yacine benhizia

The bacteria hosted in the root nodules of the three Mediterranean wild legume species Hedysarum carnosum, Hedysarum spinosissimum subsp. capitatum, and Hedysarum pallidum, growing in native stands in different habitats in Algeria were isolated. Bacteria were recovered on yeast-mannitol-agar or on minimal media from a total of 52 nodules. Isolates were analyzed by Amplified Ribosomal DNA Restriction Analysis (ARDRA) using the enzyme CfoI, and further sorted by RAPD fingerprinting. A total of ten different types were found and their amplified 16S rDNA was sequenced and compared to databases. The BLAST alignment indicates that all the species whose sequences share 98 to 100% identity to the bacteria found in these nodules belong to the class Gammaproteobacteria and include Pantoea agglomerans, Enterobacter kobei, Enterobacter cloacae, Leclercia adecarboxylata, Escherichia vulneris, and Pseudomonas sp. No evidence of any rhizobial-like sequence was found even upon amplifying from the bulk of microbial cells obtained from the squashed nodules, suggesting that the exclusive occupants of the nodules formed by the three plants tested are members of the orders Enterobacteriales or Pseudomonadales. This is the first report of Gammaproteobacteria associated with legume nodules. Despite the presence of the related crop plant Hedysarum coronarium, specifically nodulated by Rhizobium sullae, these three Hedysarum species demonstrate to have undergone a separate path in terms of endophytic interactions with bacteria. An hypothesis to account for differences between the symbiotic relationships engaged by man-managed legumes, and those found in plants whose ecology is independent from human action, is discussed.

The Excel file represent the raw dataset of the accepted article of DEKAK et al. (2020).<br>Dekak, A., Menasria, T., Benhizia, Y., Chenchouni, H. (2020). Endophytic passenger bacteria associated with <i>Genista cinerea</i> nodules growing in North African drylands. <i>Rhizosphere. </i>https://doi.org/10.1016/j.rhisph.2020.100205<br>

Figure S1 for the article of DEKAK et al. (2020) entitled: "Endophytic passenger bacteria associated with <i>Genista cinerea </i>nodules growing in North African drylands". Rhizosphere. https://doi.org/10.1016/j.rhisph.2020.100205

Four spontaneous diploid taxa (2n = 2x = 16 chromosomes) of the genus Hedysarum L. were studied for the first time using molecular cytogenetic approach and a tetraploid one as an additional comparative control. This study follows the work undertaken on this genus as part of the preservation and valorization of fodder and pastoral phytogenetic resources in Algeria. Fluorescent in situ hybridization (FISH) results revealed the same number of 35S rDNA loci for all diploid taxa, but differences in the number and position of 5S ribosomal genes. Chromomycin fluorochrome banding displayed that all chromomycin positive bands (GC-rich heterochromatin) were colocalized with rDNA signals. 2C DNA values (genome size), estimated by flow cytometry, indicated greater than two-fold difference among diploid taxa where nuclear DNA amount ranged from 2C = 1.26 pg in H. carnosum Desf. to 2C = 3.36 pg in H. naudinianum Coss. Genome size of tetraploid H. perrauderianum Coss. & Durieu (2n = 4x = 32) also estimated for the first time, was 6.64 pg which is almost twice of the value of diploid H. naudinianum 2C = 3.36 pg. Palynological analysis by light microscopy shows two types of pollen grains: prolate and tricolpate for H. naudinianum and H. perrauderianum , subprolate and tricolporate for H. carnosum, H. spinosissimum subsp. capitatum (Desf.) Asch. & Gr. and H. pallidum Desf. These new data enrich the knowledge about relationships among these species and also allow proposing and discussing the possible origin of the tetraploid H. perrauderianum from the diploid H. naudinianum .

A phenotypic characterization of thirteen root nodule bacteria recovered from wild legumes ( and ) growing in arid eco-climate zones (Northeastern Algeria) was conducted using analysis of sixty-six phenotypic traits (carbohydrate and nitrogen assimilation, vitamin requirements, growth temperature, salinity/pH tolerance and enzyme production). Furthermore, SDS-PAGE profiles of total cell protein, antibiotic susceptibility and heavy metal resistance were performed. The results showed that the isolates can grow at pH 4 to 10, salt concentration (0-5%) and temperature up to 45 °C. The rhizobia associated with and were able to produce different hydrolytic enzymes including cellulose, pectinase and urease, with remarkable tolerance to toxic metals such as zinc, lead, copper, and mercury. Numerical analysis of the phenotypic characteristics revealed that the rhizobial isolates formed four main distinct groups showing high levels of similarity with The salt tolerant and heavy metals resista...

