Restoration of Triticum aestivum Growth under Salt Stress by Phosphate-Solubilizing Bacterium Isolated from Southern Algeria

Salinity causes significant agricultural losses in many areas in the world. Plant growth promoting bacteria (PGPB) are a promising solution to enhance plant growth and productivity under such stress conditions by different mechanisms, mainly phosphorous solubilization. This study aims to improve wheat seedling growth under salt stress by a halotolerant phosphorous-solubilizing bacterial strain. Soil sample was collected in the south of Algeria (Ghardaia), and bacterial isolation was carried out on nutrient agar (NA) at different NaCl concentrations (300; 600 and 900 mM). The ability of the halotolerant isolates to solubilize inorganic phosphorous at 0; 300; 600 and 900 mM NaCl was determined. The isolate that showed the highest solubilization indexes was selected and identified as Pseudomonas azotoformans. Sterile wheat (Triticum aestivum) seeds were inoculated by this strain and then sown in soil at different NaCl concentrations (0; 100; 200; 300 mM). Different growth parameters were measured after 15 days. The strain showed its highest capacity for phosphorous solubilization (255.152 ± 0.01 µg/mL) at 300 mM NaCl, and for phytate mineralization (0.168 ± 0.002 U/mL) at 100 mM NaCl. The highest amount of soluble phosphorous in the soil was 49.42 ± 0.36 ppm obtained at 100 mM NaCl. Seed germination percentage, shoot and root length and fresh and dry weights were found to be higher in bacterial inoculated seedlings compared to uninoculated ones. According to this study, the use of plant growth promoting bacteria represents an important biotechnological approach to restore phosphorous levels in saline soils and to promote plant growth in salt-affected agricultural land.info:eu-repo/semantics/publishedVersio

Invasive fish disrupt host-pathogen dynamics leading to amphibian declines

Sudden disease outbreaks may not necessarily reflect a recent pathogen introduction but may instead arise from the disruption of a host-pathogen equilibrium. Together with invasive species, emerging pathogens pose significant threats to biodiversity. The dynamics of each stressor have been studied separately, yet rarely when interacting. Using a 40-year dataset, we tested the hypothesis that the introduction of an invasive fish leads to such a disruption, manifested by ranavirosis outbreaks on amphibian hosts. MCP sequencing revealed the historical presence of two major Ranavirus clades, with low prevalence. The introduction of fish was not followed by the emergence of new viruses, but rather by an increase in the prevalence of the strains already present, fitting the ‘endemic pathogen hypothesis’. Two decades after the first die-offs, one amphibian species persists in extremely low numbers, but Ranavirus prevalence is closer to the enzootic phase that preceded the outbreaks. Models show that host population collapse and lack of recovery are best explained by the concerted interaction of Ranavirus and invasive fish. We provide robust evidence that invasive species can impact naïve communities by disrupting the host-pathogen balance, exacerbating health threats. This study emphasizes the importance of exploring the historical interactions between multiple stressors to understand population declines.info:eu-repo/semantics/publishedVersio

Recent progress in marine mycological research in different countries, and prospects for future developments worldwide

Early research on marine fungi was mostly descriptive, with an emphasis on their diversity and taxonomy, especially of those collected at rocky shores on seaweeds and driftwood. Subsequently, further substrata (e.g. salt marsh grasses, marine animals, seagrasses, sea foam, seawater, sediment) and habitats (coral reefs, deep-sea, hydrothermal vents, mangroves, sandy beaches, salt marshes) were explored for marine fungi. In parallel, research areas have broadened from micro-morphology to ultrastructure, ecophysiology, molecular phylogenetics, biogeography, biodeterioration, biodegradation, bioprospecting, genomics, proteomics, transcriptomics and metabolomics. Although marine fungi only constitute a small fraction of the global mycota, new species of marine fungi continue to be described from new hosts/substrata of unexplored locations/habitats, and novel bioactive metabolites have been discovered in the last two decades, warranting a greater collaborative research effort. Marine fungi of Africa, the Americas and Australasia are under-explored, while marine Chytridiomycota and allied taxa, fungi associated with marine animals, the functional roles of fungi in the sea, and the impacts of climate change on marine fungi are some of the topics needing more attention. In this article, currently active marine mycologists from different countries have written on the history and current state of marine fungal research in individual countries highlighting their strength in the subject, and this represents a first step towards a collaborative inter- and transdisciplinary research strategy

Use of drift substrates to characterize marine fungal communities from the west coast of Portugal

This survey reports the occurrence, diversity and similarity of marine fungi associated with five categories of drift substrates (Arundo donax, Phragmites australis, Spartina maritima, "other stems" and driftwood) collected on four sandy beaches of the western coast of Portugal. "Other stems" and driftwood are composite samples with a variety of identified and unidentified pieces of non-woody and woody substrates respectively. Fifty-six taxa were identified, including 38 Ascomycota and 18 anamorphic fungi. Twenty-six taxa were generalists; however several cases of "substrate recurrence" were identified. The very frequent fungi differed among the categories of studied substrates, with the exception of Corollospora maritima, very frequent on four categories. Except for S. maritima, P. australis and driftwood, cases of multiple fungal colonization were rare. S. maritima was the single substrate with five different marine fungi on one sample, as well as with the highest number of very frequent fungi, highest percentage of colonization and average number of fungi per sample. Driftwood presented the highest value of fungal richness (37 taxa) and A. donax the lowest (22 taxa). ANOSIM analysis of similarity showed that all substrates supported different fungal communities with the exception of the pair P. australis/"other stems". The effect of sample size on estimated fungal richness was tested, and the results let us conclude that, although most of the sporadic fungi (<1% occurrence) will be detected only in a very large number of samples, 60 samples of A. donax and "other stems" and 70 samples of all the other substrates may suffice to assess their respective representative marine mycota.publishe

Mengovirus as Process Control Virus in the Monitoring of Genomic RNA and Infectivity of Enteric Viruses in Water Matrices

The present study, developed in the scope of a survey to monitor enteric viruses in natural surface water and drinking water sources, addressed the suitability of mengovirus to assess viral recovery rates at two steps of the water sampling process. In a pilot campaign comprising two samples from each type of water source, when mengovirus was added after the filtration/primary concentration step, the recovery rates of viral RNA were higher than 18% and identical for both water matrices. In a one-year sampling campaign, where mengovirus was present along the whole sample processing (addition in the filtration/primary concentration step), significantly different recovery rates were observed between water matrices: usually higher than 1% in drinking water and under 1% in surface water. The results suggest the first stage of the water sampling process and the type of water matrix are the most influential factors for viral RNA recovery. This study also addressed and evidenced mengovirus replication and titration in Vero E6 cultures and showed infectious mengovirus to be recovered from samples of both types of water matrix. These results anticipate a more comprehensive applicability of mengovirus as a process control virus in the monitoring of viruses in water, extended to viral infectivity

Evaluation of the antiviral activity of an aqueous extract from Solidago virgaurea against Herpes simplex virus type 2

Herpes simplex virus type 2 (HSV-2) is widely distributed through the human population, infecting more than 500 million people globally [1]. Although typically causing mild diseases this virus may be responsible for severe infections, mainly in immunocompromised patients. Currently, there is a number of systemic antiviral agents against herpesvirus, the most commonly used being acyclovir and related drugs. However, long term treatments with these drugs may result in the development of resistance, especially in immunocompromised patients, which leads to a continuous search for new and better therapeutic alternatives [2]. According to the World Health Organization plants are the best sources for obtaining a wide variety of drugs [3]. So, in the last decades many pharmacological and chemical studies have focused on medicinal plants to the discovery of new natural antiviral compounds.Financial support: CESAM (UID/AMB/50017), Centro de Química e Bioquimica (UID/MULTI/00612/2013) and FCT/MEC through national funds and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020.N/

Ocurrence of Ostreopsis in two temperate coastal bays (SW iberia): Insights from the plankton

The benthic genus Ostreopsis contains toxic-bloom forming species and is an important cause of concern in warm-temperate and tropical waters. On the coast of Portugal, NE Atlantic, the occurrence of Ostreopsis cf. siamensis and Ostreopsis cf. ovata has been reported since 2008 and 2011, respectively. This work aims to understand the favorable conditions for high concentrations of Ostreopsis cells in the plankton at two sites, Lagos and Lisbon Bays, located in the South and West coast of Portugal, respectively. This study is based on weekly Ostreopsis abundance data in the plankton, from 2011 to 2017, daily satellite and in situ sea surface temperature (SST), and meteorological and sea state parameters, namely wind stress and significant wave height. The molecular identification of local Ostreopsis spp. is also presented. The maximum cell densities occur between late-summer and autumn. The distribution range of Ostreopsis cf. ovata is restricted to the South coast, while Ostreopsis cf. siamensis has a wider distribution range, being also present on the West coast. In the study period, there was only one occurrence of Ostreopsis spp., in Lagos Bay, with concentrations within the alert phase of monitoring. In Lagos Bay, high Ostreopsis spp. concentrations were related with positive SST anomalies. These high concentrations were often recorded after a period of almost 2-weeks to more than 4-weeks of low sea state ( < 0.6 m), followed by short time events of onshore wind and moderate waves (0.6-1 m). The former conditions are interpreted as favoring bloom development on the substrate and the latter as causing the re-suspension of Ostreopsis cells in the water column. In Lisbon Bay, O. cf. siamensis occurred in the plankton in few occasions and no clear relation could be established with the studied environmental variables. It is here hypothesized that the recent records of O. cf. siamensis in Lisbon Bay may correspond to an early colonization stage of an invasion process. Knowledge gained on Ostreopsis dynamics along the Portuguese coast can be used for both the improvement of benthic harmful algal blooms (BHABs) monitoring in the region and as a basis to design forecasting models.FCTPortuguese Foundation for Science and Technology [SFRH/BPD/121365/2016, SFRH/BD/52560/2014, SFRH/BPD/63106/2009]MARE [UID/MAR/04292/2019]CCMAR [UID/Multi/04326/2013]IPMA [IPMA-BCC-2016-35, SNMB-Monitor/MARE2020

New viruses from Lacerta monticola (Serra da Estrela, Portugal): further evidence for a new group of nucleo-cytoplasmic large deoxyriboviruses

Lizard erythrocytic viruses (LEVs) have previously been described in Lacerta monticola from Serra da Estrela, Portugal. Like other known erythrocytic viruses of heterothermic vertebrates, these viruses have never been adapted to cell cultures and remain uncharacterized at the molecular level. In this study, we made attempts to adapt the virus to cell cultures that resulted instead in the isolation of a previously undetected Ranavirus closely related to FV3. The Ranavirus was subsequently detected by polymerase chain reaction (PCR) in the blood of infected lizards using primers for a conserved portion of the Ranavirus major capsid protein gene. Electron microscopic study of the new Ranavirus disclosed, among other features, the presence of intranuclear viruses that may be related to an unrecognized intranuclear morphogenetic process. Attempts to detect by PCR a portion of the DNA polymerase gene of the LEV in infected lizard blood were successful. The recovered sequence had 65.2/69.4% nt/aa% homology with a previously detected sequence from a snake erythrocytic virus from Florida, which is ultrastructurally different from the studied LEV. These results further support the hypothesis that erythrocytic viruses are related to one another and may represent a new group of nucleo-cytoplasmic large deoxyriboviruses.publishe

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved