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The Euphorbia resinifera is melliferous and medicinal plant and one of the endemic species of Moroccan Atlas Mountains. It is very well known for its honey of high nutritional and therapeutic quality. The objective of our study is to characterize and evaluate the phenotypic variation of this spontaneous species. Seventeen qualitative and quantitative morphological characters related to the bush, stem, spine, flower, and fruit of the plant were used to assess the morphological variability of twelve natural populations collected from its geographical range in Morocco. The results of the analysis of variance showed significant differences between the studied populations for the most examined traits reflecting the existence of a high phenotypic variability within this species. The principal component analysis showed that E. resinifera populations were clustered in three distinct groups not related to mountain range type. The results highlight a high phenotypic diversity within studied populations of this species in Morocco. This work aims to study the phenotypic variability of E. resinifera to delineate conservation strategies and also to establish forms of rational economic exploitation.

Pistacia lentiscus L. is an indigenous species of considerable ecological and economic importance. An understanding of the patterns of genetic variation within and between Moroccan populations of this species is essential to design optimal genetic management strategies for its conservation. Here, inter simple sequence repeat (ISSR) technique was used to study genetic variation of 11 populations sampled from different regions in Morocco. The 13 primers used produced 121 bands which 110 bands (90.90 %) were polymorphic. The mean values of PIC, RP, I and Ht were 0.79; 4.89; 0.47 and 0.31 respectively, implying the important genetic variability between the studied populations. Moreover, AMOVA analysis showed that 58% of total genetic variability is accounted within population and 42% between populations. The UPGMA dendrogram and Bayesian model-based clustering approach identified five gene pools structured independently from the geographical origin of populations. These results indicate that the ISSRs markers used represent an efficient and important tool for the genetic analysis of the lentisk and the existence of a large genetic variability in this species in Morocco

Moroccan plum cultivars were genetically characterized for assessing diversity and relatedness. In this study, a total of 23 plum cultivars were analyzed using 14 Inter-Simple Sequence Repeat (ISSR) primers. A total of 100 bands were obtained, of which 84 were polymorphic (84%). The mean values of PIC, Rp, I and Ht were 0.45; 3.03; 0.42 and 0.27, respectively, implying the important genetic variability between the plum cultivars. Furthermore, the coefficient of genetic differentiation (GST) between all groups was 0.21 indicating that 21 % of total genetic variability was between groups and 79 % was within groups. The UPGMA dendrogram and Bayesian model-based clustering approach identified four gene pools of cultivars independently of their geographic origin and denomination. These results showed that the ISSRs markers can be a useful tool for detecting molecular polymorphism and to survey the genetic diversity in this fruit crop.

Metallic trace element (MTE) soil contamination is a serious problem needed to be urgently faced to ensure safe food supply and protect human health over the world. The present work is a potting experiment conducted using two levels of biochar (2.5%; 5%) and animal manure (10%; 20%) to investigate their potential role in soil improvement and development of maize seeds grown in a former iron mine soil. Results show that both amendments increased soil pH. A successful growth of maize has been observed in presence of both organic amendments. Plants were well developed with leaves which were large, green, and longer comparing to untreated contaminated soil suggesting that biochar and animal manure reduced physical symptoms of metal toxicity. Biochar and animal manure amendments increased almost all the measured morphological characteristics especially shoot length (biochar: 16.44 cm, animal manure: 18.26 cm, and untreated soil: 13.37cm) and dry biomass of shoots (biochar: 0.11 g, animal manure: 0.18g, and untreated soil: 0.05g) and roots (biochar: 0.29 g, animal manure: 0.17 g, and untreated soil: 0.16 g) as well as length and numbers of leaves and leaf area. However, more studies are needed to explore the amendment role on biochemical, physiological, and accumulation of MTE by maize.

This study was carried out to determine the effects of seven kinds of priming, gibberellic acid (GA), salicylic acid (SA), citric acid (CA), sodium chloride (NaCl), potassium chloride (KCl), zinc (Zn) and iron (Fe) on seed germination and seedling emergence of garden cress (Lepidium sativum) under arsenic stress. Results revealed that germination percentage (GP), seed vigor index (SVI), radicle length (RL), plumule length (PL) and tolerance index (TI) were significantly decreased when arsenic stress was augmented from 0 to 100 mg L−1. Nevertheless, primed seeds (hormo, nutri and halo-priming) increased seed germination and seedling emergence and tolerance index of L. sativum. Phytotoxicity was also reduced by priming practices. Meanwhile, priming with gibberellic acid (GA) had the most positive effects on measured traits. Generally, the order of the effect of priming treatments tested decreases by the following order: GA > CA > KCl > Fe > Zn > SA > NaCl. The result of this study is coherent with the hypothesis that under heavy metal stress, priming can develop seed germination performance and seedling emergence.

Cadmium accumulation in crops and the possibility of Cd entering the food chain are serious concerns for public health. This review discusses the deleterious effects of Cd in plants and the toleran...

In the present study, sheep manure (0%, 10% and 20% w/w) and biochar derived from coniferous tree woods (0%, 2.5% and 5% w/w) were incorporated into a multi-MTE contaminated soil from a former iron mine site and incubated for 10 days. A seeds of barley were grown in the amended soil and different morphological traits were measured after 30 days. Results indicated that MTE stress reduced the shoot length, stem diameter, leaf area, number of leaves and dry biomass as compared to the control. Organic amendments application increased soil pH and was found to affect significantly almost all the measured parameters. Animal manure was found effective in improvement of the morphological characteristics of barley plants comparing to biochar amendments. Our results suggested that animal manure could be used for reducing the effect of MTE on the morphological proprieties of barley grown in a former iron mine soil.

This work highlights the morphological diversity and characteristics that contribute to false identifications of Tamarix (Tamaricaceae) in Morocco. These difficulties of identification explain the controversy over the number of Tamarix species present in Morocco and around the world. Three taxa previously recorded in Morocco are confirmed : T. africana Poiret, T. boveana Bunge and T. aphylla Karst, while T. amplexicaulis Ehrenb could be present in a single station (Merzouga). Concerning other taxa : T. canariensis Willd and T. gallica L., their determination requires further study in view of their similarities., Ce travail met en évidence la diversité et les caractères morphologiques qui contribuent à des identifications fausses des Tamarix (Tamaricaceae) au Maroc. Ces difficultés d’identification expliquent la controverse sur le nombre d’espèces de Tamarix présentes au Maroc et dans le monde. Trois taxons précédemment recensés au Maroc sont confirmés : T. africana Poiret, T. boveana Bunge et T. aphylla Karst, alors que T. amplexicaulis Ehrenb pourrait être présent dans une seule station (Merzouga). Pour d’autres taxons : T. canariensis Willd et T. gallica L., leur détermination nécessite des études plus approfondies compte tenu de leurs ressemblances., Bihaoui Abdesslam, Haddioui Abdelmajid, Hammada Soumaya. Les erreurs d’identification des espèces du genre Tamarix L. au Maroc : clés non uniformes et espèces polymorphes / The identification errors of species of the genus Tamarix L. species in Morocco: non-uniform keys and polymorphic species. In: Ecologia mediterranea, tome 46 n°1, 2020. pp. 49-61.

The genetic diversity and genotypes structure of walnut (Juglans regia L.) are essential to understand and manage genetic resources of this species, as well as for further progress in breeding programs. ISSR markers were used to assess the genetic diversity of 66 individuals’ trees from 11 accessions, representing the main cropping area of walnut belonging to two ranges types of Mountain in Morocco: middle and high Atlas. Eleven ISSR primers rendered a total of 135 bands (91%) with 0.88 polymorphic information content. The utilization of 123 polymorphic bands revealed a high level of genetic variation within and among the examined accessions. The multi-locus values of Ht and Hs were 0.25 and 0.20, respectively. The AMOVA analysis showed that 71.30% of total genetic variability is accounted within accessions and 28.70% between accessions. This was congruent with the coefficient of genetic differentiation (GST=0.16). Bayesian model-based clustering approach identified three gene pools that were not correlated with mountain range type. This is the first application of ISSR markers for the assessment of genetic diversity in Moroccan germplasm of walnut. This information will be useful to define conservation strategies and improvement programs of this species.

In this work three heavy metals: cadmium (as CdSO4), cobalt (as CoCl2) and zinc (as ZnSO4), were used to determine and compare their toxicity towards two subspecies of barley (Hordeum vulgare subsp. vulgare L. and Hordeum vulgare subsp. distichum L.), focusing on seeds germination, seedlings growth, and cytological parameters. The results indicate that the effect of these heavy metals depends on the metal kind, the metal concentrations and the plant subspecies. Generally, in the case of H. vulgare, the heavy metal salts understudy did not influence significantly seed germination and seedling growth parameters. However, these metal salts influence significantly these parameters for H. distichum. The cytological test showed significant decrease (p < 0.05) in the mitotic index among the increase of the heavy metal concentrations when evaluated with the control for H. vulgare and H. distichum. Consequently, H. vulgare seemed to be more tolerant of the increase of the three heavy metals concentrations than H. distichum.

Northwest-African sheep represent an ideal case-study for assessing the potential impact of genetic homogenization as a threat to the future of traditional breeds that are adapted to local conditions. We studied ten Algerian and Moroccan breeds of sheep, including three transboundary breeds, distributed over a large part of the Maghreb region, which represents a geographically and historically coherent unit. Our analysis of the dataset that involved carrying out Genome-wide SNP genotyping, revealed a high level of homogenization (ADMIXTURE, NetView, fineSTRUCTURE and IBD segments analyses), in such a way that some breeds from different origins appeared genetically undistinguished: by grouping the eight most admixed populations, we obtained a mean global FST value of 0.0024. The sPCA analysis revealed that the major part of Morocco and the Northern part of Algeria were affected by the phenomenon, including most of the breeds considered. Unsupervised cross-breeding with the popular Ouled-Djellal breed was identified as a proximate cause of this homogenization. The issue of transboundary breeds was investigated, and the Hamra breed in particular was examined via ROH fragments analysis. Genetic diversity was considered in the light of historical archives and anthropological works. All of these elements taken together suggest that homogenization as a factor affecting the Maghrebin sheep stock, has been particularly significant over the last few decades, although this process probably started much earlier. In particular, we have identified the policies set by the French administration during the colonial period of the region’s history as a causal factor that probably contributed significantly to this process. The genetic homogenization that we have observed calls into question the integrity of the farm animal genomic resources represented by these local breeds, whose conservation is of critical importance to the future of the livestock sector.

In this research, we isolated and characterized Streptomyces strains, endemic from sugar beet fields of the Beni-Mellal region, able to use natural rock phosphate (RP) and tricalcium phosphate (TCP), as sole phosphate source. Ten Streptomyces isolates yielded a comparable biomass in the presence of these two insoluble phosphate sources, indicating that they were able to extract similar amount of phosphorus (P) from the latter for their own growth. Interestingly, five strains released soluble P in large excess from TCP in their culture broth whereas only two strains, BP, related to Streptomyces bellus and BYC, related to Streptomyces enissocaesilis, released a higher or similar amount of soluble P from RP than from TCP, respectively. This indicated that the rate of P released from these insoluble phosphate sources exceeded its consumption rate for bacterial growth and that most strains solubilized TCP more efficiently than RP. Preliminary results suggested that the solubilization process of BYC, the most efficient RP and TCP solubilizing strain, involves both acidification of the medium and excretion of siderophores. Actinomycete strains possessing such interesting RP solubilizing abilities may constitute a novel kind of intrans beneficial for plant nutrition and more environmentally friendly than chemical fertilizers in current use.

Phosphorus is a critical element to agriculture, consequently global phosphate rock demand will remain rising to feed a growing world population. The beneficiation of phosphorous ore gives rise to several tons of a waste by-product [phosphogypsum (PG)] which valorisation is limited, within other reasons, by the risks posed to environment and human health. Although threatening, the accumulation in stacks is the only procedure so far practiced by several countries as a means to get rid of this industrial externality. As part of a NATO Science for Peace Project (SfP 983311) this study describes the application of an environmental risk assessment (ERA) framework, to assess the risks posed by a PG stack to the surrounding soils, in Sfax, Republic of Tunisia. The ERA followed a weight of evidence approach, supported by two lines of evidence (LoE): the chemical (ChemLoE) and the ecotoxicological (EcotoxLoE). Integrated risks point for risk values greater than 0.5 in soils collected in PG stack surrounding area. Soil salinization, has likely contributed to the exacerbation of risks, as well as to the lack of consistency between both LoEs. This study highlights the need of rethinking the weight given to each LoE in ERA, in areas where soil salinization is a reality.

