaFil: Muñoz, Vanina Laura. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; ArgentinaFil: Anzuay, MarĂa Soledad. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; ArgentinaFil: Ludueña, Liliana Mercedes. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; ArgentinaFil: Fabra, Adriana Isidora. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentin
Role of bacterial pyrroloquinoline quinone in phosphate solubilizing ability and in plant growth promotion on strain <i>Serratia</i> sp. S119
The aim of this study was to analyze if cofactor pyrroquinoline quinone from Serratia sp. S119 is involved in the inorganic phosphate solubilization mechanism and in its ability to promote the plant growth. Site directed mutagenesis was performed to obtain a pqqE- minus mutant of strain Serratia sp. S119. The phosphate solubilization ability, gluconate and PQQ production of the mutant Serratia sp. RSL (pqqE-) was analyzed. Mutant RSL (pqqE-) showed significant decrease in P soluble and gluconic acid levels produced and undetectable levels of PQQ cofactor compared with wild-type strain. Complementation with synthetic PQQ cofactor restored P solubilization and gluconate production reaching the levels produced by wild-type strain. PqqE gene sequence indicated that it is highly conserved within Serratia strains and its product shows conserved motifs found in other PqqE proteins of several bacteria. The effect of the inoculation of the PQQ- mutant on peanut and maize plants was evaluated in pot assays. Plants growth parameters showed no differences among the different treatments indicating that PQQ from Serratia sp. S119 is not involved in the growth promotion of these plants. PQQ cofactor is essential for phosphate solubilization ability of Serratia sp. S119 but is not required for growth promotion of peanut and maize plants.Facultad de Ciencias ExactasCentro de InvestigaciĂłn y Desarrollo en Fermentaciones Industriale
Beneficial effects of native phosphate solubilizing bacteria on peanut (Arachis hypogaea L) growth and phosphorus acquisition
This study analyses the effect of inoculation of native phosphate solubilizing bacteria on peanut (Arachis hypogaea L.) growth and phosphorus acquisition. Peanut plants were inoculated individually with 18 native phosphate solubilizing bacteria in microcosm studies using a low content P soil from the producing area. Survival of inoculated bacteria in soil at the end of the experiment was determined by streaking serial dilutions of dry soil samples and subsequent rep-fingering analysis of the colonies. The ability of peanut plants to increase P levels without bacteria was determined in hydroponic culture. The results obtained indicated that inoculation of native phosphate solubilizing bacteria on peanut seedlings led to an increase in at least one of the plant growth parameters analyzed. The beneficial effect of bacteria inoculation was mainly observed in aerial organs of peanut plants. Inoculation of Serratia sp. J260, Enterobacter sp. J33, Acinetobacter sp. L176, Enterococcus sp. L185, Enterococcus sp. L191 and Bacillus sp. L55 on peanut plants led to an increase in plant or soil P content. Plant assay in hydroponic conditions indicated that peanut plants growing with tricalcium phosphate were able to release soluble P into the growth medium reaching values similar to those of plants growing with available P. The beneficial effects of the bacteria analyzed in this study and their ability to survive encourage us to consider them for the production of a potential P-bioinoculant for peanut crops.Fil: Anzuay, MarĂa Soledad. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales; ArgentinaFil: Ludueña, Liliana Mercedes. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales; ArgentinaFil: Angelini, Jorge Guillermo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales; ArgentinaFil: Fabra, Adriana Isidora. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales; ArgentinaFil: Taurian, Tania. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales; Argentin
Genetic diversity of phosphate-solubilizing peanut (Arachis hypogaea L.) associated bacteria and mechanisms involved in this ability
In this study, attempts were made to analyze mechanisms involved in the bacterial phosphate-solubilizing ability of peanut isolates. Bacteria were taxonomically identified by analysis of 16S rDNA sequence. Levels of soluble P released by the isolates in unbuffered or buffered with Tris–HCl or MES NBRIP-BPB medium as well as the production of D-gluconic acid were determined in their culture. Presence of two of the genes encoding the cofactor PQQ of GDH enzyme was analyzed in the genome of this bacterial collection. 16S rDNA sequence analysis indicated that isolates belong to genera Serratia, Enterobacter, Pantoea, Acinetobacter, Bacillus and Enterococcus. All bacteria showed ability to solubilize tricalcium phosphate either in unbuffered or buffered medium. Nevertheless, addition of buffer solutions reduced levels of Pi liberated by the isolates. Although almost all isolates produced detectable amounts of D-gluconic acid, no correlation with levels of P soluble released were observed. The presence of pqqE and pqqC genes was detected only in Gram negative bacteria. It was concluded from this study that the mechanism involved in phosphate solubilization is organic acids production and, presence of pqq genes in all Gram negative bacteria analyzed encourages to confirm their role in bacterial phosphate solubilizing ability as well to identify genes involved in this PGP trait in Gram positive bacteria.Fil: Anzuay, MarĂa Soledad. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Frola, Ornella. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; ArgentinaFil: Angelini, Jorge Guillermo. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Ludueña, Liliana Mercedes. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Fabra, Adriana Isidora. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Taurian, Tania. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Plant beneficial rhizobacteria community structure changes through developmental stages of peanut and maize
Our objective in this study was to analyze the structure of the rhizobacterial community during different growth stages of peanut and maize plants. Microcosm assays were performed using pots containing unsterile soil from the peanut growing area of Argentina in which peanut and maize plants were grown during 120 and 100 days, respectively. Four to five samples of rhizospheric soil were obtained at the beginning of the assay, at an early growth stage of each plant and at the end of the assay. Two replicate DNA extractions from rhizospheric soil samples were realized per treatment on both microcosm assays to analyze rhizobacterial community structure by high-throughput sequencing of 16S rRNA gene.
