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One of the most restricting macronutrients for crop yield worldwide is phosphorus, which is often less than 1% of the total amount contained in soils. To promote its bioavailability, there are microorganisms considered vital that can solubilize and mineralize their pools in soils. In the current study, we assessed the potential of phosphate-solubilizing bacteria (PSB), isolated from the olive tree rhizosphere grown on phosphate sludge, to solubilize phosphate, promote plant growth, and tolerate abiotic stresses. Based on 16S rRNA gene sequencing, twenty-four PSB strains were identified and retained for in vitro analysis. According to the results, all the strains were able to solubilize the Moroccan rock phosphate, with soluble phosphate concentrations ranged from 5.34 µg/mL to 227 µg/mL. Furthermore, the majority of the strains are thermo-tolerant and halotolerant. Nonetheless, only five strains produced indole acetic acid. Regarding biocontrol potentialities, several PSB strains were characterized by producing hydrogen cyanide and hydrolytic enzymes (cellulase, and chitinase), of which three strains identified as Pseudomonas moraviensis, Bacillus cereus, and Bacillus aryabhattai, with a remarkable multi-trait combination were selected for antagonism and co-inoculation tests. The findings revealed that these PSB strains significantly inhibited Fusarium oxysporum (17.65%–62.35%) and Verticillium dahliae (52.35%–66.87%) and promoted common bean growth. The consortium of the three strains showed the best results by significantly increasing both plant height and tap root length and dry biomass compared to individual inoculation. The PSB selected from the olive tree rhizosphere growing on phosphate sludge have the potential to be useful as biofertilizer and biocontrol agents for attaining sustainable food crop production.

Salt stress is one of the major abiotic stresses that negatively affect crops worldwide. Plants have evolved a series of mechanisms to cope with the limitations imposed by salinity. Molecular mechanisms, including the upregulation of cation transporters such as the Na+/H+ antiporters, are one of the processes adopted by plants to survive in saline environments. NHX antiporters are involved in salt tolerance, development, cell expansion, growth performance and disease resistance of plants. They are integral membrane proteins belonging to the widely distributed CPA1 sub-group of monovalent cation/H+ antiporters and provide an important strategy for ionic homeostasis in plants under saline conditions. These antiporters are known to regulate the exchange of sodium and hydrogen ions across the membrane and are ubiquitous to all eukaryotic organisms. With the genomic approach, previous studies reported that a large number of proteins encoding Na+/H+ antiporter genes have been identified in many plant species and successfully introduced into desired species to create transgenic crops with enhanced tolerance to multiple stresses. In this review, we focus on plant antiporters and all the aspects from their structure, classification, function to their in silico analysis. On the other hand, we performed a genome-wide search to identify the predicted NHX genes in Argania spinosa L. We highlighted for the first time the presence of four putative NHX (AsNHX1-4) from the Argan tree genome, whose phylogenetic analysis revealed their classification in one distinct vacuolar cluster. The essential information of the four putative NHXs, such as gene structure, subcellular localization and transmembrane domains was analyzed.

Campylobacters are very important foodborne pathogens that raise the interest of food processors, researchers, as well as consumers and all stakeholders. Their contaminations can result in life threatening disorders, potentially leading to chronic sequelae such as Reiter’s and Guillain-Barre syndromes or Crohn’s Disease. Poultry has been identified as the main and most common reservoirs for Campylobacter. A survey was conducted in Morocco, from 2009 to 2012 to estimate the prevalence of Campylobacter in broiler chicken from about fifteen Moroccan cities that were most involved in the breeding of broilers. In this study, thermotolerant Campylobacter spp. were detected and identified from 165 samples by both cultural methods and molecular approaches based on polymerase chain reaction and 16S ribosomal RNA (rRNA) gene sequencing. The species were also genotyped by Restriction Fragment Length Polymorphism analysis. The conventional culture methods identified 97% of samples as positive for Campylobacter spp. The molecular approach based on 16S rRNA gene could not distinguish between C. jejuni, C. coli and C. lari. However, gyrB gene RFLP, allowed a good discrimination between the three species of Campylobacter. These results were also confirmed by Matrix Assisted Laser Desorption Ionization-Time of Flight and Mass Spectrometry proteomic profiling determination using libraries in the BioTyper 2.3 software. The present study identifies C. jejuni as the major source of contamination of poultry carcasses in Morocco. Key words: Campylobacter, chicken, 16S rRNA gene, gyrB gene, sequencing, RFLP-PCR, MALDI-TOF MS.

In this study, 19 ecotypes of Vicia ervilia (L.) Willd. sampled in the traditional agro ecosystems of the Rif mountains (Northwestern of Morocco) were investigated for their characteristics related to germination, phenology, morphology and yield. A large variation was determined among these traditional populations, especially among productive capacity traits as harvest index, which variation can reach up to 40%. The extent of phenotypic variation suggests an important genetic diversity. Indeed, despite a limited geographical scale, we have highlighted population differentiation linked to the production basin origin. Moreover, these populations are characterized by a short lifespan, the absence of dormancy together with precocity, which give to these landraces an interesting adaptive potentiality in the search for alternative crops tolerant to aridity and temperatures raises predicted by ongoing global changes. Key words: Vicia ervilia, landraces, Rif, ecotypes, genetic resources, alternative crops.

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.