The walnut (Juglans regia L.) is a traditional fruit crop in Morocco. This species is cultivated in mountain in different environments. However, little data is available on its genetic diversity and its adaptability. Morphological characters of leaf and fruit from 11 Moroccan accessions of walnut were used to assess phenotypic variation of this species. Significant differences were found between accessions for the most examined traits, indicating a high phenotypic diversity. Multivariate analyses lead to identify three groups of accessions. The first group composed by the accessions of both Middle and High Atlas Mountain with high weigh and percentage of kernel and low thickness of shell. The second group included the accessions for the High Atlas Mountain characterised by large leaf, high nut dimension and great nut size. The third group is composed by two accessions, one belongs to the Middle Atlas Mountain and the other originating from High Atlas Mountain, which are characterized by small leaf and nut. Then, the structuration of accessions in three groups was not correlated to the mountain range type. Moreover, this study showed a significant phenotypic heterogeneity between the eleven studied accessions which opens the way for the strategies for their conservation and the selection of efficient genotypes with the desired traits.

In September 2020, during a field survey in the province of Berrechid (central Morocco), located in the region of Casablanca-Settat (33°18′35.3″N, 7°22′30.4″W), we found several Orobanche ramosa plants in Brassica rapa L. fields. After morphological identification, this will be added to the list of enemies of the turnip crop in the Chaouia-Ouardigha region (north-central Morocco). To our knowledge, this is the first time that O. ramosa has been reported on turnip in Morocco.

The concentrations of metals were determined in soil samples collected in Ait Ammar (Oued Zem, Morocco). The mean Cd, Cr, Cu, Fe, Pb and Zn contents in the mining topsoil samples were: 2.12, 135, 34.9, 214, 9.13 and 90.8 mg kg−1, respectively. Human health risks developed from metal ingestion, dermal absorption and inhalation of soils were also evaluated. For non-carcinogenic risks, united hazard index (HI) values for children surpassed the safe level (HI=1) for Cr (13.1). Values for HI in adults (1.74) also surpassed the safe level for Cr. The HI values for Pb and Cd for children were 0.69 and 0.68, respectively. Cancer risk due to Cr surpassed the tolerable range (1E-06 to1E-04) for children (1.05E-03) and for adults (1.42E-04). Cancer risks due to Pb and Cd were within acceptable ranges for both children and adults. Furthermore, oral ingestion of soil particles contributed more highly to both carcinogenic and non-carcinogenic risk from Cr than either dermal absorption or inhalation in both children and adults.

Millions of hectares in Africa, Europe, Asia, Australia, and America are contaminated of mine wastes. This contamination has caused a serious danger to humans, animals, plants, and microorganisms n...

Microbial communities in the soil were collected from 20 samples of an iron mining area (Ait Ammar, Oued Zem, Morocco), and unaffected samples were analysed to identify the effects of metal concentrations on functional diversity (Biolog® EcoPlates), and structural diversity (polymerase chain reaction-denaturing gradient gel electrophoresis of 16S rDNA). Aliivibrio fischeri is mainly used for evaluating polluted soil. The functional diversity was assessed by using such indices as area under substrate utilisation curve, richness, Shannon- Weaver and evenness indices. The analysis of similarities and the non-metric multidimensional scaling analyses of DGGE profiles showed that metals in the soil do not have a significant influence on bacteria. Principal component analysis of Biolog data revealed the similarity in the metabolic profiles of mining samples. These results suggest that the direction and the distance from the iron mine tailings do not have significant effects on the metabolic and structural diversity of the soil bacterial population. The toxicity of metals in soils heavily contaminated with Fe and P did not affect the quantities of microbial populations and did not significantly change the microbial diversity of contaminated soils.

Biochemical composition and antioxidant activity were determined in kernel nuts for eleven Moroccan walnut (Juglans regia L.) accessions representing its main cropping area. Total oil, carbohydrates, crude protein, energy value, crude fiber and flavonoid have varied significantly between accessions, respectively within the range values of 54.50-65.48%, 8.17-19.25%, 11.5-25.58%, 648.91-713.83 Kcal, 4.17-6.75% and 12.59-62.11mg RE 100 g-1 DM. Besides, mineral composition (mg 100 g-1) of kernel have varied also significantly among accessions and particularly for phosphorus (338.1-675.87), copper (2.08-6.67), zinc (3.39-18.63), iron (1.17-2.64), chromium (0.16-0.20), nickel (1.26-1.45) and boron (0.07-1.49). However, dry matter (96.75-98.56%), moisture (1.44-3.24%), ash (1.67-2.53%), total phenols content (1017-3739 mg GAE 100 g-1 DM), DPPH radical scavenging activity (75.02-85.96%), potassium (210.10-338.93 mg 100 g-1), magnesium (79.15-374.54 mg 100 g-1), sodium (1.17-12.63 mg 100 g-1) and manganese (0.79-1.67 mg 100 g-1) did not show significant variations between accessions. Furthermore, the results showed that Moroccan walnut constitutes an important source of nutrient elements, essentially fat, carbohydrates, protein, phosphorus and zinc, and natural antioxidants, phenolic compounds. Accordingly, consumption of all studied kernels accessions would be beneficial to health. This study showed considerable biochemical variation between the analyzed walnut accessions, which could help to select genotypes with desired traits according to their chemotypes.