We observed changes in rhizobacteria community structure with crop developmental stages. Community structure changes occurred at several bacteria taxonomic levels, and major changes were observed in later stages. In particular, plant growth promoting bacteria genera were promoted in later stages. Our results indicate plant rhizospheric selection for growth enhancing rhizobacteria during stages of high nutrient demand. In conclusion, the structure of the rhizobacterial communities of peanut and maize are influenced by plant phenological stages, and beneficial bacteria are favoured in late phenological stages.Instituto de BiotecnologĂaFil: Anzuay, MarĂa Soledad. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FĂsico-QuĂmicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Anzuay, MarĂa Soledad. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Pin Viso, Natalia Daniela. Instituto Nacional de TecnologĂa Agropecuaria (INTA). Instituto de AgrobiotecnologĂa y BiologĂa Molecular; ArgentinaFil: Pin Viso, Natalia Daniela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Ludueña, Liliana Mercedes. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FĂsico-QuĂmicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Ludueña, Liliana Mercedes. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Morla, Federico Daniel. Universidad Nacional de RĂo Cuarto. Facultad de AgronomĂa y Veterinaria. Departamento de ProducciĂłn Vegetal; ArgentinaFil: Angelini, Jorge Guillermo. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FĂsico-QuĂmicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Angelini, Jorge Guillermo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Taurian, Tania. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas, FĂsico-QuĂmicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Taurian, Tania. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Investigaciones AgrobiotecnolĂłgicas; Argentin
First insights into the role of PQQ cofactor in the modulation of bacterial redox state and in the early interaction with peanut (Arachis hypogaea L.)
The objective of this work was to study the role of pyrroloquinolinequinone (PQQ) of Serratia sp. S119 strain in the maintenance of the bacterial redox state and in the early interaction with peanut. Lipid peroxidation and antioxidant enzymatic activities were analyzed in Serratia sp. S119 and in its PQQ minus mutant Serratia sp. RSL, exposed to hydrogen peroxide (H2O2). In the plant-bacteria interaction histochemical detection and quantification of H2O2 content was determined in peanut roots inoculated with the strains. The response to the oxidant agent showed significant differences between both studied bacteria. RSL showed growth decrease, lipid peroxidation increase and catalase enzyme activity reduction when the strain was exposed to H2O2. Also, a decrease in peroxidase activity was observed, regardless the presence or absence of this reactive species in this strain. The histochemical staining and quantification of ROS in peanut roots indicated an increase of H2O2 at 60 and 240 min postinoculation (pI) when plants were inoculated with RSL and S119 strains, respectively. In conclusion, PQQ would participate in the maintenance of cellular redox balance during oxidative stress in Serratia sp. S119 and, in the early recognition steps between this strain and peanut plant.Fil: Ludueña, Liliana Mercedes. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Bianucci, Eliana Carolina. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Anzuay, MarĂa Soledad. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Angelini, Jorge Guillermo. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Fabra, Adriana Isidora. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; ArgentinaFil: Taurian, Tania. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂmicas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; Argentin
Interrelationships between Bacillus sp. CHEP5 and Bradyrhizobium sp. SEMIA6144 in the induced systemic resistance against Sclerotium rolfsii and symbiosis on peanut plants
Plant-growth-promoting bacteria are often used to enhance crop yield and for biological control of phytopathogens. Bacillus sp. CHEP5 is a biocontrol agent that induces systemic resistance (ISR) in Arachis hypogaea L. (peanut) against Sclerotium rolfsii, the causal agent of root and stem wilt. In this work, the effect of the co-inoculation of Bacillus sp. CHEP5 and the peanut nodulating strain Bradyrhizobium sp. SEMIA 6144 was studied on induction of both systemic resistance and nodulation processes. Bradyrhizobium sp. SEMIA 6144 did not affect the ability of Bacillus sp. CHEP5 to protect peanut plants from S. rolfsii by ISR and the priming in challenged-plants, as evidenced by an increment in phenylalanine ammonia-lyase enzyme activity. Additionally, the capacity of Bradyrhizobium sp. SEMIA 6144 to induce nodule formation in pathogen-challenged plants was improved by the presence of Bacillus sp. CHEP5.Fil: Figueredo, MarĂa Soledad. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Tonelli, Maria Laura. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Taurian, Tania. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Angelini, Jorge Guillermo. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Ibañez, Fernando Julio. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Valetti, Lucio. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Muñoz, Vanina Laura. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Anzuay, MarĂa Soledad. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Ludueña, Liliana Mercedes. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Fabra, Adriana Isidora. Universidad Nacional de RĂo Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Biologia General; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin