Nacer Ramdani - Academia.edu (original) (raw)

Papers by Nacer Ramdani

Research paper thumbnail of Caractérisation phénotypique des bactéries isolées des nodules racinaires de la légumineuse Spartium junceum L

« C'est le chemin du cactus qui mène à la gloire et non le chemin de jasmin » Fayza et Salima Déd... more « C'est le chemin du cactus qui mène à la gloire et non le chemin de jasmin » Fayza et Salima Dédicaces Mes très chers parents : Puisse ce modeste travail constituer une légère compensation pour tous les nobles sacrifices pour assurer mon bien être et mon éducation, vous m'avez toujours encouragé et soutenu, merci pour votre confiance et votre amour. A Mes très chers frères Avec qui j'ai passé les meilleurs moments de mon existence : Mokrane, Hakim et Nadir A Ma très chère soeur Nadjet que j'adore Mes dédicaces sont également adressées à tous mes cousins et cousines A Mes chères copines : Hadjila,

Research paper thumbnail of Caracterisation Phenotypique De Souches De Rhizobia Isolees De Quatre Especes De Medicago Dans La Vallee De La Soummam (Algerie)

10 souches de rhizobia ont ete isolees des nodules de 4 especes Medicago ( M. polymorpha, M. mini... more 10 souches de rhizobia ont ete isolees des nodules de 4 especes Medicago ( M. polymorpha, M. minima, M. arabica, M. orbicularis ), recoltees dans 4 sites de la vallee de la Soummam (Bejaia, Algerie). La caracterisation phenotypique a porte sur les aspects morphologiques, culturaux des colonies et physiologiques, par une serie de tests. Le traitement numerique des resultats des tests physiologiques regroupe les souches en 4 clusters formes a un faible niveau de similarite, indiquant leur diversite phenotypique

Research paper thumbnail of Caractérisation phénotypique des bactéries nodulant Vicia sativa L. et Vicia tetrasperma L

Research paper thumbnail of Symbiotic, phenotypic and genotypic characterization of Bradyrhizobium sp. nodulating Spartium junceum L. from Bejaia, northeastern Algeria

Symbiosis, 2020

Twenty-three bacterial strains were isolated from root nodules of Spartium junceum L., growing wi... more Twenty-three bacterial strains were isolated from root nodules of Spartium junceum L., growing wild in four distinct geographic locations in Bejaia city (Northeastern Algeria). They were analyzed based on their symbiotic effectiveness, phenotypic properties and restriction fragment length polymorphism of the 16S rRNA gene. In addition, sequence analyses of the ribosomal gene, protein-coding housekeeping genes glnII and recA, and symbiotic gene (nodC) were used to clarifying their taxonomic and phylogenetic position. Plant infection tests revealed that all strains were able to form nodules on their original host plant, but with variable nodulation ability and symbiotic effectiveness. All strains were slow-growing, alkali-producing rhizobia in YEMA medium. According to phenotypic test results, the strains were grouped in four main clusters in a UPGMA dendrogram, while they were discriminated into 12 distinct genotypes by 16S rDNA-RFLP. Phylogenetic analyses of 16S rRNA genes and two concatenated housekeeping genes, glnII and recA, distributed the representative strains from each RFLP genotypes into two major clades within Bradyrhizobium genus. Some of these strains were closely related to B. retamae and B. japonicum whereas others represented four novel genospecies. Based on analysis of the symbiotic gene sequence (nodC), all strains were placed in the symbiovar retamae cluster except for SjBA12 which possibly constitutes a new symbiovar within the genus Bradyrhizobium.

