Papers by Fernando Ibáñez
El retorno del avetoro a Doñana: hallados nuevos nidos en 2003 y 2004
Quercus, 2004
Journal of applied microbiology, 2015
We evaluated whether reactive oxygen species (ROS) production and the plant antioxidant system ar... more We evaluated whether reactive oxygen species (ROS) production and the plant antioxidant system are involved in the symbiotic interaction between bradyrhizobia and legumes infected by crack entry, without intracellular infection threads (IT) formation, such as Arachis hypogaea L. (peanut). The role of bradyrhizobial Nod factors (NF) in modulating the plants' oxidative burst was also analysed. Histochemical and quantitative procedures were used to detect ROS levels in inoculated and in NF-treated peanut roots. Increase in root H2O2 production was determined at 10 min postinoculation with Bradyrhizobium sp. SEMIA 6144 or after NF addition. ROS production was modulated by NF. From 15 to 30 min postinoculation, the compatibility of Bradyrhizobium sp.-peanut interaction depends mostly on the H2O2 detoxification via catalase. We demonstrated for the first time that the early events of the symbiotic interaction in legumes invaded by crack entry trigger an increase in ROS production (rep...
Sequence and expression analysis of putative Arachis hypogaea (peanut) Nod factor perception proteins
Journal of Plant Research, 2015
Peanut, like most legumes, develops a symbiotic relationship with rhizobia to overcome nitrogen l... more Peanut, like most legumes, develops a symbiotic relationship with rhizobia to overcome nitrogen limitation. Rhizobial infection of peanut roots occurs through a primitive and poorly characterized intercellular mechanism. Knowledge of the molecular determinants of this symbiotic interaction is scarce, and little is known about the molecules implicated in the recognition of the symbionts. Here, we identify the LysM extracellular domain sequences of two putative peanut Nod factor receptors, named AhNFR1 and AhNFP. Phylogenetic analyses indicated that they correspond to LjNFR1 and LjNFR5 homologs, respectively. Transcriptional analysis revealed that, unlike LjNFR5, AhNFP expression was not induced at 8 h post bradyrhizobial inoculation. Further examination of AhNFP showed that the predicted protein sequence is identical to GmNFR5 in two positions that are crucial for Nod factor perception in other legumes. Analysis of the AhNFP LysM2 tridimensional model revealed that these two amino acids are very close, delimiting a zone of the molecule essential for Nod factor recognition. These data, together with the analysis of the molecular structure of Nod factors of native peanut symbionts previously reported, suggest that peanut and soybean could share some of the determinants involved in the signalling cascade that allows symbiosis establishment.
Applied Soil Ecology, 2014
The term "Plant Growth Promoting Bacteria" or PGPB designates a diverse group of prokaryotic micr... more The term "Plant Growth Promoting Bacteria" or PGPB designates a diverse group of prokaryotic microorganisms that can increase plant growth by diverse mechanisms. Some PGPB are capable of colonizing root inner tissues and constitute endophytic populations. Incorporation of these microorganisms into agricultural practices may constitute a valid alternative to increase crop productivity in a sustainable and environmentally friendly production scheme, reducing the application of agrochemicals. In a previous work, we described the characterization of bacteria belonging to Pseudomonas,Enterobacter and Klebsiella obtained from surface sterilized peanut nodules. In addition, we showed that some of these isolates were able to promote several peanut growth and symbiotic parameters. Bounded to the results from this particular study, and considering their potential ability to interact with different plant species, in this work we assessed the effects of their inoculation in maize (Zea mays L.) under controlled conditions. Furthermore, we analyzed growth promotion in a simulated peanut-maize crop rotation system. Finally, we determined the plant growth promoting (PGP) properties present in the isolates. Results indicated that all bacteria are able to significantly promote maize and peanut growth, and that they also displayed plant growth promotion activity in maize growing in a peanut-maize crop rotation sequence.
Journal of Biosciences, 2014
Plant-growth-promoting bacteria are often used to enhance crop yield and for biological control o... more 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. [Figueredo MS, Tonelli ML, Taurian T, Angelini J, Ibañez F, Valetti L, Muñoz V, Anzuay MS, Ludueña L and Fabra A 2014 Interrelationships between Bacillus sp. CHEP5 and Bradyrhizobium sp. SEMIA6144 in the induced systemic resistance against Sclerotium rolfsii and symbiosis on peanut plants.
