The present study investigates the biostimulant effects of 18 Crude Bio-Extracts (CBEs) obtained from Microalgae and cyanobacteria on tomato plant growth, chlorophyll content, nutrient uptake and metabolite profile. Significant root and shoot length improvement (112.65%, 53.70%); was recorded at treatment with Aphanothece sp and C. ellipsoidea cBes respectively. Meanwhile, the highest root and shoot dry weight (DW) (34.81%, 58.69%) were obtained at treatment with Aphanothece sp. the latter also displayed the maximum uptake of nitrogen, phosphorus and potassium, which increased by 185.17%, 119.36% and 78.04% respectively compared with non-treated plants. Principal Component Analysis (PCA) confirmed that Phosphorus and Potassium levels in roots were closely related to enhanced Root length, whereas Nitrogen and chlorophyll b were closely related to Shoot and root DW. Additionally, Gas Chromatography-mass spectrometry (GC-MS) indicated that treatment with CBEs, induced the production of a vast array of metabolites. treated plants recorded higher accumulation of palmitic and stearic acids, which could indicate a stimulation in de novo Lipid synthesis. cBes also triggered the accumulation of pyridine-3-carboxamide (an amide active form of vitamin B3) and Linolenic acid; one of the key precursors in the biosynthetic pathway leading to plant jasmonates. Our results are a first step towards understanding the effects of microalgal extracts on plant physiology and biochemical pathways. further investigations on biochemical fractionation of microalgal extracts and agronomic tests of their purified bioactive compounds could be a useful principal novelty for indepth study of CBE action mechanisms. Other useful tools include; Comparative hormone profiling of treated and non-treated plants accompanied with combined High-throughput plant phenotyping, transcriptomics and metabolomics analysis.www.nature.com/scientificreports www.nature.com/scientificreports/ efficiency 6 . Thus, the use of plant biostimulants is a sustainable alternative strategy to improve crop yield and avert environmental pollution. A plant biostimulant is not a "fertilizer" in the true sense because it's function and role in plant growth is independent of its nutrient content 7 , but it's a material composed of substance(s) and/or microorganisms that stimulate natural processes in plants, leading to enhanced plant growth, nutrient use efficiency, tolerance against abiotic stresses and/or crop quality (European Biostimulant Industry Council EBIC, 2016) 5 . also defined plant biostimulants as; "a formulated product of biological origin that improves plant productivity as a consequence of the novel, or emergent properties of the complex of constituents, and not as a sole consequence of the presence of known essential plant nutrients, plant growth regulators, or plant protective compounds". Among the various categories, seaweeds have so far proven useful for the production of plant growth biostimulants 7-9 . However, far less attention has been focused on Mmicroal...

Investment in SARS-CoV-2 sequencing in Africa over the past year has led to a major increase in the number of sequences generated, now exceeding 100,000 genomes, used to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence domestically, and highlight that local sequencing enables faster turnaround time and more regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and shed light on the distinct dispersal dynamics of Variants of Concern, particularly Alpha, Beta, Delta, and Omicron, on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve, while the continent faces many emerging and re-emerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century.

The COVID-19 pandemic has been ongoing since its onset in late November 2019 in Wuhan, China. Understanding and monitoring the genetic evolution of the virus, its geographical characteristics, and its stability are particularly important for controlling the spread of the disease and especially for the development of a universal vaccine covering all circulating strains. From this perspective, we analyzed 30,983 complete SARS-CoV-2 genomes from 79 countries located in the six continents and collected from 24 December 2019, to 13 May 2020, according to the GISAID database. Our analysis revealed the presence of 3206 variant sites, with a uniform distribution of mutation types in different geographic areas. Remarkably, a low frequency of recurrent mutations has been observed; only 169 mutations (5.27%) had a prevalence greater than 1% of genomes. Nevertheless, fourteen non-synonymous hotspot mutations (>10%) have been identified at different locations along the viral genome; eight in ORF1ab polyprotein (in nsp2, nsp3, transmembrane domain, RdRp, helicase, exonuclease, and endoribonuclease), three in nucleocapsid protein, and one in each of three proteins: Spike, ORF3a, and ORF8. Moreover, 36 non-synonymous mutations were identified in the receptor-binding domain (RBD) of the spike protein with a low prevalence (<1%) across all genomes, of which only four could potentially enhance the binding of the SARS-CoV-2 spike protein to the human ACE2 receptor. These results along with intra-genomic divergence of SARS-CoV-2 could indicate that unlike the influenza virus or HIV viruses, SARS-CoV-2 has a low mutation rate which makes the development of an effective global vaccine very likely.

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The Coronavirus disease 19 pandemic has been ongoing since its onset in late November 2019 in Wuhan, China. To date, the SARS-CoV-2 virus has infected more than 8 million people worldwide and killed over 5% of them. Efforts are being made all over the world to control the spread of the disease and most importantly to develop a vaccine. Understanding the genetic evolution of the virus, its geographic characteristics and stability is particularly important for developing a universal vaccine covering all circulating strains of SARS-CoV-2 and for predicting its efficacy. In this perspective, we analyzed the sequences of 30,983 complete genomes from 80 countries located in six geographical zones (Africa, Asia, Europe, North & South America, and Oceania) isolated from December 24, 2019 to May 13, 2020, and compared them to the reference genome.Our in-depth analysis revealed the presence of 3,206 variant sites compared to the reference Wuhan-Hu-1 genome, with a distribution that is largely uniform over all continents. Remarkably, a low frequency of recurrent mutations was observed; only 182 mutations (5.67%) had a prevalence greater than 1%. Nevertheless, fourteen hotspot mutations (> 10%) were identified at different locations, seven at the ORF1ab gene (in regions coding for nsp2, nsp3, nsp6, nsp12, nsp13, nsp14 and nsp15), three in the nucleocapsid protein, one in the spike protein, one in orf3a, and one in orf8. Moreover, 35 non-synonymous mutations were identified in the receptor-binding domain (RBD) of the spike protein with a low prevalence (<1%) across all genomes, of which only four could potentially enhance the binding of the SARS-CoV-2 spike protein to the human receptor ACE2.These results along with the phylogenetic analysis demonstrate that the virus does not have a significant divergence at the protein level compared to the reference both among and within different geographical areas. Unlike the influenza virus or HIV viruses, the slow rate of mutation of SARS-CoV-2 makes the potential of developing an effective global vaccine very likely.