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Due to their intensive cultivation, horticultural crops are particularly susceptible and vulnerable to the detrimental effects of drought stress, necessitating significant water inputs for optimal growth and yield. Accordingly, water-saving irrigation strategies, i.e., Partial Root zone Drying (PRD) and Regulated Deficit Irrigation (RDI) emerge as pivotal tools for bolstering the resilience of the horticultural sector. The current study aims to evaluate the impact of PRD and RDI strategies on pepper (Capsicum annuum L.) growth, and physio-biochemical attributes under semi-controlled greenhouse conditions. Research findings revealed pronounced enhancements in stem length under both irrigation strategies, with PRD exhibiting superior effects on shoot fresh and dry biomass (increases of 57.2% and 61.1%, respectively) compared to full irrigation. At the physiological level, PRD and RDI induced a significant reduction in stomatal conductance in pepper plants relative to full irrigation, while maintaining leaf water potential and relative water content. Biochemically, plants subjected to PRD and RDI methods exhibited significant accumulation of free proline, particularly pronounced with PRD (approximately 115.9% increase compared to full irrigation). Furthermore, Chl a and carotenoid concentration significantly increased under PRD, indicating sustained photosynthetic functionality. Comparatively, PRD appears as the more effective technique, offering the potential to conserve agricultural water about 50 without compromising growth parameters, while simultaneously enhancing tolerance traits in C. annuum. Nonetheless, further investigations on other traits across diverse soil types, climates, and cultivars under field conditions are imperative to ascertain the broader applicability of PRD and optimize its implementation.

Drought stress ranks among the most critical environmental challenges facing agriculture today, causing significant impairments to plant growth and development. In Morocco, these negative impacts are projected to intensify further under the combined pressures of climate change and the worsening water shortage crisis. The imperative need for sustainable arganiculture (cultivation of Argane trees) in dry lands necessitates the expeditious identification of drought-tolerant elite Argania spinosa trees. In this context, we investigated the drought tolerance of 2-year-old A. spinosa seedlings from two contrasting provenances Lakhssas (LKS) and Aoulouz (ALZ) under severe stress by evaluating their antioxidative defense mechanisms. A total of 24 parameters related to reactive oxygen species (ROS), oxidative damage, and enzymatic and non-enzymatic antioxidant defense were measured and compared between both provenances. The results showed that the drought-stressed conditions significantly increased the activity of enzymatic antioxidants, including superoxide dismutase, catalase, peroxidase, polyphenoloxidase, glutathione peroxidase, glutathione S-transferase, and ascorbate-glutathione cycle enzymes, as well as the content of non-enzymatic antioxidants, including reduced glutathione (GSH), ascorbic acid (AsA), α-Tocopherols (α-toc), polyphenols, anthocyanins, and group thiols. The ability of A. spinosa trees to greatly enhance their antioxidant system to limit cellular damage caused by ROS production might be an important attribute linked to drought tolerance. Regarding the inter-provenance variation under drought stress conditions, LKS provenance exhibited superior antioxidative capacity through enhanced AsA-GSH cycle activity and elevated levels of AsA-GSH, α-toc, and polyphenols. However, ALZ demonstrated elevated anthocyanin levels and reduced peroxidative stress markers (hydrogen peroxide and malonyldialdehyde). Significant and positive correlations were recorded between studied ROS and antioxidants. Investigating the multifaceted antioxidative defense system underpinning drought tolerance in A. spinosa can facilitate the identification of drought-tolerant argane trees for the development of a future breeding program allowing sustainable arganiculture in dry lands.

Understanding the adaptive mechanism of trees to climate change and effective management of genetic resources necessitate a comprehensive knowledge of the relationship between environmental factors and their adaptive power. This study focuses on the endangered Moroccan endemic tree, Argania spinosa L., known for its remarkable adaptive power in the Mediterranean climate and heavily impacted by climate change. Through genomic scans along a latitudinal gradient, we aimed to identify genomic regions associated with convergent or divergent selection by searching the genome for outlier loci demonstrating high population differentiation. Variation of dominant markers (Amplified Fragment Length Polymorphism) was correlated with variation of environmental factors to discern signals of natural selection in 13 natural populations of Argania spinosa L. along a latitudinal transect.Genotyping of 130 individuals with 477 AFLP markers revealed six outlier loci exhibiting elevated population differentiation values within argan forests. The BayeScan v2.1 software was used to detect outlier loci, and the (MLM) method strongly associated these loci with at least five environmental factors, particularly bioclimatic variables. Notably, all outlier loci exhibited significant correlations with Soil Moisture, with additional associations with Temperature, Precipitation, Landforms, and Soil Type, influencing the local adaptation of Argania spinosa L.The outlier AFLP loci may not be the direct targets of natural selection, but locate closely to genes that are potential involved in local adaptation. Consequently, further investigations are imperative to validate these candidate loci. This research underscores the significance of considering bioclimatic variables, especially Soil Moisture, in understanding the local adaptation of Argania spinosa L. amid climate change in Morocco.

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.

