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Studying the genetic variability of local Mauritanian sorghum accessions holds significant importance within the context of sorghum improvement and development programs. Hence, this study aimed to explore the genetic diversity of sorghum accessions collected from different regions of Mauritania. We examined 30 sorghum accessions representing four populations, namely Hodh el Chargui, Hodh el Gharbi, Assaba, and Guidimagha, employing five Inter-Simple Sequence Repeat (ISSR) markers, which yielded 101 informative bands. Our examination of these sorghum populations revealed moderate genetic diversity, as indicated by the percentage of polymorphic bands (PPB = 86.7–100%), Nei's genetic diversity (He = 0.11–0.21), and Shannon's information index (I = 0.17–0.32). To evaluate genetic variation both within and among populations, we conducted an Analysis of Molecular Variance (AMOVA). Additionally, we used unweighted neighbor-joining-based cluster analysis, principal components analysis (PCoA), and structure analysis to elucidate population clustering. The Polymorphic Information Content (PIC) ranged from 0.25 to 0.30, with an overall mean of 0.27. Our AMOVA results revealed that 81% of the total genetic variation was within populations, with 19% among populations, with percentage of the genetic differentiation coefficient (Gst = 0.183). Cluster analyses did not exhibit distinct groupings of the studied populations based on their geographical origins. This observation is likely due to substantial gene flow (Nm = 2.23) among populations. Among the four populations we studied, those from Hodh El Gharbi (He = 0.18, %P = 66.34) and the Assaba region (Het = 0.21, %P = 67.33%) displayed the highest genetic diversity. Consequently, these areas hold potential as hotspots for identifying high-performing genotypes suitable for sorghum breeding programs. Furthermore, they are of paramount importance for the development of effective germplasm conservation strategies. [ABSTRACT FROM AUTHOR]

Maâmora is a cork oak forest in Morocco known for its production of sweet acorns. Genetic diversity and relationships were evaluated in 240 individuals from five Cantons. The nine inter simple sequence repeat (ISSR) primers used in this study generated 368 polymorphic fragments and showed 100% polymorphism. A moderate level of genetic diversity (I = 0.28, He = 0.173) was observed. The analysis of molecular variance (AMOVA) showed that the highest level of diversity occurred within the populations (75%). A genetic structure was obtained using unweighted pair group method with arithmetic mean (UPGMA) and principal coordinate analysis (PCoA) analyses. 39 alleles were generated with a mean of 557 alleles per locus using seven simple sequence repeats (SSR) markers to establish DNA-fingerprinting for genotyping of 47 "Plus" tree systematically characterized. The analysis of diversity revealed significant polymorphism (94%) and allelic richness with high observed heterozygosity, which was confirmed by the negative value of Fis (− 0319). Nm is equal to 10.23, and Gst and Fst are equal to 0.022 and 0.052, respectively, revealing low inter-population variability. Genetic typing of the entire collection of "Plus" trees has identify 47 different genotypes. Eight unique alleles and 16 genotypes with specific markers were identified in this study. These results could be used to select the genotypes of interest for the multiplication of seedlings for reforestation and breeding programs. [ABSTRACT FROM AUTHOR]

The objective of study aimed to analyze the genetic diversity and genetic structure of Moroccan landraces of sorghum (Sorghum bicolor L. Moench). Samples were obtained from 34 fields in the northern regions, specifically from Larache (13 fields), Tangier (11 fields), Chefchaouen (5 fields), and Tetouan (5 fields). A total of 398 individual plants were collected, including three accessions from each of the five cultivated races of sorghum (bicolor, durra, caudatum, guinea, and kafir) from the World Collection. Two molecular marker methods, inter-simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP), were employed. Four ISSR primers produced 185 reproducible bands, of which 177 (96%) exhibited polymorphism. Three AFLP primer combinations were used to detect 226 markers, out of which 198 (88%) were polymorphic. The average polymorphic information (PIC) values for ISSR and AFLP markers were calculated to be 0.98 and 0.97, respectively. Both markers revealed a higher relative genetic differentiation, with values of 0.5595 (ISSR) and 0.6216 (AFLP), while the gene flow (Nm) between fields was determined to be 0.3937 (ISSR) and 0.3043 (AFLP). Analysis of Molecular Variance (AMOVA) confirmed a greater variation within the field (57%). Classification of the Moroccan landraces based on Jaccard's similarity index led to the identification of two primary genetic pools, which was further supported by the unweighted pair group method with arithmetic mean (UPGMA) clustering and STRUCTURE analysis. The Mantel test revealed lack of correlation between genetic structure and microgeographical distribution. The ISSR and AFLP data suggest that the bicolor, durra, and caudatum races are more genetically related to the Moroccan landraces of sorghum than kafir and guinea. [ABSTRACT FROM AUTHOR]