This study was conducted to evaluate the effect of metals on wheat and bean species. The method uses seed germination and early seedling growth of these plants in the presence of various levels (10, 50, 100, 250, 500, 750 and 1000 mg/L) of Cadmium (Cd), Iron (Fe) and Zinc (Zn). The inhibition caused by these metals was depending on the concentration used, the metal itself and the plant species. The species had reduced seed germination, root and shoot lengths, tolerance index and percentphyto-toxicity with increasing concentrations of metals. Cadmium was determined to be the most inhibitory metal on these parameters. This metal affected significantly the germination, root and shoot length of the species tested, as well as the tolerance index and percentphytotoxicity starting from 50 mg Cd/l. Under the Iron stress, in general, the inhibition of germination and root length of wheat was reduced from 500 mg Fe/l. The results showed also that the inhibitory effect of increase of Zn levels was seen in root, shoot and tolerance indices. The findings also revealed that the metal toxicity was as follow: Cd > Fe > Zn. Regarding species, the results showed that bean seemed to be more tolerant to the increase of the three metals than wheat.

The aim of this study was to assess eleven Mediterranean pomegranate cultivars for drought tolerance based on their responses to severe water stress. The experiment was performed under field conditions in Sais Plain (NW Morocco) on twelve-year-old pomegranate trees (Punica granatum L.), under drip irrigation. For each cultivar, two treatments were applied from fruit set to harvest: a control treatment irrigated at 100 % of seasonal ETc (FI), and a continuous deficit treatment irrigated at 50 % of ETc (CDI). The measurements concerned fruit yield, fruit weight, aril content, aril weight, seed weight, juice content, shoot length, leaf area, foliage density, wood density and concentration of chlorophyll-a and chlorophyll-b. Results showed clear differences among pomegranate cultivars in response to water stress. The most frequent effects of water stress were recorded on yield, fruit weight and chlorophyll pigment contents. Fruit yield was not affected in Zheri Automne cultivar, while it was significantly decreased under CDI in all other cultivars by 14 % in Bzou to 51% in Ounk Hmam. A significant decrease of fruit weight was observed in six cultivars, with a rate of 13 % in Gordo de Jativa cultivar to 24 % in average for Grenade Jaune, Grenade Rouge and Ounk Hmam. These last cultivars were the only ones affected in juice content by 9–11%. Regarding CDI effect on vegetative growth, it was recorded a high decrease of shoot length in the cultivars Gjeibi (78 %), Sefri (64 %) and Mollar Osin Hueso (38 %). The cultivars ranking for drought tolerance based on mean ratios of all traits between CDI and FI treatments was drawn according to cluster analysis, combined to a scoring method. It was thus retained that the most drought tolerant cultivar was Zheri Automne, followed by Djebali and Bzou, while Grenade Rouge cultivar was the most sensitive.

Mining activity is an important economic activity in several North Atlantic Treaty Organization (NATO) and North African countries. Within their territory derelict or active mining explorations represent risks to surrounding ecosystems, but engineered-based remediation processes are usually too expensive to be an option for the reclamation of these areas. A project funded by NATO was performed, with the aim of finding a more eco-friendly solution for reclamation of these areas. As part of an overall risk assessment, the risk of contaminated soils to selected soil organisms was evaluated. The main question addressed was: Does the metal-contaminated soils from a former iron mine located at Ait Amar (Morocco),which was abandoned in the mid-Sixties, affect the reproduction of enchytraeids (Enchytraeus bigeminus) and predatory mites (Hypoaspis aculeifer)? Soil samples were taken at 20 plots along four transects covering the mine area and at a reference site about 15km away from the mine. The soils were characterized pedologically and chemically, which showed a heterogeneous pattern of metal contamination (mainly cadmium, copper, and chromium, sometimes at concentrations higher than European soil trigger values). The reproduction of enchytraeids (Enchytraeus bigeminus) and predatory mites (Hypoaspis aculeifer) was studied using standard laboratory tests according to OECD guidelines 220 (2004) and 226 (2008). The number of juveniles of E. bigeminus was reduced at several plots with high concentrations of Cd or Cu (the latter in combination with low pH values). There was nearly no effect of the metal contaminated soils on the reproduction of H. aculeifer. The overall lack of toxicity at the majority of the studied plots is probably caused by the low availability of the metals in these soils unless soil pH was very low. Different exposure pathways are likely responsible for the different reaction of mites and enchytraeids (hard-bodied versus soft-bodied organisms). The results of this study can be used not only for assessing the risk of contaminated soils but also could play a role for the identification of soil remediation programs.

