10 research outputs found
Analysis of agromorphological diversity of southern Tunisia faba bean (Vicia faba L.) germplasm
Forty two faba bean landraces (traditional farmers’ varieties) (Vicia faba L.) from southern Tunisia, belonging to 8 oasis agro-ecosystems were assessed using morphological descriptors. The studied descriptors focused on morpho-phenological and morpho-agronomical traits. The data obtained is extracted on the basis of 35 descriptors of 42 populations from 8 localities, at a rate of 30 replications (plants) per population, in totality of 1260 individuals. The data underwent an analysis of variance and a multivariate analysis. Significant differences among populations for the thirty five descriptors were observed. The multivariate analysis performed on averages of all parameters revealed eight main groups, and variation within the same oasis agro-ecosystems was extremely important. Particularly, the group of ‘Tozeur’ made up of five populations (P38, P39, P40, P41 and P42), and the group of ‘Medenine’ composed of seven populations (P19, P20, P21, P22, P23, P24 and P25) showed a special characters than the other populations especially for seedling characters. The geographical location did not seem to be the main factor structuring the variability of the studied landraces. There proved to be substantial phenotypic variability in the Tunisian faba bean germplasm.Keywords: Diversity analysis, germplasm, faba bean (Vicia faba L.), oasis agro-ecosystems, Southern Tunisi
Speciation and genetic diversity in Centaurea subsect. Phalolepis in Anatolia
14 p., mapas, tablasMountains of Anatolia are one of the main Mediterranean biodiversity hotspots and their richness in endemic species amounts for 30% of the flora. Two main factors may account for this high diversity: the complex orography and its role as refugia during past glaciations. We have investigated seven narrow endemics of Centaurea subsection Phalolepis from Anatolia by means of microsatellites and ecological niche modelling (ENM), in order to analyse genetic polymorphisms and getting insights into their speciation. Despite being narrow endemics, all the studied species show moderate to high SSR genetic diversity. Populations are genetically isolated, but exchange of genes probably occurred at glacial maxima (likely through the Anatolian mountain arches as suggested by the ENM). The lack of correlation between genetic clusters and (morpho) species is interpreted as a result of allopatric diversification on the basis of a shared gene pool. As suggested in a former study in Greece, post-glacial isolation in mountains would be the main driver of diversification in these plants; mountains of Anatolia would have acted as plant refugia, allowing the maintenance of high genetic diversity. Ancient gene flow between taxa that became sympatric during glaciations may also have contributed to the high levels of genetic diversity.This work was supported by the Spanish Ministerio de Ciencia e Innovación [project CGL2010/18631] and Generalitat de Catalunya [Ajuts a Grups de Recerca Consolidats 2014-SGR514-GREB]Peer reviewe
Genetic diversity of North African Thymus algeriensis in Tunisia: Population structure and implication for conservation
The genetic diversity within and among nine natural populations of Thymus hirtus Willd. subsp. algeriensis (Boiss. et Reut.) Murb. from different geographical and bioclimatic zones were assessed using Random Amplified Polymorphic DNA data. A total of 154 bands were generated from seven selected primers. 141 bands were polymorphic (P=91.56%). The genetic diversity within a population based on Shannon's index which was high (H' pop=0.307) and varied according to bioclimatic zones. Ahigh genetic differentiation among populations (G ST=0.335 and F{cyrillic} ST=0.296) was revealed, suggesting a population isolation and a low level of gene flow among them. The major proportion of the variation was attributable to individual differences within populations. The genetic structure is in accordance with geography distances. The Neighbour- joining tree based on Nei's and Li's genetic distance among individuals showed that individuals from each population clustered together. The UPGMA dendrogram based on F{cyrillic} ST values revealed three clusters each of them includes populations closuring to their geographical origin. The high genetic structure of populations resulted from genetic drift caused both by the habitat fragmentation and the low size of most populations. The in situ conservation should interest all populations. The ex situ conservation should be based on the collection of seeds rather within than among populations because of the maximum of variation was revealed within populations.Esta investigación fue financiada por una beca del Ministerio de Investigación, Ciencia y TecnologÃa y el Instituto Nacional de Ciencias Aplicadas y TecnologÃa (Beca de Investigación 99 / UR/09-10).Esta investigación fue financiada por una beca del Ministerio de Investigación, Ciencia y TecnologÃa y el Instituto Nacional de Ciencias Aplicadas y TecnologÃa (Beca de Investigación 99 / UR/09-10)Peer Reviewe
Inter-specific relationships among two Tunisian Thymus taxa: Thymus capitatus Hoffm. et Link. and Thymus algeriensis Boiss. et Reut. using molecular markers
