LARVICIDAL ACTIVITY OF ESSENTIAL OILS OF THYMUS VULGARIS AND ORIGANUM MAJORANA (LAMIACEAE) AGAINST OF THE MALARIA VECTOR ANOPHELES LABRANCHIAE (DIPTERA: CULICIDAE)

Objective: We evaluated the properties of larvicidal activity of essential oils of Thymus vulgaris and Origanum majorana family of Lamiaceae collected at Taounate province in the North East of Morocco, against the larvae of the malaria vector Anopheles labranchiae (Diptera: Culicidae). There are no published data on the effect of these plants on this mosquito, formerly responsible for indigenous malaria.Methods: Biological tests were realized according to a methodology inspired from standard WHO protocol, slightly modified, using the Ethanol as a solvent instead of DMSO. The method consists of making expose the larvae of stages 3 and 4 of the species An. labranchiae to the various concentrations of essential oils. After 24 h of contact, we counted living and dead larvae.Results: The mortality percentages were determined after 24 h. Lethal Concentrations (LC50 and LC90) were calculated and measured. They were respectively of the order of 351.63 µg/ml and 621.34 µg/ml for the essential oil of Thymus vulgari; whereas Origanum majorana were found of the order of LC50 = 107.13 µg/ml and LC90 = 365.9 µg/ml. Conclusion: The results could be useful and interesting for the new application in the production of biocides against the larvae of Anopheles. Also, this information will be needed for the control program and for improving the vector control practices.Keywords: Thymus vulgaris, Origanum majorana, Larvicidal activity, Anopheles labranchiae, Biological tests, North Eastern Morocc

Composition chimique et activité antibactérienne des huiles essentielles de deux plantes aromatiques du centre nord marocain : Thymus vulagris et Thymus satureioïdis

The bacteria are often put in issue in the case of food poisoning and the extensive use of antibacterial chemicals in the medication led to the selection of resistant bacterial strains. Essential oils of medicinal and aromatic plants can be used as an alternative for the treatment of infectious diseases and for the protection of food against any tampering. This study was conducted to examine in Vitro antibacterial activity of the essential oil of Thymus vulgaris and Thymus satureioidis grown in the North-Central of the Morocco, these essential oils are obtained by steam distillation by Clevenger and are tested for pathogenic bacteria: Salmonella sp., Escherichia coli and Staphylococcus aureus, responsible for food-borne diseases in the region of Fes. The chemical composition of the essential oils made by gas chromatography-mass spectrometry. The essential oil of Thymus vulgaris is rich in γ-terpinene (22,25%) and thymol (41,39%). The most abundant chemical compounds in the essential oil of Thymus satureioidis are p-cymene (27,59%) and thymol (14,09%). Two essential oils showed important bactericidal activity on Salmonella sp, Staphylococcus aureus and Escherichia coli.Les bactéries sont le plus souvent mises en cause dans les cas d'intoxications alimentaires et l’usage extensif des agents antibactériens chimiques dans la médication conduit à la sélection de souches bactériennes résistantes. Les huiles essentielles des plantes médicinales et aromatiques peuvent être utilisées comme alternative pour le traitement des maladies infectieuses et pour la protection des aliments contre toute altération. Cette étude a été réalisée dans le but d’examiner in Vitro l’activité antibactérienne de l’huile essentielle du Thymus vulgaris et du Thymus satureioïdis cultivées au centre nord du Maroc, ces huiles essentielles sont obtenues par Hydrodistillation par Clevenger et sont testées sur des bactéries pathogènes: Salmonella sp, Escherichia coli et Staphylococcus aureus, responsables des toxi-infections alimentaires dans la région de Fès. La composition chimique des huiles essentielles a été réalisée par chromatographie en phase gazeuse couplée à la spectrométrie de masse. L’huile essentielle de Thymus vulgaris est riche en γ-terpinène (22,25 %) et en thymol (41,39%). Les composés chimiques les plus abondants dans l’huile essentielle du Thymus satureioïdis sont p-cymène (27,59%) et le thymol (14,09%). Les deux huiles essentielles ont montré une activité bactéricide importante sur Salmonella sp, Staphylococcus aureus et Escherichia coli

Development of Proteomics-Based Fungicides: New Strategies for Environmentally Friendly Control of Fungal Plant Diseases

Proteomics has become one of the most relevant high-throughput technologies. Several approaches have been used for studying, for example, tumor development, biomarker discovery, or microbiology. In this “post-genomic” era, the relevance of these studies has been highlighted as the phenotypes determined by the proteins and not by the genotypes encoding them that is responsible for the final phenotypes. One of the most interesting outcomes of these technologies is the design of new drugs, due to the discovery of new disease factors that may be candidates for new therapeutic targets. To our knowledge, no commercial fungicides have been developed from targeted molecular research, this review will shed some light on future prospects. We will summarize previous research efforts and discuss future innovations, focused on the fight against one of the main agents causing a devastating crops disease, fungal phytopathogens

Bacteria-inducing legume nodules involved in the improvement of plant growth, health and nutrition