The chloroplast rbcL gene is selected to be a standard barcode for the phylogenetic analyses of several land plants. Using universal primers pair, the 3’ frame was used to assess the phylogeny of the two Legume genera Medicago and Sulla and the evolution of the translated protein. The multiple alignment exhibited high conservation rates (97.56% and 96.43% for Medicago and Sulla respectively), which might be a brake for the phylogenetic assessment. Nevertheless, the topologies of the cladograms drawn using Maximum Likelihood method, showed a low intraspecific divergence and a slightly high interspecific variation, which confirms the efficiency of rbcL for such characterization’ analyses. Besides, the composition and the patterns of the Amino-Acid sequence and the deduced Codon Usage, highlighted a non-aleatoire distribution of the codons. Thus, the non-synonymous substitutions rates traduced a positive selection occurring in the rbcL of the Medicago and Sulla species.

Genetic diversity of 27 Moroccan pomegranate cultivars from three geographical regions of Morocco was screened using 61 Inter-Simple Sequence Repeat (ISSR) markers. Eight tested ISSR primers generated 70 bands of which 61 are polymorphic (87.14%). Nei's genetic distance ranged from (0.12 to 1) with a mean of 0.67. Nei genetic diversity parameters were 0.35 and 0.32 for Ht and Hs, respectively. Our results show considerable gene flow within and among pomegranate groups and a limited differentiation among groups as suggested by values of Gst (0.08) and Nm (5.80) parameters. The Unweighted Pair Group Method with Arithmetic Mean dendrogram and Principal Component Analysis clustered the pomegranate studied into two main clusters and did not show any relationships with the geographical origins of cultivars. Our results showed that ISSR markers can be a useful tool for detecting molecular polymorphism and studying the genetic diversity of pomegranate genotypes.

Background and Aims North Africa has a long history of viticulture and a wide diversity of grape cultivars. Ampelographic studies have been made of grapevine cultivars grown all over the world, but only a few describe those of Algeria and Morocco. Many Maghrebi cultivars held in germplasm banks or found growing wild in this region have recently been subjected to microsatellite profiling by different researchers, though little comparative analysis has been undertaken. The aim of the present work was to clarify the identity of the grapevine cultivars growing in the Maghreb via ampelographic and single-nucleotide polymorphism analysis. Methods and Results Seventy-one accessions were studied through the ampelographic construction of their mean leaves, via genotypic analysis using single-nucleotide polymorphism markers, and the comparison of these results with previously reported single sequence repeat marker profiles and ampelographic data for other grapevine material from the Maghreb. Conclusion New synonyms and homonyms were detected between Maghrebi cultivars. Some misinterpretations and errors of identification made during the making of the studied germplasm collections were identified. Significance of the Study This study helps clarify the confusion over the identity of Algerian and Moroccan grapevine cultivars and provides a general picture of grapevine diversity in the Maghreb.

Microsatellites are highly polymorphic and abundantly dispersed throughout eukaryotic genomes. The Medicago truncatula SSR (Simple Sequence Repeat) markers were used to study the genome of Sulla. Composed of six Mediterranean species, the genus Sulla constitutes an important phytogenetic resource, which are exploited either for protection and enrichment of soil, or for pastoral production. The greater transferability of 5 pairs of primers revealed 126 alleles and 148 genotypes. Except for Sulla pallida, a significant heterozygosity deficit (Hobs = 0.509) was shown. Results revealed that 23% of the variability is on the inter-specific level and 73% for the intraspecific level. The UPGMA highlighted the genetic proximity of Sulla carnosa and S. pallida. Our findings show the closeness of the six Sulla species due to the recent evolution of the complex Hedysarum-Sulla. This related proximity could be exploited in breeding programs to improve the damaged arid and semi-arid Mediterranean grasslands.

