Morphological and Anatomical Characteristics of Moroccan Fir Needles in Talassemtane National Park, North-Western Rif Region, Morocco

Moroccan fir, Abies maroccana Trab. forms a unique forest community in the Mediterranean basin and has a great ecological and biological values in Moroccan Rif Mountains. However, morphological and anatomical characters of the needles are poorly investigated for A. maroccana. This research examined the morphological and anatomical characters of Moroccan fir needles in order to determine the phenotypic needles traits of Abies maroccana. The study was carried out in the National Park of Talassemtane, Western Rif, Morocco. Data was collected from two-year-old needles in six stands. In each site, seven trees were selected, and 60 needles were collected from each tree. Five morphological and one anatomical characters of the needles were examined. The variance analysis (ANOVA) of quantitative needles variables revealed significant inter-tree morphological variability of needles of A. maroccana. Based on the morphological characters studied, the multivariate analysis (PCA) separated all trees of Moroccan fir into four groups: (A) long, thin and large; (B) long, thin and narrow; (C) short, large and thick; and finally (D) short and thick needles. As demonstrated here, the fir needles were mainly characterized by: 2 types of apex (obtuse–acute and acute needles), a broad base and the marginal resin canals. This diversity can be attributed to genetic variation and / or influence of ecological conditions

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Characterizing spatial structure of Abies marocana forest through point pattern analysis

Aim of study: Understanding small-scale patterns caused by stochastic factors or community interactions driving forest structure and diversity of Moroccan fir Abies marocana Trab.Area of study: Talassemtane fir forest, Talassemtane National Park, Rif Mountains, northern Morocco.Material and methods: Eight plots representative of the structural variability of A. marocana forests were selected, and all tree individuals with diameter at breast height (dbh) ≥2 cm were mapped and measured. We performed four types of spatial point pattern analyses: (1) Univariate analyses to explore the overall trees spatial pattern, (2) bivariate analyses to assess the spatial relationship between juveniles and A. marocana adults, (3) correlation between tree sizes (dbh) and distance between points pairs using the univariate mark correlation function, and (4) random labeling analyses between dominant and suppressed Moroccan fir individuals to assess competition patterns.Main results: We found a strong spatial aggregation of fir individuals and a positive intraspecific association between juveniles and adult trees. However, there were weak but significant distance-dependent effect on tree size and density-dependent effect on suppression pattern.Research highlights: Shade-tolerance, seed dispersal and/or microsite heterogeneity might play important roles in the observed fir patterns. Our results provide a basic knowledge on within-stand Moroccan fir spatial distribution, with implications for adaptive management of these relic forests, and prompting to further research to test advanced hypotheses.Additional key words: Moroccan fir; Talassemtane National Park; Rif forest; Spatial analysis; summary statistics; facilitation; aggregation.Abbreviations used: MF (Moroccan fir); Talassemtane National Park (TNP); dbh (diameter at breast height); Univariate pair-correlation function (g(r)); Heterogeneous Poisson (HP); Bivariate pair-correlation function (g12(r)); Univariate mark correlation function (kmm(r)), Mark connection function (p12(r))

Spatio-temporal variations and genetic diversity of Anaplasma spp. in cattle from the North of Tunisia

International audienceIn cattle, anaplasmosis is a tick-borne rickettsial disease caused by Anaplasma marginale, A. centrale, A. phagocytophilum, and A. bovis. To date, no information concerning the seasonal dynamics of single and/or mixed infections by different Anaplasma species in bovines are available in Tunisia. In this work, a total of 1035 blood bovine samples were collected in spring (n=367), summer (n=248), autumn (n=244) and winter (n=176) from five different governorates belonging to three bioclimatic zones from the North of Tunisia. Molecular survey of A. marginale, A. centrale and A. bovis in cattle showed that average prevalence rates were 4.7% (minimum 4.1% in autumn and maximum 5.6% in summer), 7% (minimum 3.9% in winter and maximum 10.7% in autumn) and 4.9% (minimum 2.7% in spring and maximum 7.3% in summer), respectively. A. phagocytophilum was not detected in all investigated cattle. Seasonal variations of Anaplasma spp. infection and co-infection rates in overall and/or according to each bioclimatic area were recorded. Molecular characterization of A. marginale msp4 gene indicated a high sequence homology of revealed strains with A. marginale sequences from African countries. Alignment of 16S rRNA A. centrale sequences showed that Tunisian strains were identical to the vaccine strain from several sub-Saharan African and European countries. The comparison of the 16S rRNA sequences of A. bovis variants showed a perfect homology between Tunisian variants isolated from cattle, goats and sheep. These present data are essential to estimate the risk of bovine anaplasmosis in order to develop integrated control policies against multi-species pathogen communities, infecting humans and different animal species, in the country