Research paper thumbnail of Vicia faba L. in the Bejaia region of Algeria is nodulated by Rhizobium leguminosarum sv. viciae, Rhizobium laguerreae and two new genospecies

Systematic and applied microbiology, Jan 27, 2017

Fifty-eight rhizobial strains were isolated from root nodules of Vicia faba cv. Equina and Vicia ... more Fifty-eight rhizobial strains were isolated from root nodules of Vicia faba cv. Equina and Vicia faba cv. Minor by the host-trapping method in soils collected from eleven sites in Bejaia, Eastern Algeria. Eleven genotypic groups were distinguished based on the combined PCR/RFLP of 16S rRNA, 16S-23S rRNA intergenic spacer and symbiotic (nodC and nodD-F) genes and further confirmed by multilocus sequence analysis (MLSA) of three housekeeping genes (recA, atpD and rpoB), the 16S rRNA gene and the nodulation genes nodC and nodD. Of the 11 genotypes, 5 were dominant and 2 were the most represented. Most of the strains shared high nodD gene sequence similarity with Rhizobium leguminosarum sv. viciae; their nodC sequences were similar to both Rhizobium leguminosarum and Rhizobium laguerreae. Sequence analyses of the 16S-23S rRNA intergenic spacer showed that all the new strains were phylogenetically related to those described from Vicia sativa and V. faba in several African, European, Amer...

Research paper thumbnail of Etude par spectroscopies IR et UV de la thermooxydation de films PEBD/amidon

Annales de chimie Science des Matériaux, 2007

Cet article a pour objet l'etude de la thermooxydation de films de polyethylene basse densite... more Cet article a pour objet l'etude de la thermooxydation de films de polyethylene basse densite/amidon par spectroscopies IR et UV. Les films sont obtenus a partir de formulations de polyethylene basse densite/amidon (amidon : 0, 4, 7, 9 et 15 % en poids) par compression. Ils ont ete exposes a la thermooxydation a differentes temperatures (80, 90 et 100°C). L'oxydation se manifeste par l'apparition de bandes d'absorption des carbonyles, centrees a 1715 cm -1 en IR et a 275 nm en UV. Apres une periode d'induction qui varie de 12 a 14 jours suivant la concentration d'amidon incorpore, l'indice des carbonyles augmente avec le temps et la temperature d'exposition. Durant les 30 premiers jours, la vitesse d'oxydation est d'autant plus faible que le pourcentage d'amidon dans les films de PEBD est grand.

Research paper thumbnail of Caractérisation phénotypique des bactéries isolées des nodules racinaires de la légumineuse Spartium junceum L

« C'est le chemin du cactus qui mène à la gloire et non le chemin de jasmin » Fayza et Salima Déd... more « C'est le chemin du cactus qui mène à la gloire et non le chemin de jasmin » Fayza et Salima Dédicaces Mes très chers parents : Puisse ce modeste travail constituer une légère compensation pour tous les nobles sacrifices pour assurer mon bien être et mon éducation, vous m'avez toujours encouragé et soutenu, merci pour votre confiance et votre amour. A Mes très chers frères Avec qui j'ai passé les meilleurs moments de mon existence : Mokrane, Hakim et Nadir A Ma très chère soeur Nadjet que j'adore Mes dédicaces sont également adressées à tous mes cousins et cousines A Mes chères copines : Hadjila,

Research paper thumbnail of Caracterisation Phenotypique De Souches De Rhizobia Isolees De Quatre Especes De Medicago Dans La Vallee De La Soummam (Algerie)

10 souches de rhizobia ont ete isolees des nodules de 4 especes Medicago ( M. polymorpha, M. mini... more 10 souches de rhizobia ont ete isolees des nodules de 4 especes Medicago ( M. polymorpha, M. minima, M. arabica, M. orbicularis ), recoltees dans 4 sites de la vallee de la Soummam (Bejaia, Algerie). La caracterisation phenotypique a porte sur les aspects morphologiques, culturaux des colonies et physiologiques, par une serie de tests. Le traitement numerique des resultats des tests physiologiques regroupe les souches en 4 clusters formes a un faible niveau de similarite, indiquant leur diversite phenotypique

Research paper thumbnail of Caractérisation phénotypique des bactéries nodulant Vicia sativa L. et Vicia tetrasperma L

Research paper thumbnail of Symbiotic, phenotypic and genotypic characterization of Bradyrhizobium sp. nodulating Spartium junceum L. from Bejaia, northeastern Algeria