Cork oak (Quercus suber L.) is an essential species of the Mediterranean region. In Morocco, it represents a source of life and is a noble species for many populations. The Maâmora forest, situated in Morocco, is recognized as the largest forest in the Mediterranean basin and displays the highest diversity compared to other forests in its distribution area. This study aimed to establish a genetic database of 240 individuals from Maâmora forest using seven SSR markers. Through a series of statistical analyses, we determined the level of diversity and genetic structure and created a core collection. Statistical analysis of the data showed a high degree of allelic variation, generating 47 alleles with an average of 6.71 alleles per locus. Furthermore, a high percentage of polymorphisms and a high Shannon index were observed. Intra-population genetic diversity was found to be high (86%) compared to inter-population diversity (14%). A low level of genetic differentiation (Gst = 0.12) and high gene flow were identified, consistent with the results obtained from the analysis of molecular variance (AMOVA). This suggests a possible capacity for the species to adapt to environmental conditions. A core collection of 18 genotypes was constructed, which included all the private alleles that were detected in this study. This core collection exhibited similar and crucial diversity to that identified in the initial collection, as verified by a series of genetic diversity and structural analyses. This research advocates populations and individuals for further studies on adaptation in order to improve and conserve this valuable resource in the future. [ABSTRACT FROM AUTHOR]

Plant Growth Promoting Rhizobacteria (PGPR) play an essential role in enhancing plant growth, health and yield. In this study, we describe the isolation of PGPR associated with the olive tree (Olea europaea L.) grown in three Moroccan regions of Zouala, Errachidia, and Essaouira. In these regions, we isolated 95 PGPRs from rhizosphere of Olive trees, 78% of them were characterized by their tolerance to a salinity of 4-11%. We also found that 39% of these PGPRs were phosphate solubilizing bacteria (PSB) with a solubilization ability greater than 100 µg/mL. In fact, Pantoea agglomerans (MRC_ZO_17) and Enterobacter ludwigii (MRC_ZO_97), showed the highest phosphate solubilization rates of ~450 µg/ mL and ~196 µg/mL, respectively. In addition to their ability to solubilize phosphate, various isolates had the ability to produce Indole-3-acetic acid (IAA). For instance, E. ludwigii (MRC_ZO_97) had an IAA production of ~60.48 g/mL. In the region of Zouala, characterized by relatively higher salinity and lower rate of organic matter, Firmicutes isolates account for 87% of the isolated rhizobacteria. Interestingly, we found that the olive tree-associated PGPRs vary significantly between the three sampled regions. Several rhizobacteria isolated in this study are excellent candidates for formulation as bioinocula for plants in saline soils. [ABSTRACT FROM AUTHOR]

The rhizosphere of olive trees (Olea europaea L.) is a source of bacteria with a high potential for biocontrol and plant growth promotion. In the present study, two native olive tree gram-negative bacteria were isolated from the rhizosphere of century-old trees in the region of Zouala (south-eastern Morocco), known for its arid climate and saline soils. The strains Pantoea agglomerans and Enterobacter ludwigii exhibited high tolerance to high PEG and NaCl concentrations, and significant plant growth-promoting (PGP) potential in vitro. The two strains efficiently solubilised phosphate in its two forms (TCP and RP), and Mica as a source of potassium and produced IAA. The two strains exhibited in vitro inhibition ability against Verticillium dahliae with partial inhibition of the growth of the mycelium by the strain P. agglomerans MRC_ZO_17. Greenhouse experiments showed that olive tree seedlings treated with the E. ludwigii MRC_ZO_97 strain significantly improved growth (dry weight) in the presence and absence of the pathogen compared to untreated plants, while the P. agglomerans MRC_ZO_17 strain showed significant effects on seedling growth only in the presence of the pathogen V. dahliae OV1 defoliating pathotype. Both strains showed high exopolysaccharides (EPS) production and good biofilm formation, making them excellent plant growth-promoting rhizobacteria (PGPRs) and Biological Control Agents (BCAs) with great potential to survive in soil under stress conditions. [ABSTRACT FROM AUTHOR]

Morocco is one of the most important regions of the world in terms of Quercus suber L. number and variation. This species is in decline due to several factors, which can lead to permanent loss of this resource. It would be essential to evaluate the genetic diversity in order to conserve maximum genetic variability of this species. The genetic diversity and differentiation of 16 sites from five regions representing the entire range of Moroccan Cork Oak were assessed. Twenty-three ISSR primers used generated 985 polymorphic fragments with an average of 42.8 bands per primer and showed 100% of polymorphism. The 173 individuals revealed a moderate level of genetic diversity at species level (I = 0.27, He = 0.161). The AMOVA showed that the highest level of diversity occurred within populations (64%), this was also confirmed by the coefficient of differentiation (Gst = 0.47). The estimated gene flow (Nm = 0.56) and the Mantel test revealed a significant correlation between geographic and genetic diversity (r = 0.266; p = 0.001). This genetic structure was further shown by the topology of the UPGMA, sPCA and STRUCTURE analysis. In addition, a core collection of 34 genotypes was established representing the essential diversity detected. This research advocates populations and individuals to preserve in order to improve and conserve this resource in the future. [ABSTRACT FROM AUTHOR]