Fatty acid desaturase ( FAD ) is the key enzyme that leads to the formation of unsaturated fatty acids by introducing double bonds into hydrocarbon chains, and it plays a critical role in plant lipid metabolism. However, no data are available on enzyme-associated genes in argan trees. In addition, a candidate gene approach was adopted to identify and characterize the gene sequences of interest that are potentially involved in oil quality and abiotic stress. Based on phylogenetic analyses, 18 putative FAD genes of Argania spinosa L. ( AsFAD ) were identified and assigned to three subfamilies: stearoyl-ACP desaturase ( SAD ), Δ-12 desaturase ( FAD 2/ FAD 6), and Δ-15 desaturase ( FAD 3/ FAD 7). Furthermore, gene structure and motif analyses revealed a conserved exon-intron organization among FAD members belonging to the various oil crops studied, and they exhibited conserved motifs within each subfamily. In addition, the gene structure shows a wide variation in intron numbers, ranging from 0 to 8, with two highly conserved intron phases (0 and 1). The AsFAD and AsSAD subfamilies consist of three (H(X)2-4H, H(X)2-3HH, and H/Q (X)2-3HH) and two (EEN(K)RHG and DEKRHE) conserved histidine boxes, respectively. A set of primer pairs were designed for each FAD gene, and tested on DNA extracted from argan leaves, in which all amplicons of the expected size were produced. These findings of candidate genes in A spinosa L. will provide valuable knowledge that further enhances our understanding of the potential roles of FAD genes in the quality of oil and abiotic stress in the argan tree.

To enhance crop survival and yield, a comprehensive understanding of abiotic stresses responses is crucial. The aquaporin AQP gene family, renowned for its pivotal role in various physiological processes and environmental adaptations, offers potential for enhancing crop resilience. This systematic review aims to provide thorough insights into genome-wide analyses of aquaporin genes across various plant species. With the advent of whole-genome sequencing, genome-wide analyses have become indispensable for identifying novel AQP genes in plants. While numerous studies have reported the functional and structural characterization of these genes using in silico approaches, our approach involved a meta-analysis of papers available in various electronic databases, following predefined inclusion and exclusion criteria, up to November 2022. Incorporating 82 studies, this systematic review, collectively identified over 5200 AQP isoforms. The PIPs (1803), TIPs (1538), and NIPs (1297) subfamilies notably exhibited the highest number of isoforms, while SIPs and XIPs had 435 and 201 isoforms, respectively. Overall, this review constitutes a significant contribution, providing a comprehensive analysis of genome-wide data on plant aquaporin genes. It contributes to the understanding of the diverse roles of aquaporins and their isoforms, elucidating their functions and regulations across different plant species under various stress conditions.

Barley is an important crop worldwide known for its adaptation to harsh environments and used in multiple forms as feed, food and beverages. Its productivity is affected by major abiotic and biotic stresses. Scald caused by hemibiotrophic fungus Rhynchosporium commune is a major foliar disease in many parts of the world. Host plant resistance is targeted by breeders to efficiently control this disease. An association mapping panel of 316 spring barley genotypes (AM2017) was screened for seedling resistance in greenhouse against three R. commune isolates and for adult plant resistance in three field locations in Morocco. The phenotyping results showed different numbers of entries with resistant and moderately resistant reactions at both seedling and adult plant stages. The reactions differed between the isolates with the highest percentage of resistant genotypes observed for isolate SC-S611 (49.4%) and highest percentage of susceptible genotypes (73.8%) for isolate SC-1122. At adult plant stage, the highest percentage of scald resistant genotypes (64.5%) was observed at Rommani site compared to 56% at Guich site and only 28.8% at Marchouch site. Seven genotypes were resistant at the seedling and adult plant stages. Genome wide association study (GWAS) revealed 102 MTA (15 QTL) at the seedling stage, and 25 MTA (12 QTL) associated with scald resistance at the adult plant stage. In addition, the sequences of 92 out of 102 at SRT, and 24 out of 25 significant SNP markers at APR were located in genomic regions enriched with functional proteins involved in diverse cellular processes including disease resistance. These markers span over all chromosomes with the majority of SNPs located on 3H and 7H. This study has verified 18 QTL reported in previous studies. In addition, it was successful in identifying new sources of resistance and novel genomic regions which could help in enhancing scald resistance in barley breeding programs.

Cadmium (Cd) accumulation is one of the serious global issues among the multitude of food security challenges. Their toxic effects are evident in different physiological and metabolic behaviors of plants. In this context, a potted study was conducted to investigate the effectiveness of salicylic acid (SA) spraying in alleviating Cd toxicity in chia (Salvia hispanica) seedlings. This pseudocereal as a superfood is characterized by high nutritional value and high therapeutic potential. We examined some growth traits, photosynthetic pigments, anthocyanin, antioxidant defense system, malondialdehyde (MDA), and certain osmoregulatory molecules. The results showed that the chia seedlings exposed to Cd showed a substantial decline in growth, especially in shoot and root length and number of leaves (25.5, 21.5, and 22.6%, respectively), whereas the aforesaid biochemical parameters were not significantly affected. However, SA treatment alleviated the Cd stress applied and markedly enhanced the stem and root growth, especially shoot length of about 32.3% compared to Cd treatment. Under combined treatment Cd+SA, we also recorded a significant increase in the accumulation of proline (85.3%) and anthocyanin (83.1%), and a significant enhancement in peroxidase activity (34.9%), compared to control. These responses exhibit the involvement of SA in mitigating Cd-induced oxidative damage and improving Cd tolerance in Chia. Principal component analysis and cluster analysis showed differences between individual and combined treatment. Based on these results, exogenous SA used in the right amounts could alleviate Cd-induced stress and boost chia seedlings’ growth.