Symbiosis, 2020

Twenty-three bacterial strains were isolated from root nodules of Spartium junceum L., growing wi... more Twenty-three bacterial strains were isolated from root nodules of Spartium junceum L., growing wild in four distinct geographic locations in Bejaia city (Northeastern Algeria). They were analyzed based on their symbiotic effectiveness, phenotypic properties and restriction fragment length polymorphism of the 16S rRNA gene. In addition, sequence analyses of the ribosomal gene, protein-coding housekeeping genes glnII and recA, and symbiotic gene (nodC) were used to clarifying their taxonomic and phylogenetic position. Plant infection tests revealed that all strains were able to form nodules on their original host plant, but with variable nodulation ability and symbiotic effectiveness. All strains were slow-growing, alkali-producing rhizobia in YEMA medium. According to phenotypic test results, the strains were grouped in four main clusters in a UPGMA dendrogram, while they were discriminated into 12 distinct genotypes by 16S rDNA-RFLP. Phylogenetic analyses of 16S rRNA genes and two concatenated housekeeping genes, glnII and recA, distributed the representative strains from each RFLP genotypes into two major clades within Bradyrhizobium genus. Some of these strains were closely related to B. retamae and B. japonicum whereas others represented four novel genospecies. Based on analysis of the symbiotic gene sequence (nodC), all strains were placed in the symbiovar retamae cluster except for SjBA12 which possibly constitutes a new symbiovar within the genus Bradyrhizobium.

Research paper thumbnail of Vicia faba L. in the Bejaia region of Algeria is nodulated by Rhizobium leguminosarum sv. viciae, Rhizobium laguerreae and two new genospecies

Systematic and applied microbiology, Jan 27, 2017

Fifty-eight rhizobial strains were isolated from root nodules of Vicia faba cv. Equina and Vicia ... more Fifty-eight rhizobial strains were isolated from root nodules of Vicia faba cv. Equina and Vicia faba cv. Minor by the host-trapping method in soils collected from eleven sites in Bejaia, Eastern Algeria. Eleven genotypic groups were distinguished based on the combined PCR/RFLP of 16S rRNA, 16S-23S rRNA intergenic spacer and symbiotic (nodC and nodD-F) genes and further confirmed by multilocus sequence analysis (MLSA) of three housekeeping genes (recA, atpD and rpoB), the 16S rRNA gene and the nodulation genes nodC and nodD. Of the 11 genotypes, 5 were dominant and 2 were the most represented. Most of the strains shared high nodD gene sequence similarity with Rhizobium leguminosarum sv. viciae; their nodC sequences were similar to both Rhizobium leguminosarum and Rhizobium laguerreae. Sequence analyses of the 16S-23S rRNA intergenic spacer showed that all the new strains were phylogenetically related to those described from Vicia sativa and V. faba in several African, European, Amer...

Research paper thumbnail of Etude par spectroscopies IR et UV de la thermooxydation de films PEBD/amidon

Annales de chimie Science des Matériaux, 2007

Cet article a pour objet l'etude de la thermooxydation de films de polyethylene basse densite... more Cet article a pour objet l'etude de la thermooxydation de films de polyethylene basse densite/amidon par spectroscopies IR et UV. Les films sont obtenus a partir de formulations de polyethylene basse densite/amidon (amidon : 0, 4, 7, 9 et 15 % en poids) par compression. Ils ont ete exposes a la thermooxydation a differentes temperatures (80, 90 et 100°C). L'oxydation se manifeste par l'apparition de bandes d'absorption des carbonyles, centrees a 1715 cm -1 en IR et a 275 nm en UV. Apres une periode d'induction qui varie de 12 a 14 jours suivant la concentration d'amidon incorpore, l'indice des carbonyles augmente avec le temps et la temperature d'exposition. Durant les 30 premiers jours, la vitesse d'oxydation est d'autant plus faible que le pourcentage d'amidon dans les films de PEBD est grand.