Argan Tree is well known for its precious oil extracted from its seeds particularly used for the nutritional and cosmetic benefits. Because of the high international demand, the argan tree suffers from overexploitation and its cultivation is rare. Thus, the assessment of the genetic variation of this endemic tree is critically important for designing conservation strategies. In the present study and for the first time, genetic diversity of the global natural distribution of argan tree ( Argania spinosa L.) in Morocco was assessed. Four IRAP (inter-retrotransposon amplified polymorphism) primer combinations and seven ISSR (inter-simple sequence repeat) primers amplified 164 and 248 scorable polymorphic bands respectively. Polymorphic information content (PIC = 0.27), resolving power (Rp = 15) and marker index (MI = 10.81) generated by IRAP primer combinations were almost identical to those generated by ISSR primers (PIC = 0.27, Rp = 9.16 and MI = 12). AMOVA analysis showed that 49% of the genetic variation was partitioned within populations which is supported by Nei's genetic differentiation (Gst = 0.5391) and the overall estimate of gene flow (Nm) being 0.4274. The STRUCTURE analysis, PCoA (principal coordinate analysis) and UPGMA (unweighted pair-group method with arithmetic mean) based on the combined data matrices of IRAP and ISSR divided the 240 argan genotypes into two groups. The strong differentiation observed might be due to the geographical distribution of argan tree. Our results provide crucial insight for genetic conservation programs of this genetic resource. [ABSTRACT FROM AUTHOR]

The cork oak (Quercus suber L.) has been the focus of research dealing with the conservation and reforestation of this species due to its economic importance and the problem of deforestation affecting it. The genetic diversity of this tree species, its main aspect of adaptation, has not been sufficiently studied. The Moroccan cork oak tree is found in the northern part of the country, where the fruits of the tree are soft corns. This forest tree species has undergone a strong decline due to many factors, including a significant loss of its biological diversity. While working within the national framework of protection and enhancement of this tree species, our research aimed to analyze and assess the phenotypic diversity of different provenances, using qualitative and quantitative dendrometric traits and geographical characteristics such as the total height of the tree (H), the height to the first branch (Hbr), girth (Gir), surface coefficient of the bole (K) (K = (H Gir/200)), number of branches (NbrBr), vigor (V), foliage density (D), and altitude. The population of trees studied included 390 individuals from 6 regional provenances: the central plateau, Mamora, the Middle Atlas, the western Rif, the eastern Rif, and the Atlantic Rif. Univariate analysis showed a highly significant variability among these provenances. The highest coefficient of variation concerned K (62.79%) and Gir (42%), followed by NbrBr and Hbr with 32% and 30%, respectively. Hierarchical clustering led to the identification of 2 major groups, with the central plateau and eastern Rif representing the first group, and the Middle Atlas, western Rif, Atlantic Rif, and the Mamora forest representing the second group. The assembling of different groups as explained by dendrometric variation is mainly based on geographical traits. [ABSTRACT FROM AUTHOR]

Drought and desertification are the major environmental constraints facing the Sahelian agro-ecosystems for decades. Assessing genetic diversity of native tree species is critical to assist ecosystems restoration efforts. Here we describe genetic diversity and structure of seven Balanites aegyptiaca L. natural populations distributed across the Sahelian-Saharan zone of Mauritania using 16 polymorphic ISSR primers. These generated 505 polymorphic bands. Polymorphism information content (PIC) varied from (0.13–0.29) with an average 0.23, marker index (MI) averaged 7.3 (range 3.3–10.3) and resolving power (RP) ranged from (4.53–14.6) with an average 9.9. The number of observed alleles (Na) ranged from (0.62–1.39), Effective number of alleles (Ne) varied from (1.26–1.37), Shannon's information index (I) ranged from (0.25–0.36). AMOVA analysis showed that 80% of the genetic variation was fined within populations, which is supported by a low level of genetic differentiation between population (GST = 0.21) and an overall estimate of gene flow among populations (Nm = 1.9). The dendrogram based on Jaccard's similarity coefficient and the structure analysis divided the seven populations into two main clusters in which two populations from the Saharan zone were grouped. Our results provide baseline data for genetic conservation programs of this Sahelian neglected crop and with an important econ-ecological role. [ABSTRACT FROM AUTHOR]