Influence of Bizerte city wastewater treatment plant (WWTP) on abundance and antibioresistance of culturable heterotrophic and fecal indicator bacteria of Bizerte Lagoon (Tunisia)

International audienc

A Tunisian patient with CLCN2‐related leukoencephalopathy

Abstract CLCN2‐related leukoencephalopathy (CC2L OMIM#: 615651) is a recently identified rare disorder. It is caused by autosomal recessive mutations in the CLCN2 gene and leads to the dysfunction of its encoded CLC‐2 chloride channel protein with characteristic brain MRI features of leukoencephalopathy. We report the first Tunisian patient with clinical features of ClCN‐2‐related leukoencephalopathy. A 54‐year‐old female with a family history of leukemia, male infertility, motor disability, and headaches who initially presented with a tension‐type headache and normal physical examination. At the follow‐up, she developed mild gait ataxia and psycho‐cognitive disturbances. A previously reported homozygous NM_004366.6(CLCN2):c.1709G > A (p.Trp570Ter) stop gained mutation was identified. This report expands the knowledge related to CC2L and highlights the clinical features in affected individuals of African descent

Caractérisation d’un périmètre de reboisement de pinède en vue de proposition des essences les plus appropriées, cas du Jbel Zemzem (Nord-ouest, Maroc)

La dégradation accélérée des forêts est un défi majeur pour les gestionnaires. Le reboisement constitue alors une solution importante pour l’amélioration des services écosystémiques voire la survie des écosystèmes. Comparée à d’autres essences comme l’Eucalyptus, les pins renferment une biodiversité plus élevée. Nous avons étudié la phytodiversité d’un périmètre de reboisement avec quatre espèces et deux variétés de pins (Pinus halepensis, P. pinaster var. maghrebiana et var iberica, P. pinea et P. canariensis) afin de proposer l’essence la plus convenable au reboisement. Sur les 38 relevés floristiques réalisés, 83 espèces ont été recensées appartenant à 34 familles. Les valeurs de l’indice de diversité étaient maximales dans les plantations de P. halepensis et P. pinea et minimales dans celles de P. canariensis. L’ordination multidimensionnel non métrique et la Classification Ascendante Hiérarchique ont montré trois groupes : groupe à P. halepensis et P. pinea, groupe à P. maghrebiana et Quercus suber et groupe à P. iberica et P. canariensis. P. halepensis et P. pinea ont montré un cortège floristique relativement riche mais avec un appauvrissement structurel comparé à la subéraie originale. Il ressort que le reboisement à base de P. maghrebiana et dans une deuxième place P. halepensis améliore la structure des peuplements et présente un potentiel important pour la gestion des reboisements au nord du Maroc

Characterizing spatial structure of Abies marocana forest through point pattern analysis

Aim of study: Understanding small-scale patterns caused by stochastic factors or community interactions driving forest structure and diversity of Moroccan fir Abies marocana Trab. Area of study: Talassemtane fir forest, Talassemtane National Park, Rif Mountains, northern Morocco. Material and methods: Eight plots representative of the structural variability of A. marocana forests were selected, and all tree individuals with diameter at breast height (dbh) ≥2 cm were mapped and measured. We performed four types of spatial point pattern analyses: (1) Univariate analyses to explore the overall trees spatial pattern, (2) bivariate analyses to assess the spatial relationship between juveniles and A. marocana adults, (3) correlation between tree sizes (dbh) and distance between points pairs using the univariate mark correlation function, and (4) random labeling analyses between dominant and suppressed Moroccan fir individuals to assess competition patterns. Main results: We found a strong spatial aggregation of fir individuals and a positive intraspecific association between juveniles and adult trees. However, there were weak but significant distance-dependent effect on tree size and density-dependent effect on suppression pattern. Research highlights: Shade-tolerance, seed dispersal and/or microsite heterogeneity might play important roles in the observed fir patterns. Our results provide a basic knowledge on within-stand Moroccan fir spatial distribution, with implications for adaptive management of these relic forests, and prompting to further research to test advanced hypotheses