ISRN Ecology, 2011
The present study investigated bacterial diversity associated with the roots of maize through the... more The present study investigated bacterial diversity associated with the roots of maize through the use of culture-dependent and culture-independent methods. Bacterial 16S-23S rDNA internal transcribed spacer sequences (ITS) primers were used to amplify sequences obtained directly from the root matrix by Percoll gradient separation. This assay showed that γ-Proteobacteria within Enterobacter, Erwinia, Klebsiella, Pseudomonas, and Stenotrophomonas genera were predominant groups. The culturable component of the bacterial community was also assessed, revealing that the predominant group was Firmicutes, mainly of Bacillus genus, while Achromobacter, Lysinibacillus, and Paenibacillus genera were rarely found in association with the roots. Only two genera within γ-Proteobacteria, Enterobacter and Pseudomonas, were found in the culture collection. Differences in richness and diversity between the rhizospheric and endophytic bacterial communities were also evidenced. The spectrum of bacteria naturally associated with maize roots is wide and the magnitude of such diversity will depend on the methods chosen for analysis. The knowledge of this spectrum will facilitate the search of microorganisms capable of exerting antagonism to diverse pathogens or detecting plant growth enhancers.
Endangered Waterbirds at Doñana Natural Space
Biological Monitoring in Freshwater Habitats, 2009
The declarations of both Doñana Biological Reserve in 1964 and Doñana National Park in 1969 were ... more The declarations of both Doñana Biological Reserve in 1964 and Doñana National Park in 1969 were based mainly on the presence of the Iberian lynx Lynx pardinus and the Spanish imperial eagle Aquila adalberti: two species endemic to the Iberian Peninsula that have been very ...
Peanut nodulation kinetics in response to low pH
Plant Physiology and Biochemistry, 2005
In this work, the peanut nodulation kinetics by acid-sensitive and tolerant isolates under acid s... more In this work, the peanut nodulation kinetics by acid-sensitive and tolerant isolates under acid stress condition was analyzed. The results demonstrated that the acid pH produced a decrease in the number of nodules formed only when peanut plants were inoculated with acid-sensitive isolates but increased steadily by the addition of 10 mM Ca2+, reaching higher values than those obtained at pH 7.0. On the contrary, the peanut nodulation by acid-tolerant isolates was not affected by this stressing condition. These data suggest that acid-tolerant isolates could be used as a potential source of strains for preparing highly effective inoculants for peanut plants growing in acid soils.
Plant and Soil, 2010
Pantoea sp J49 and the symbiotic nitrogen fixing bacterium Bradyrhizobium sp SEMIA 6144 on peanut... more Pantoea sp J49 and the symbiotic nitrogen fixing bacterium Bradyrhizobium sp SEMIA 6144 on peanut (Arachis hypogaea L.) growth Abstract In the present study, attempts were made to analyze the effect of co-inoculation with an efficient phosphate solubilising native isolate Pantoea sp J49 and the symbiotic nitrogen fixing Bradyrhizobium sp SEMIA 6144 strain on Arachis hypogaea L. plants growth. Single and coinoculation of peanut plants growing in plastic pots containing soil with low P content were developed. Plants were harvested at R1 and R4 growth stages and were analyzed in different growth parameters. Survival of strain Pantoea sp J49 was analyzed in soil samples and in root tissues. Plants inoculated only with Pantoea sp J49 showed the highest shoot and root weight in both reproductive growth stages evaluated. Plants co-inoculated with this strain and Bradyrhizobium sp SEMIA 6144 showed increase in aerial dry weight at R1 stage. Survival assays demonstrated that Pantoea sp J49 survives not only in the peanut rhizosphere but also inside plant tissues, including nodules formed when it was co-inoculated with Bradyrhizobium sp SEMIA 6144. Results obtained in this study confirm the great potential of the native Pantoea sp J49 isolate in the promotion of peanut plant growth, probably related with its capacity to solubilise phosphate.
Structure-reactivity relationships in the aminolysis of O-ethyl S-aryl dithiocarbonates in aqueous solution
The Journal of Organic Chemistry, 1993
... Enrique A. Castro,' Mark Cubillos, Fernando Ibhiiez, Inge Moraga, and Jose G. Santos... more ... Enrique A. Castro,' Mark Cubillos, Fernando Ibhiiez, Inge Moraga, and Jose G. Santos' Facultad de Qulmica, Pontificia Uniuersidad Catblica de Chile ... of phenyl and p-nitrophenyl dithio-acetates the existence of a tetrahedral intermediate was inferred from curved koa vs [Nl plots ...
Kinetics and mechanism of the aminolysis of 2,4-dinitrophenyl and 2,4,6-trinitrophenyl O-ethyl dithiocarbonates
The Journal of Organic Chemistry, 1993
Page 1. J. Org. Chem. 1993,58,459-463 469 Kinetics and Mechanism of the Aminolysis of 2,4-Dinitro... more Page 1. J. Org. Chem. 1993,58,459-463 469 Kinetics and Mechanism of the Aminolysis of 2,4-Dinitrophenyl and 2,4,6-Trinitrophenyl O-Ethyl Dithiocarbonates Enrique A. Castro,' Fernando Ibaez, Mirtha Salas, Jose G. Sant08 ...
Kinetics and mechanism of the pyridinolysis of 2,4,6-trinitrophenyl acetate and 2,4,6-trinitrophenyl methyl carbonate
The Journal of Organic Chemistry, 1992
Page 1. J. Org. Chem. 1992,57,2691-2694 2691 of sodium in 50 mL of CH30H was kept at rmm temperat... more Page 1. J. Org. Chem. 1992,57,2691-2694 2691 of sodium in 50 mL of CH30H was kept at rmm temperature for 2.5 h. The solution was acidified with acetic acid. The solvent was evaporated under reduced pressure, and the ...
Journal of Applied Polymer Science, 2009
Some nonserious skin infections can be treated by hydration and antibacterial control. Microcapsu... more Some nonserious skin infections can be treated by hydration and antibacterial control. Microcapsules containing aloe-chitin are often used to treat this kind of problem. Microcapsules were applied to cotton fabrics by padding and sleeves were prepared. A hypoallergenic test was applied to the microcapsule emulsion and hydration of the epidermis was evaluated by capacitance methods. The fabric was sterilized by electron beam treatment to satisfy the antibacterial requisite. The results showed that the aloe is transferred from the fabric to the skin, increasing the level of skin hydration. The electron beam method was also shown to be effective for bacteria and fungi and had no effect on the microcapsule properties. It can, therefore, be confirmed that electron beam sterilization has no harmful effects on the type of microcapsule used in this study.
Interaction among Arachis hypogaea L. (peanut) and beneficial soil microorganisms: how much is it known?
Critical Reviews in Microbiology, 2010
The leguminous crop Arachis hypogaea L. (peanut) is originally from South America and then was di... more The leguminous crop Arachis hypogaea L. (peanut) is originally from South America and then was disseminated to tropical and subtropical regions. The dissemination of the crop resulted in peanut plants establishing a symbiotic nitrogen-fixing relationship with a wide diversity of indigenous soil bacteria. We present in this review, advances on the molecular basis for the crack-entry infection process involved in the peanut-rhizobia interaction, the diversity of rhizobial and fungal antagonistic bacteria associated with peanut plants, the effect of abiotic and biotic stresses on this interaction and the response of peanut to inoculation.
Jordi FIGUEROLA* 1, Luís GARCIA**, Andy J. GREEN*, Fernando IBAÑEZ**, Manuel MAÑEZ**, José Luís D... more Jordi FIGUEROLA* 1, Luís GARCIA**, Andy J. GREEN*, Fernando IBAÑEZ**, Manuel MAÑEZ**, José Luís DEL VALLE**, Héctor GARRIDO**, José Luís ARROYO** and Rubén RODRÍGUEZ** ... SUMMARY.Sex determination in glossy ibis chicks based on ...
Characterization of <i>Staphylococcus aureus</i> strains isolated from raw milk of bovine subclinical mastitis in Tehran and Mashhad
Acta Microbiologica et Immunologica Hungarica, 2011
Staphylococcus aureus is considered one of the most important food borne pathogens. A total of 11... more Staphylococcus aureus is considered one of the most important food borne pathogens. A total of 111 isolates of S. aureus were cultured from raw milk samples during January 2009 to June 2009 from Tehran and Mashhad. The coagulase gene polymorphism and the prevalence of classical enterotoxin genes of S. aureus strains were determined by PCR-RFLP (restriction fragment length polymorphism) and Multiplex-PCR. Disk diffusion method was used to determine the susceptibility of isolates to antimicrobial agents as instructed by Clinical and Laboratory Standards Institute. Sixty-seven % of the isolates harboured one or more enterotoxin genes. The most prevalent gene was sec, found in 59 % of the isolates. Approximately 8% of the isolates were positive for sea, seb and sed genes. Only one isolate had see gene. The rate of coexistence of enterotoxin genes was 14%. All S. aureus isolates were susceptible to ciprofloxacin, gentamicin, imipenem, minocycline, oxacillin and vancomycin. They were resistant to ampicillin (64%), penicillin (56%), clindamycin (22%), tetracycline (22%), doxycycline (19%), teicoplanin (13%), rifampin (2%) and trimethoprim-sulfamethoxazole (2%). On the basis of coagulase gene analysis of 111 S. aureus isolates, the PCR products of 56 isolates were digested with Alu I that produced three distinct patterns. These data indicate the high prevalence of enterotoxigenic S. aureus in raw bovine milk in Tehran and Mashhad, and highlight the importance of proper quality control of dairy products for public health.
GLORIA: The First Free Access e-Infrastructure of Robotic Telescopes for Citizen Science
Advances in Intelligent Systems and Computing, 2013
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Papers by Fernando Ibáñez