The current study aimed to analyze bacterial communities' diversity and abundance in three different deserted areas (Merzouga, Mhamid Elghizlane, and Erg lihoud) located in Moroccan Sahara, as well as to investigate osmotolerant microorganisms producing hydrolytic enzymes. The isolates were taxonomically affiliated using 16S rRNA gene sequencing. Four different hydrolase activities (amylase, lipase, cellulase, and protease) and osmotic stress tolerance were evaluated. The phylogenetic analysis of 364 screened isolates belonged to three phyla (Firmicutes 73%, Proteobacteria 26% and Actinobacteria 1%) and 18 different genera, from Bacillus, Ornithinibacillus, Paenibacillus, Geobacillus, Pseudomonas, Acinetobacter, Agrobacterium, Arthrobacter, Paenarthrobacter, Enterobacter, Staphylococcus, Erwinia, Herbasprillum, Ocuria, Massilia, Planomicrobium, Hodococcus, and Stenotrophomonas. The results detected a high proportion of osmotolerant and enzymes producing bacteria, many isolates can tolerate up to 55 °C (40%, 28%, and 30% in Merzouga, Mhamid Elghizlane, and Erg lihoudi, respectively). Meanwhile, the salinity tolerance reached 12% in some isolates with different proportions in each site, 29% in Merzouga, 24% in Mhamid Elghizlane, and 9% in Erg lihoudi. Furthermore, the enzymatic tests showed the presence of an amylolytic, lipolytic, cellulolytic, proteolytic activities in 20%, 31%, 63% and 72% of total strains, respectively. As a result, the present study is thus a preliminary yet critical step towards identifying the best bacterial candidates for further biotechnological applications.

Abstract Barley production worldwide is limited by several abiotic and biotic stresses and breeding of highly productive and adapted varieties is key to overcome these challenges. Leaf scald, caused by Rhynchosporium commune is a major disease of barley that requires the identification of novel sources of resistance. In this study two subsets of genebank accessions were used: one extracted from the Reference set developed within the Generation Challenge Program (GCP) with 191 accessions, and the other with 101 accessions selected using the filtering approach of the Focused Identification of Germplasm Strategy (FIGS). These subsets were evaluated for resistance to scald at the seedling stage under controlled conditions using two Moroccan isolates, and at the adult plant stage in Ethiopia and Morocco. The results showed that both GCP and FIGS subsets were able to identify sources of resistance to leaf scald at both plant growth stages. In addition, the test of independence and goodness of fit showed that FIGS filtering approach was able to capture higher percentages of resistant accessions compared to GCP subset at the seedling stage against two Moroccan scald isolates, and at the adult plant stage against four field populations of Morocco and Ethiopia, with the exception of Holetta nursery 2017. Furthermore, four machine learning models were tuned on training sets to predict scald reactions on the test sets based on diverse metrics (accuracy, specificity, and Kappa). All models efficiently identified resistant accessions with specificities higher than 0.88 but showed different performances between isolates at the seedling and to field populations at the adult plant stage. The findings of our study will help in fine-tuning FIGS approach using machine learning for the selection of best-bet subsets for resistance to scald disease from the large number of genebank accessions.

Background. The goal of Acute flaccid paralysis (AFP) surveillance is to comprehensively investigate and report any case of a child below 15 years with a floppy weakness. This is essential for the poliovirus eradication initiative. Objective. In this study, we analyzed the results of nine-year surveillance (2010–2018) of AFP in Morocco. Method. This was a descriptive, retrospective study of cases with AFP routinely documented at the National Referral Laboratory of Polio (NRLP) from 2010 to 2018. Results. Among the 884 AFP cases identified and analyzed, we identified 11 polioviruses as Sabin-like vaccine strains (PSL). PSL were isolated in 11 samples of AFP cases received at the laboratory, including one PSL1, three PSL2 + PSL3, one PSL1 + PSL2, and one PSL1 + 2 + 3. The annualized nonpolio AFP rate per 100,000 children under 15 years ranged from 0.84 during 2011–2015 to 2.29 in 2018. The stool adequacy indicator was poor and may be improved with better delivery times and maintaining the cold chain. The incidence of isolated nonpolio enteroviruses (NPEV) varied between 2.27% and 12.6%, with the average not exceeding 6.35%; the incidence remained low compared to the indicator set by the World Health Organization (WHO). Conclusion. Morocco was certified polio-free by WHO in 2015, and since then no cases of wild poliovirus have been reported. Overall, although the nonpolio AFP rate has risen to the WHO standard, stool adequacy and the proportion of nonpolio enteroviruses need to be improved. The laboratory can adopt alternative techniques, independent of cell culture, to ensure that imported cases of poliovirus are not missed, especially in this era of eradication.