The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper.

Variability related to RAPD markers and sequences of nrDNA ITS region has been studied in seven species of the genus Atriplex (A. amnicola, A. canescens, A. halimus from Morocco (MAR) and from USA, A. lentiformis, A. nummularia, A. semibaccata and A. undulate). As a whole, the results show a high variability among the species. The biggest diversity was obtained by RAPD data, followed by ITSs. According to RAPD markers, two major groups can be distinguished, one formed by A. semibaccata and A. undulata, the least similar to the rest of species. A. lentiformis was closer to A. halimus. Phylogenetic analysis confirmed the divergence of A. semibaccata from all species and the closeness of A. lentiformis to A. halimus. The intraspecies variability was also high, as 39 individual RAPD haplotypes were obtained by analyzing 40 plants. Genetic diversity was bigger among species (60.23%) than among individuals (39.77%). The amplification of ITS region leads to three well-defined clades. The heterogeneous and larger clade includes all A. amnicola individuals and some individuals from A. nummularia, A. lentiformis, A. halimus USA, A. halilmus MAR and A. undulata. Both RAPDs and ITS analyses revealed with some exceptions, that all individuals from one species grouped together. RAPDS turn out to be more appropriate than ITS to differentiate Atriplex species. The two markers gave rise to the same species relationships, but to a different structure of the Atriplex genetic diversity. AMOVA analysis estimated interspecies differences for 11.20% of the total ITS variation. Both the great variability and the apparently restrictive gene flow among the species are discussed considering the life history and characteristics of the plants studied.

The halophyte plant, Atriplex halimus L., is of a great ecological and economical interest by its adaptation to the climatic and pedological conditions of the arid and semi-arid Mediterranean regions. This species, particularly adapted to arid and salt-affected areas, is used as a food for livestock forage, a wood source and a plant barrier against desert invasion (McKell 1989). In Morocco, A. halimus is widely distributed as a wild species. The description and the conservation of A. halimus genetic resources seem particularly important for the rehabilitation and disturbed areas by salt and low rainfall. Early study analysing the isoenzyme polymorphism, showed high genetic diversity in Moroccan populations of A. halimus (Haddioui & Baaziz 2001 ; Abbad et al. 2004a). In this study, the plant life history traits diversity of the same populations as studied by Haddioui & Baaziz (2001) was assessed using eleven morphological and phenological parameters. The morphological traits related with the ramification, leaves and fresh and dried mass production, which contributed mainly in the forage value of each plant were studied. The analysis of variance (ANOVA) has exhibited significant differences between populations for most of the morphological characters. Principal component analysis (PCA) highlighted two groups of population according to their geographical origin. The first group is composed by the littoral populations which are characterized by an increased vigour and high levels of forage production. All the remaining continental populations characterized by a weak vegetative development and low levels of forage production are clustered in the second group. This study showed a significant phenotypic heterogeneity between the nine studied populations. This variability is all the more significant as the populations are located in different climates., Dans une perspective de caractérisation des ressources naturelles d’Atriplex halimus L. au Maroc, la diversité phénotypique de neuf populations a été évaluée à l’aide de onze caractères morphométriques. Les paramètres phénologiques, l’aspect morphologique des rameaux et des feuilles et la production des matières fraîche et sèche d’A. halimus ont été étudiés, en raison de leur contribution à la valeur fourragère. Des différences significatives des paramètres phénologiques, de taille et de production des matières fraîche et sèche ont été observées entre populations. Deux groupes de populations ont été distingués par ACP. Le premier groupe est constitué des populations qui proviennent de stations littorales, caractérisées par des plantes plus vigoureuses ayant une biomasse fraîche et sèche élevée. Le second groupe est constitué de populations continentales caractérisées par des plantes moins vigoureuses ayant une biomasse fraîche et sèche faible., Haddioui Abdelmajid, Ould Mohamed Lemine Mohamed Mahmoud, Zinelabidine Lalla Hasna, Bouda Said. Variabilité phénotypique de la phénologie végétative et de la biomasse d’une espèce d’intérêt écologique et économique au Maroc : Atriplex halimus L.. In: Ecologia mediterranea, tome 34,2008. pp. 65-72.