The bacteria hosted in the root nodules of the three Mediterranean wild legume species Hedysarum carnosum, Hedysarum spinosissimum subsp. capitatum, and Hedysarum pallidum, growing in native stands in different habitats in Algeria were isolated. Bacteria were recovered on yeast-mannitol-agar or on minimal media from a total of 52 nodules. Isolates were analyzed by Amplified Ribosomal DNA Restriction Analysis (ARDRA) using the enzyme CfoI, and further sorted by RAPD fingerprinting. A total of ten different types were found and their amplified 16S rDNA was sequenced and compared to databases. The BLAST alignment indicates that all the species whose sequences share 98 to 100% identity to the bacteria found in these nodules belong to the class Gammaproteobacteria and include Pantoea agglomerans, Enterobacter kobei, Enterobacter cloacae, Leclercia adecarboxylata, Escherichia vulneris, and Pseudomonas sp. No evidence of any rhizobial-like sequence was found even upon amplifying from the bulk of microbial cells obtained from the squashed nodules, suggesting that the exclusive occupants of the nodules formed by the three plants tested are members of the orders Enterobacteriales or Pseudomonadales. This is the first report of Gammaproteobacteria associated with legume nodules. Despite the presence of the related crop plant Hedysarum coronarium, specifically nodulated by Rhizobium sullae, these three Hedysarum species demonstrate to have undergone a separate path in terms of endophytic interactions with bacteria. An hypothesis to account for differences between the symbiotic relationships engaged by man-managed legumes, and those found in plants whose ecology is independent from human action, is discussed.

The Excel file represent the raw dataset of the upcoming article of DEKAK et al. (2018) entitled: "Characterization of root-nodulating bacteria isolated from Genista cinerea (Fabaceae) growing in North African drylands using Bayesian Markov chain Monte Carlo (MCMC) methods and 16S rRNA sequencing"

Des bacteries ont ete isolees a partir des nodules des especes de plantes legumineuses du genre Hedysarum : H. pallidum Desf., H. spinosissimum subsp. capitatum, H. carnosum Desf. et H. naudinianum Coss. Pour l’espece H. naudinianum Coss, c’est la premiere fois qu’une etude est faite pour mettre en evidence l’association symbiotique plante-bacterie. La caracterisation des bacteries isolees porte sur une identification phenotypique qui englobe une serie de tests en plus de la determination du profil proteique par SDS-PAGE et le test de nodulation et une caracterisation moleculaire des isolats. Les resultats de la caracterisation phenotypique et phylogenetique (l’ARDRA et le sequencage de l’ADNr16S) montrent que les isolats appartiennent a la classe des Gammaproteobacteria specifiquement les especes de Pseudomonas sp et Pantoea agglomerans

L'etude cytogenetique de l’espece Hedysarum pallidum Desf., endemique d’Afrique du Nord, est realisee sur des populations tolerantes a l’antimoine. Les resultats obtenus apportent des elements nouveaux sur la garniture chromosomique et le comportement meiotique de cette espece. Le caryotype de l’espece Hedysarum pallidum est etabli pour la premiere fois. Il est constitue de six paires metacentriques et deux paires submetacentriques dont l’une est satellifere; il se revele de type symetrique. La population temoin presente un nombre chromosomique constant alors qu’une variabilite intra et inter individuelle du nombre de chromosomes est observee chez  les populations tolerantes. Cette variabilite est due a la presence des chromosomes B de nature heterochromatique. Notons que l’etude du comportement  meiotique des populations tolerantes a revele l’existence de quelques anomalies. L’analyse du pollen a revele que celui-ci est viable a 90% pour toutes ces populations.

The nitrogen-fixing symbiosis fixation between legumes and Rhizobium helps the plant to survive and to compete effectively on nitrogen poor soils. The soil environment attached to the root system is characterized by intense microbial activity. This work aimed to study the diversity of indigenous rhizobia living in the rhizosphere of forage pea in eastern and central Algeria. Bacteria were trapped in vitro from collected soils. They were isolated from nodules by direct isolation or by bacterial trapping, and tested for nodulation. Further characterization was carried out to identify the isolates. Ninety-four isolates were obtained. Thirty-four were rhizobial strains that could, with two exceptions, establish root-nodule symbioses with the host plant. Different profiles of susceptibility to rhizobiophages indicated that the majority of isolates were likely to be members of the Rhizobium leguminosarum group of species. The strains revealed diverse plasmid profiles, and diverse restrict...