The argan tree, Argania spinosa (L.) Skeels, is a horticultural forestry species characterized by its endemicity and adaptation to arid and semi-arid zones in the southwest of Morocco. Despite its limited geographical distribution, argan tree presents large genetic diversity, suggesting that improvement of argan is possible. This species plays important ecological, and socioeconomic roles in the sustainable development of the country. The integration of arganiculture into Moroccan agricultural policy has been implemented through a sector strategy, which is fully aligned with the conservation and regeneration of argan forest. A. spinosa is suitable for incorporation into different agroforestry productive systems under agro-fruit-forest model and its domestication will provide a powerful means of socio-economic and environmental management. Here, we provide an overview of the argan tree literature and highlight the specific aspects of argan stands, as agro-forest systems, with the aim of developing an adequate strategy of conservation and domestication of this species. We introduce promising programs and projects for argan plantations and arganiculture, which have been adopted to relieve anthropogenic pressure on the natural argan forest.

According to the Moroccan Court of Auditors, the meats are prepared in slaughterhouses that do not meet the basic conditions required by Moroccan standards. This survey is being conducted to assess the knowledge, attitudes, and practices of handlers regarding the salubrity and hygiene of meat and to evaluate the bacteriological load of work surfaces in a slaughterhouse located in the Marrakech region. A total of 100 people working at the slaughterhouse participated in the study. The average values concerning the attitude and practice of the carcass handlers were, respectively, very satisfactory (65.7%) and acceptable (53.44%), while the average value of knowledge was generally low (39%). Bacterial load was assessed by the serial dilution method using the standard procedure. Seventy samples were taken from the hands of manipulators, knives, clothes, hooks, door handles, floor, and walls over an area of between 20 and 100 cm2. The total number of aerobic mesophiles (TAVCs), Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella spp was determined for each sample. Escherichia coli was the predominant isolate (42%), while Salmonella spp and Pseudomonas aeruginosa were the least bacterial isolates with 16% and 14%, respectively. Walls and knives were the most contaminated by E. coli at 90%. This survey reveals the importance of developing formal training for all slaughterhouse handlers regarding meat hygiene and safety during carcass processing to develop their knowledge and practices. Bacteriological results indicate a need to improve the available slaughter facilities and develop an appropriate slaughter process strategy to minimize the risk of carcass contamination.

Durum wheat is an important crop for the human diet and its consumption is gaining popularity. In order to ensure that durum wheat production maintains the pace with the increase in demand, it is necessary to raise productivity by approximately 1.5% per year. To deliver this level of annual genetic gain the incorporation of molecular strategies has been proposed as a key solution. Here, four RILs populations were used to conduct QTL discovery for grain yield (GY) and 1,000 kernel weight (TKW). A total of 576 individuals were sown at three locations in Morocco and one in Lebanon. These individuals were genotyped by sequencing with 3,202 high-confidence polymorphic markers, to derive a consensus genetic map of 2,705.7 cM, which was used to impute any missing data. Six QTLs were found to be associated with GY and independent from flowering time on chromosomes 2B, 4A, 5B, 7A and 7B, explaining a phenotypic variation (PV) ranging from 4.3 to 13.4%. The same populations were used to train genomic prediction models incorporating the relationship matrix, the genotype by environment interaction, and marker by environment interaction, to reveal significant advantages for models incorporating the marker effect. Using training populations (TP) in full sibs relationships with the validation population (VP) was shown to be the only effective strategy, with accuracies reaching 0.35–0.47 for GY. Reducing the number of markers to 10% of the whole set, and the TP size to 20% resulted in non-significant changes in accuracies. The QTLs identified were also incorporated in the models as fixed effects, showing significant accuracy gain for all four populations. Our results confirm that the prediction accuracy depends considerably on the relatedness between TP and VP, but not on the number of markers and size of TP used. Furthermore, feeding the model with information on markers associated with QTLs increased the overall accuracy.

Isolated from desert, the nitrogen-fixing bacterium Ensifer aridi LMR001 is capable of survival under particularly harsh environmental conditions. To obtain insights in molecular mechanisms involved in stress adaptation, a recent study using RNAseq revealed that the RpoE2-mediated general stress response was activated under mild saline stress but appeared non-essential for the bacterium to thrive under stress and develop the symbiosis. Functions associated with the stress response included the metabolisms of trehalose, methionine, and inositol. To explore the roles of these metabolisms in stress adaptation and symbiosis development, and the possible regulatory mechanisms involved, mutants were generated notably in regulators and their transcriptions were studied in various mutant backgrounds. We found that mutations in regulatory genes nesR and sahR of the methionine cycle generating S-adenosylmethionine negatively impacted symbiosis, tolerance to salt, and motility in the presence of NaCl. When both regulators were mutated, an increased tolerance to detergent, oxidative, and acid stresses was found, suggesting a modification of the cell wall components which may explain these phenotypes and support a major role of the fine-tuning methylation for symbiosis and stress adaptation of the bacterium. In contrast, we also found that mutations in the predicted trehalose transport and utilization regulator ThuR and the trehalose phosphate phosphatase OtsB-encoding genes improved symbiosis and growth in liquid medium containing 0.4 M of NaCl of LMR001ΔotsB, suggesting that trehalose metabolism control and possibly trehalose-6 phosphate cellular status may be biotechnologically engineered for improved symbiosis under stress. Finally, transcriptional fusions of gfp to promoters of selected genes and expression studies in the various mutant backgrounds suggest complex regulatory interplay between inositol, methionine, and trehalose metabolic pathways.