Bacteria-inducing legume nodules are known as rhizobia and belong to the class Alphaproteobacteria and Betaproteobacteria. They promote the growth and nutrition of their respective legume hosts through atmospheric nitrogen fixation which takes place in the nodules induced in their roots or stems. In addition, rhizobia have other plant growth-promoting mechanisms, mainly solubilization of phosphate and production of indoleacetic acid, ACC deaminase and siderophores. Some of these mechanisms have been reported for strains of rhizobia which are also able to promote the growth of several nonlegumes, such as cereals, oilseeds and vegetables. Less studied are the mechanisms that have the rhizobia to promote the plant health; however, these bacteria are able to exert biocontrol of some phytopathogens and to induce the plant resistance. In this chapter, we revised the available data about the ability of the legume nodule-inducing bacteria for improving the plant growth, health and nutrition of both legumes and nonlegumes. These data showed that rhizobia meet all the requirements of sustainable agriculture to be used as bio-inoculants allowing the total or partial replacement of chemicals used for fertilization or protection of crops

A transect from a tectonic mélange to an island-arc in the Pan-African of SE Egypt (Wadi Ghadir area)

The Eastern Desert of Egypt, part of the Arabian-Nubian Shielt, is built of ophiolites, ophiolitic melanges, calcalkaline rocks of ensimatic island-arc characteristics and related sediments. It shows the probably best-known example of "modern-type" plate tectonic activity in the Proterozoic. A sequence from ophiolitic melange to mature island arc igneous successions is investigated along a section from the Red Sea (at about 24°45'N) for 20 km to the Wadi Ghadir ophiolite. Along the section imbrication and later faulting are obvious but it is possible to trace individual rock units on both sides of these minor disruptions. It is therefore assumed that the section is complete despite a shortening of 1:10 or 1:20 if compared to modern fore-arcs. The magmatic sequence starts with ophiolites intruded by calcalkaline gabbros and diorites. Several phases of diotite-tonalite-granodioritefollow, separated by mafic dykes. Subsequent, polyphase calcalkaline granite intrusions, again cut by mafic dykes are succeeded by alkaline, post-tectonic granite. Deformation is polyphase, related to melange formation and shearing, affecting, step by step, all of the igneous rocks (except the alkaline granite). Subsequent minor trusts are related to the regional thrusting event, which is followed by open, regional folds. Regional thrusting obviously represents the last stage of crustal thickening, preceeded by magmatic accumulation of increasingly acidic material. Of regional importance is the "facing" of the island arc towards W (subduction towards E), in contrast to earlier views. [...

Geolgoie und tektonische Entwicklung eines pan-afrikanischen Inselbogenkomplexes in SE-Aeqypten (Wadi Ghadir-Gebiet)

With app.SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Larvicidal Activity of Nerium oleander against Larvae West Nile Vector Mosquito Culex pipiens (Diptera: Culicidae)

Background. Outbreaks of the West Nile virus infection were reported in Morocco in 1996, 2003, and 2010. Culex pipiens was strongly suspected as the vector responsible for transmission. In the North center of Morocco, this species has developed resistance to synthetic insecticides. There is an urgent need to find alternatives to the insecticides as natural biocides. Objective. In this work, the insecticidal activity of the extract of the local plant Nerium oleander, which has never been tested before in the North center of Morocco, was studied on larval stages 3 and 4 of Culex pipiens. Methods. Biological tests were realized according to a methodology inspired from standard World Health Organization protocol. The mortality values were determined after 24 h of exposure and LC50 and LC90 values were calculated. Results. The extract had toxic effects on the larvae of culicid mosquitoes. The ethanolic extract of Nerium oleander applied against the larvae of Culex pipiens has given the lethal concentrations LC50 and LC90 in the order of 57.57 mg/mL and 166.35 mg/mL, respectively. Conclusion. This investigation indicates that N. oleander could serve as a potential larvicidal, effective natural biocide against mosquito larvae, particularly Culex pipiens

Phenotypic and genotypic characterizations of rhizobia isolated from root nodules of peanut (Arachis hypogaea L.) grown in Moroccan soils

The phenotypic and genotypic characterization of sixty-two rhizobial isolates obtained from nodules of Arachis hypogaea in north-western Morocco was performed. Their physiological and biochemical properties revealed a great deal of diversity among them. Isolates were classified into two major groups based on the numerical analysis of their phenotypic and genotypic characteristics. Isolates in the first group were alkali- and salt-sensitive, slow or extra-slow growers; they did not use disaccharides as carbon source and varied in the use of amino acids. ARDRA analysis of the 16S rDNA region grouped them together with reference strains belonging to the genus Bradyrhizobium. In the second group, isolates were fast growers, acidsensitive, and alkali- and salt-tolerant; they used both mono and disaccharides as carbon sources, and methionine was the only amino acid they could metabolize as a nitrogen source. ARDRA analysis grouped them with fast-growing reference strains. Both groups exhibited a range of variability in tolerance to heavy metals. The Intergenic Spacer (IGS)-PCR fingerprinting analysis confirmed a high genotypic diversity at the strain level. This characterization provides a basis for the selection of peanut-nodulating rhizobia which may have applications in formulating appropriate inocula for improving peanut crop yield on Moroccan soils, including saline and acidic marginal areas.Peer reviewe