Genetic relationships between two sympatric species Thymus capitatus Hoffm. et Link. and Thymus algeriensis Boiss. et Reut. (Thymus hirtus Willd. subsp. algeriensis Boiss. et Reut.) were assessed using random amplified polymorphic DNA (RAPD) markers. Eighteen natural populations from different geographical and bioclimatic zones were evaluated. The seven selected primers generated 121 RAPD markers for T. capitatus (103 polymorphic; P = 85.12%) and 154 for T. algeriensis (141 polymorphic; P = 91.56%). The genetic diversity within T. capitatus and T. algeriensis populations based on Shannon’s index was high (H’pop = 0.303 and 0.307, respectively). A high genetic differentiation was revealed (GST = 0.359 and ΦST = 0.284 for T. capitatus, GST = 0.335 and ΦST = 0.296 for T. algeriensis). The large proportions of the genetic variation were observed within populations for the two studied taxa. A high genetic population’s structure was also estimated by a principal component analysis (PCA). Unweighted pair-group method using arithmetic average (UPGMA) cluster analysis based on Nei and Li's coefficient among populations identified that T. algeriensis and T. capitatus populations were clustered into two distinct groups. The high genetic divergence between the two species corroborates their taxonomic status.Keywords: Genetic diversity, inter-specific relationships, molecular markers, Thymus capitatus, Thymus algeriensi
Phytochemical profile and biological activities of <i>Deverra tortuosa</i> (Desf.)DC.: a desert aromatic shrub widespread in Northern Region of Saudi Arabia
<p>The present study describes the chemical composition of the essential oil of different plant parts of <i>Devrra tortuosa</i>; <i>in vivo</i> and <i>in vitro</i> biological activities of plant extract and essential oils. Apiol was found to be the major component of the oil (between 65.73% and 74.41%). The best antioxidant activities were observed for the oil of flowers (IC50 = 175 μg/ml). The samples of stems and roots exhibit lower antioxidant activity (IC50 = 201 μg/ml and 182 μg/ml, respectively). The values of IC50 showed that the extracts of methanol exhibit the highest antioxidants activities (IC50 = 64.8 102 μg/ml). EOs showed excellent antifungal activity against yeasts with low azole susceptibilities (i.e. <i>Malassezia</i> spp. and <i>Candida krusei</i>). The MIC values of oils varied between 2.85 mg/mL and 27 mg/mL. The obtained results also showed that the plant extracts inhibited the germination and the shoot and root growth of <i>Triticum æstivum</i> seedlings.</p
The genus <i>Artemisia</i> L. in the northern region of Saudi Arabia: essential oil variability and antibacterial activities
<p>Four species of the genus <i>Artemisia</i> L. (<i>Artemisia monosperma</i>, <i>Artemisia scoparia</i>, <i>Artemisia judaica</i> and <i>Artemisia sieberi</i>) growing in the northern region of Saudi Arabia were investigated with respect to their volatile oil contents. The yield of oil varied between 0.30 and 0.41%, % (w/w). <i>A</i>. <i>monosperma</i> showed the highest number of compounds with 30 components representing 93.78% of oil composition. However, <i>A</i>. <i>judaica</i> showed the lowest number of compounds with only 16 components representing 87.47% of essential oil. <i>A</i>. <i>scoparia</i> and <i>A</i>. <i>sieberi</i> are both composed of 17 components, representing 97.14 and 94.2% of total oil composition. <i>A</i>. <i>sieberi</i> and <i>A</i>. <i>judaica</i> were dominated by spathulenol (30.42 and 28.41%, respectively). For <i>A</i>. <i>monosperma</i>, butanoic acid (17.87%) was a major component. However, <i>A</i>. <i>scoparia</i> was a chemotype of acenaphthene. (83.23%). Essential oil of studied species showed high antibacterial activities against common human pathogens.</p
Valorization of Lyophilized Olive Mill Wastewater: Chemical and Biochemical Approaches
Lipid composition and antioxidant activity have been carried out in order to valorize the composition of olive mill wastewater extracts with different solvents (supercritical carbon dioxide, n-hexane, dichloromethane and ethanol). The antioxidant activity was evaluated using ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-diphenyl-1-picrylhydrazyl) tests. The total phenolics and flavonoid contents were, also, determined. The chemical composition of the extracted oil was established, respectively, by gas chromatography–flame ionization detector and high-performance liquid chromatography methods. The results showed that the oleic acid and equivalent carbon number of forty-eight were the major compounds of the analyzed oils. Residual olive mill wastewater from the Sousse region displayed the highest DPPH radical-scavenging activity (31.10 ± 0.10 μg/mL). The chemical analysis of extracts of OMWs showed that the n-hexane fraction contained an abundance of oleic acid (61.62%) and an equivalent carbon number of forty-eight (53.14%). The best antioxidant activity was determined for the ethanol fraction (14.5 μg/mL). The final results showed a significant difference and variations in polar and apolar components. Moreover, n-hexane extracts showed high percentages of Monounsaturated fatty acids (MUFA) with 64% of OMWs oil composition and the dichloromethane extracts contained the largest amount of flavonoids (160.30 ± 1.70 mg EQ/g DM)