Ulvan, carrageenan, alginate and laminarin were tested in olive trees’ twigs to elicit phenolic metabolism and control verticillium wilt of olive (VWO) caused by Verticillium dahliae. The elicitation effect was determined through phenylalanine ammonia-lyase activity, total polyphenol content and lignin content. VWO was assessed in twigs previously elicited (24 h) and maintained in a solution containing bio-elicitors (2 g/L) and conidial suspension (106 conidia/mL). Our results showed stimulation of the phenolic metabolism and the decline of wilt symptoms. Ulvan reduced significantly the area under the disease progress curve for severity to 39.9% and the final incidence to 28.9%. Ulvan and alginate produced significant inhibitory rates on mycelial growth of the fungus in vitro. Seaweed polysaccharides might help to overcome VWO by strengthening the host defense metabolism and restricting the pathogen’s growth.

Durum wheat (Triticum turgidum subsp. durum) is mostly grown in Mediterranean type environments, characterized by unpredictable rainfall amounts and distribution, heat stress, and prevalence of major diseases and pests, all to be exacerbated with climate change. Pre-breeding efforts transgressing adaptive genes from wild relatives need to be strengthened to overcome these abiotic and biotic challenges. In this study, we evaluated the yield stability of 67 lines issued from interspecific crosses of Cham5 and Haurani with Triticum dicoccoides, T. agilopoides, T. urartu, and Aegilops speltoides, grown under 15 contrasting rainfed and irrigated environments in Morocco, and heat-prone conditions in Sudan. Yield stability was assessed using parametric (univariate (e.g., Bi, S2di, Pi etc) and multivariate (ASV, SIPC)) and non-parametric (Si1, Si2, Si3 and Si6) approaches. The combined analysis of variance showed the highly significant effects of genotypes, environments, and genotype-by-environment interaction (GEI). The environments varied in yield (1370–6468 kg/ha), heritability (0.08–0.9), and in their contribution to the GEI. Several lines derived from the four wild parents combined productivity and stability, making them suitable for unpredictable climatic conditions. A significant advantage in yield and stability was observed in Haurani derivatives compared to their recurrent parent. Furthermore, no yield penalty was observed in many of Cham5 derivatives; they had improved yield under unfavorable environments while maintaining the high yield potential from the recurrent parent (e.g., 142,026 and 142,074). It was found that a limited number of backcrosses can produce high yielding/stable germplasm while increasing diversity in a breeding pipeline. Comparing different stability approaches showed that some of them can be used interchangeably; others can be complementary to combine broad adaption with higher yield.

The recently proposed species Ensifer aridi represents an interesting model to study adaptive mechanisms explaining its maintenance under stressful pedo-climatic conditions. To get insights into functions associated with hyperosmotic stress adaptation in E. aridi, we first performed RNAseq profiling of cells grown under sub-lethal stresses applied by permeating (NaCl) and non-permeating (PEG8000) solutes that were compared to a transcriptome from unstressed bacteria. Then an a priori approach, consisting of targeted mutagenesis of the gene encoding alternative sigma factor (rpoE2), involved in the General Stress Response combined with phenotyping and promoter gfp fusion-based reporter assays of selected genes was carried out to examine the involvement of rpoE2 in symbiosis and stress response. The majority of motility and chemotaxis genes were repressed by both stresses. Results also suggest accumulation of compatible solute trehalose under stress and other metabolisms such as inositol catabolism or the methionine cycling-generating S-adenosyl methionine appears strongly induced notably under salt stress. Interestingly, many functions regulated by salt were shown to favor competitiveness for nodulation in other rhizobia, supporting a role of stress genes for proper symbiosis’ development and functioning. However, despite activation of the general stress response and identification of several genes possibly under its control, our data suggest that rpoE2 was not essential for stress tolerance and symbiosis’ development, indicating that E. aridi possesses alternative regulatory mechanisms to adapt and respond to stressful environments.

Drought and high temperature are the major abiotic stresses for wheat production. The present study investigated the effect of drought and chronic heat stress on physiological parameters of durum wheat lines derived from interspecific crosses and their association with yield. Seventy-seven durum wheat lines were evaluated during two seasons (2016–2017 and 2017–2018) for drought tolerance at Tessaout (Morocco) using irrigated and rainfed treatments and for heat tolerance at Wad Medani (Sudan). Five drought screening indices (alone or combined) and physiological parameters were used to assess drought and heat tolerance. Among the physiological parameters used, canopy temperature (CT) had moderate heritability and was significantly affected by both severe and moderate drought stresses. CT at early heading showed a stronger correlation with grain yield (GY) and total biomass (BY) under heat stress. The use of maximum quantum yield of PSII (Fv/Fm) for drought/heat screening was limited by the low genetic variation despite its significant correlation with yield under drought (r2 = 0.22) and heat (r2 = 0.4). The normalized difference vegetation index (NDVI) at vegetative stage was highly correlated with GY and BY and it showed high genotypic variation that can allow for efficient selection. The grain filling rate (GFR) was found to be highly correlated with GY and BY under heat stress. The modified stress tolerance index (MsSTI) had the highest association with GY under drought (R2 = 0.82) while the mean productivity (MP) was adapted to both optimal conditions (R2 = 0.77) and drought stress (R2 = 0.73). The computation of a mean score index (MSI) improved the selection efficiency under drought (R2 = 0.92). The results showed good potential for lines derived from wide crosses to increase variability for heat and drought adaptive physiological traits.

A total of 14 Rhizobium strains were isolated from lentil accessions grown at the ICARDA experimental research station at Marchouch in Morocco and used for molecular characterization and symbiotic efficiency assessment. Individual phylogenetic analysis using the 16S rRNA gene, house-keeping genes rpoB, recA, and gyrB, and symbiotic genes nodD and nodA along with Multilocus Sequence Analysis (MLSA) of the concatenated genes (16S rRNA-rpoB-recA-gyrB) was carried out for the identification and clustering of the isolates. The symbiotic efficiency of the strains was assessed on three Moroccan lentil cultivars (Bakria, Chakkouf, and Zaria) based on the number of nodules, plant height, plant dry weight, and total nitrogen content in leaves. The results showed that the individual phylogenetic analysis clustered all the strains into Rhizobium laguerreae and Rhizobium leguminosarum with sequence similarity ranging from 94 to 100%, except one strain which clustered with Mesorhizobium huakuii with sequence similarity of 100%. The MLSA of the concatenated genes and the related percentages of similarity clustered these strains into two groups of Rhizobium species, with one strain as a new genospecies when applying the threshold of 96%. For symbiotic efficiency, the Bakria variety showed the best association with 10 strains compared to its non-inoculated control (p-value ≤ 0.05), followed by Chakkouf and Zaria. The present study concluded that the genetic diversity and the symbiotic efficiency of Rhizobium strains appeared to be mainly under the control of the lentil genotypes.

The preservation of the diversity of endangered populations of argan trees, in their natural habitat, is a crucial step toward their conservation. The aim of the present study was to evaluate the genetic diversity of the argan trees in the wild, and to establish a phylogenetic map using DNA fingerprints. The ultimate goal was to develop a core set that would represent the existing diversity in the whole germplasm. In regard to this, 200 samples of Argania spinosa individual trees were collected from 10 different provenances in the region of Essaouira (Morocco). The genetic variation between and within these argan trees was investigated using previously described Inter-Simple Sequence Repeat markers. These markers generated a total of 149 fragments, in which 148 (99.33%) were polymorphic. The samples collected in the ‘Ouled Lhaj’ provenance showed the lowest diversity (% of polymorphic locus P=48.32%; genetic diversity Nei h=0.153; allelic richness A=1.483), compared to those collected in the ‘Mramer’ provenance (%P=68.46%; h=0.233; A=1.685). Also, the results showed a high level of genetic differentiation among provenances (AMOVA=44%, Gst=0.40), and a limited gene flow (Nm=0.73) between the provenances. In addition, these data suggested a low correlation between the genetic diversity of the tree and their respective geographical location in relation to the proximity to the littoral. Finally, a core collection of 13 genotypes that represent the essential of the detected diversity was established. The distribution pattern of this genetic diversity provides an important baseline data for the conservation strategies of argan tree species in the wild.

Plant growth-promoting rhizobia are known to improve crop performance by multiple mechanisms. However, the interaction between host plants and Rhizobium strains is highly influenced by growing conditions, e.g., heat, cold, drought, soil salinity, nutrient scarcity, etc. The present study was undertaken to assess the use of Rhizobium as plant growth promoters under abiotic stress conditions. Fifteen Rhizobium strains isolated from lentil root nodules were tested for phosphate solubilization activity (PSA) and phytohormones production under salt and drought conditions. The results showed that 15 Rhizobium strains were significant phosphate solubilizers, and indole acedic acid (IAA) and gibberellic acid (GA3) producers based on least significant difference (LSD) analysis (p ≤ 0.05). The highest rate of PSA was attributed to three strains namely, 1145N5, 1159N11, and 1159N32 with a range of 144.6 to 205.6 P2O5 (µg/mL). The highest IAA production was recorded in the strain 686N5 with 57.68 ± 4.25 µg/mL as compared to 50.8667 ± 1.41 µg/mL and 37.32 ± 12.59 µg/mL for Rhizobium tropici CIAT 899 and Azospirillum brasilense DSM-1690, respectively. Strain 318N2111 produced 329.24 ± 7.84 µg/mL of GA3 as against 259.84 ± 25.55 µg/mL for A. brasilense DSM-1690. R. tropici CIAT 899 showed tolerance to salt (5% NaCl) and drought (ψ = −2.6 MPa) stress, whereas strain 686N5 showed an extremely high level of salt-tolerance (5% NaCl) and moderate level of drought tolerance (ψ = −0.75 MPa). These results indicate different pathways for drought and salt tolerance mechanisms. The assessment of plant growth promoting (PGP) activities of Rhizobium showed differences between bacterial viability and bacterial PGP activity in terms of abiotic stress tolerance where bacterial PGP activity is interrupted before reaching the bacterial tolerance threshold. These results integrate a new concept of PGPR screening based on PGP activity under abiotic stress.

Phytochemicals and antioxidant activity of fruits of 30 B. aegyptiaca trees naturally growing in the hyper-arid and arid zones in Mauritania were evaluated by following standard procedures. Ethnobotanical uses of fruit pulps and kernel were assessed using a structured questionnaire. Balanites aegyptiaca fruit pulp is a good source of sugars (33 g/100 g dry matter (DM)), polyphenols (264 mg GAE/100 g DM) and flavonoids (34.2 mg/100 g DM) with an average antioxidant activity of 519 µmol TEAC/100 g DM. The fruit kernel is rich in lipids (46.2 g/100 g DM) and proteins (29.5 g/100 g DM). Fruits from the hyper-arid zone exhibited high level of polyphenols, antioxidant activity and soluble tannins. Almost all of the informants (97.14%) reported the use of fruit pulp in folk medicine to treat diabetes, while 72.86% reported using the fruit pulp to treat hypertension. Kernel oil is mainly employed as ointments in the treatment of paronychia (57.14%) and dermal infections (35.71%). The predominant methods for preparing/administering fruit pulp/Kernel were maceration (58.8%), sucking fruit pulp (25.7%) and decoction (24.2%). Balanites aegyptiaca fruit contain both nutritional and health-promoting phytochemicals that could be of interest in the development of strategies for sustainable use of this neglected indigenous fruit tree.

Durum wheat is the 10th most important crop in the world, and its use traces back to the origin of agriculture. Unfortunately, in the last century only part of the genetic diversity available for this species has been captured in modern varieties through breeding. Here, the population structure and genetic diversity shared among elites and landraces collected from 32 countries was investigated. A total of 370 entries were genotyped with Axiom 35K array to identify 8,173 segregating single nucleotide polymorphisms (SNPs). Of these, 500 were selected as highly informative with a PIC value above 0.32 and used to test population structure via DAPC, STRUCTURE, and neighbor joining tree. A total of 10 sub-populations could be identified, six constituted by modern germplasm and four by landraces of different geographical origin. Interestingly, genomic comparison among groups indicated that Middle East and Ethiopia had the lowest level of allelic diversity, while breeding programs and landraces collected outside these regions were the richest in rare alleles. Further, phylogenetic analysis among landraces indicated that Ethiopia might represent a second center of origin of durum wheat, rather than a second domestication site as previously believed. Together, the analyses carried here provide a global picture of the available genetic diversity for this crop and shall guide its targeted use by breeders.

Heat stress occurring during the reproductive stage of wheat has a detrimental effect on productivity. A durum wheat core set was exposed to simulated terminal heat stress by applying plastic tunnels at the time of flowering over two seasons. Mean grain yield was reduced by 54% compared to control conditions, and grain number was the most critical trait for tolerance to this stress. The combined use of tolerance indices and grain yield identified five top performing elite lines: Kunmiki, Berghouata1, Margherita2, IDON37-141, and Ourgh. The core set was also subjected to genome wide association study using 7652 polymorphic single nucleotide polymorphism (SNPs) markers. The most significant genomic regions were identified in association with spike fertility and tolerance indices on chromosomes 1A, 5B, and 6B. Haplotype analysis on a set of 208 elite lines confirmed that lines that carried the positive allele at all three quantitative trait loci (QTLs) had a yield advantage of 8% when field tested under daily temperatures above 31° C. Three of the QTLs were successfully validated into Kompetitive Allele Specific PCR (KASP) markers and explained >10% of the phenotypic variation for an independent elite germplasm set. These genomic regions can now be readily deployed via breeding to improve resilience to climate change and increase productivity in heat-stressed areas.

Since the confirmation of measles cases represents an important indicator regarding the performance of the measles-elimination program, the aim of this study was to evaluate the effectiveness of the routine procedures followed in Morocco for the laboratory confirmation of measles cases. Suspected cases reported between January 2010 and December 2012 were assessed for the timeliness of the sample collection, occurrence of measles clinical symptoms, and the results of the laboratory diagnoses. For 88% of the 2,708 suspected cases, a clinical specimen was collected within 7d of rash onset, of which 50% were IgM-positive and 2.6% were equivocal. The measles symptoms were reported in 91.4% of the cases; the occurrence of symptoms showed a positive association with the serological results (odds ratio [OR] = 2.9883, 95% confidence interval [CI] 2.2238-4.0157). Of the negative samples, 52% (n = 116) tested positive by real-time polymerase chain reaction (PCR). These results are in favor of using molecular detection to complement serological diagnosis in the context of measles surveillance approach in Morocco. In addition, the introduction of additional laboratory methods for differential diagnosis is required for the final classification of suspected cases with maculopapular rash and fever in the context of the measles elimination program.

Diarrhea and respiratory diseases are the leading causes of morbidity and mortality among

Global warming may cause +4 °C temperature increases before the end of this century. Heat tolerant bred-germplasm remains the most promising method to ensure farm productivity under this scenario. A global set of 384 durum wheat accessions were exposed to very high temperatures occurring along the Senegal River at two sites for two years. The goal was to identify germplasm with enhanced tolerance to heat. There was significant variation for all traits. The genetic (G) effect accounted for >15% of the total variation, while the genotype by environment interaction (G × E) reached 25%. A selection index that combines G and a G × E wide adaptation index was used to identify stable high yielding germplasm. Forty-eight accessions had a stable grain yield above the average (2.7 t ha−1), with the three top lines above 3.5 t ha−1. Flowering time, spike fertility and harvest index were the most critical traits for heat tolerance, while 1000-kernel weight and spike density only had environment-specific effects. Testing of six subpopulations for grain yield across heat-prone sites revealed an even distribution among clusters, thus showing the potential of this panel for dissecting heat tolerance via association genetics.

Standard 24-locus Mycobacterial Interspersed Repetitive Unit Variable Number Tandem Repeat (MIRU-VNTR) typing allows to get an improved resolution power for tracing TB transmission and predicting different strain (sub) lineages in a community.During 2010-2012, a total of 168 Mycobacterium tuberculosis Complex (MTBC) isolates were collected by cluster sampling from 10 different Moroccan cities, and centralized by the National Reference Laboratory of Tuberculosis over the study period. All isolates were genotyped using spoligotyping, and a subset of 75 was genotyped using 24-locus based MIRU-VNTR typing, followed by first line drug susceptibility testing. Corresponding strain lineages were predicted using MIRU-VNTRplus database.Spoligotyping resulted in 137 isolates in 18 clusters (2-50 isolates per cluster: clustering rate of 81.54%) corresponding to a SIT number in the SITVIT database, while 31(18.45%) patterns were unique of which 10 were labelled as "unknown" according to the same database. The most prevalent spoligotype family was LAM; (n = 81 or 48.24% of isolates, dominated by SIT42, n = 49), followed by Haarlem (23.80%), T superfamily (15.47%), >Beijing (2.97%), > U clade (2.38%) and S clade (1.19%). Subsequent 24-Locus MIRU-VNTR typing identified 64 unique types and 11 isolates in 5 clusters (2 to 3isolates per cluster), substantially reducing clusters defined by spoligotyping only. The single cluster of three isolates corresponded to two previously treated MDR-TB cases and one new MDR-TB case known to be contact a same index case and belonging to a same family, albeit residing in 3 different administrative regions. MIRU-VNTR loci 4052, 802, 2996, 2163b, 3690, 1955, 424, 2531, 2401 and 960 were highly discriminative in our setting (HGDI >0.6).24-locus MIRU-VNTR typing can substantially improve the resolution of large clusters initially defined by spoligotyping alone and predominating in Morocco, and could therefore be used to better study tuberculosis transmission in a population-based, multi-year sample context.

Lead is a heavy metal of particular concern with respect to environmental quality and health. The lack of plant species that accumulate and tolerate Pb is a limiting factor to understand the molecular mechanisms involved in Pb tolerance. In this study we identified Hirschfeldia incana, a Brassicaceae collected from metalliferous mine spoils in Morocco, as a Pb accumulator plant. H. incana exhibited high Pb accumulation in mine soils and in hydroponic cultures. Major Pb accumulation occurred in the roots and a part of Pb translocated from the roots to the shoots, even to the siliques. These findings demonstrated that H. incana is a Pb accumulator species. The expression of several candidate genes after Pb-exposure was measured by quantitative PCR and two of them, HiHMA4 and HiMT2a, coding respectively for a P1B-type ATPase and a metallothionein, were particularly induced by Pb-exposure in both roots and leaves. The functional characterization of HiHMA4 and HiMT2a was achieved using Arabidopsis T-DNA insertional mutants. Pb content and primary root growth analysis confirmed the role of these two genes in Pb tolerance and accumulation. H. incana could be considered as a good experimental model to identify genes involved in lead tolerance and accumulation in plants.

BACKGROUND: Tuberculosis (TB) remains a major health problem in Morocco. Characterization of circulating Mycobacterium tuberculosis genotypic lineages, important to understand the dynamic of the disease, was hereby addressed for the first time at a national level. METHODOLOGY/PRINCIPAL FINDINGS: Spoligotyping was performed on a panel of 592 M. tuberculosis complex strains covering a 2-year period (2004-2006). It identified 129 patterns: 105 (n = 568 strains) corresponded to a SIT number in the SITVIT2 database, while 24 patterns were labeled as orphan. A total of 523 (88.3%) strains were clustered vs. 69 or 11.7% unclustered. Classification of strains within 3 large phylogenetical groups was as follows: group 1- ancestral/TbD1+/PGG1 (EAI, Bovis, Africanum), group 2- modern/TbD1-/PGG1 group (Beijing, CAS), group 3- evolutionary recent/TbD1-/PGG2/3 (Haarlem, X, S, T, LAM; alternatively designated as the Euro-American lineage). As opposed to group 3 strains (namely LAM, Haarlem, and T) that predominated (86.5% of all isolates), 6 strains belonged to group 2 (Beijing n = 5, CAS n = 1), and 3 strains (BOV_1 n = 2, BOV_4-CAPRAE) belonged to ancestral group 1 (EAI and AFRI lineage strains were absent). 12-loci MIRU-VNTR typing of the Casablanca subgroup (n = 114 strains) identified 71 patterns: 48 MITs and 23 orphan patterns; it allowed to reduce the clustering rate from 72.8% to 29.8% and the recent transmission rate from 64% to 20.2%. CONCLUSION: The M. tuberculosis population structure in Morocco is highly homogeneous, and is characterized by the predominance of the Euro-American lineages, namely LAM, Haarlem, and T, which belong to the "evolutionary recent" TbD1-/PGG2/3 phylogenetic group. The combination of spoligotyping and MIRUs decreased the clustering rate significantly, and should now be systematically applied in larger studies. The methods used in this study appear well suited to monitor the M. tuberculosis population structure for an enhanced TB management program in Morocco.