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In the present study, eight single-spore strains of Botrytis cinerea were isolated from tomato greenhouses located in Bejaia regions (Northern Algeria). Isolates were molecularly characterized by nine microsatellite markers. Isolates were assigned to B. cinerea and B. pseudocinerea with four isolates of each species. Morphological characterization was established using two cultures media Potato Dextrose Agar and Malt Extract Agar. All isolates inoculated on PDA medium were exclusively Sclerotial and Mycelial on MEA medium. Aggressiveness of both species was similar on tomato leaves and apple fruits. Moreover, B. cinerea isolates were more aggressive than B. pseudocinerea on lettuce leaves. Tomato and lettuce leaves were significantly more susceptible to the both fungi. A negative correlation was established between aggressiveness and morphological type. Phenotypic variability is considered of major importance to explain the epidemiology of the two cryptic species.

Bacteria endophytes are living microorganisms that live inside plant tissues without visible harmful symptoms, providing a mutualistic interaction. In this study, different bacterial endophytic strains were isolated from different plants primed to live in an arid area, namely, the Sahara Desert. Up to 27 of these strains were selected based on their ability to inhibit Botrytis cinerea growth in dual-culture assay and by bacterial volatiles. The results presented in this study show the capacity of most of the bacterial strains to protect Solanum lycopersicum against the pathogenic fungus B. cinerea, under different experimental conditions. Five of these strains induced susceptibility in tomato plants and no callose accumulation upon fungal infection, pointing to callose deposition as a protective mechanism mediated by endophytic bacteria. Moreover, there was a significant correlation between the bacterial strains inducing callose and the level of protection against B. cinerea. On the other hand, hormone production by bacteria does not explain the relationship between protection and the differences between the phenotypic results obtained in vitro and those obtained in plant experiments. Induced resistance is highly specific in the inducer-plant-stress interaction.

Bacteria endophytes are living microorganisms that live inside plant tissues without visible harmful symptoms, providing a mutualistic interaction. In this study, different bacterial endophytic strains were isolated from different plants primed to live in an arid area, namely, the Sahara Desert. Up to 27 of these strains were selected based on their ability to inhibit Botrytis cinerea growth in dual-culture assay and by bacterial volatiles. The results presented in this study show the capacity of most of the bacterial strains to protect Solanum lycopersicum against the pathogenic fungus B. cinerea, under different experimental conditions. Five of these strains induced susceptibility in tomato plants and no callose accumulation upon fungal infection, pointing to callose deposition as a protective mechanism mediated by endophytic bacteria. Moreover, there was a significant correlation between the bacterial strains inducing callose and the level of protection against B. cinerea. On the other hand, hormone production by bacteria does not explain the relationship between protection and the differences between the phenotypic results obtained in vitro and those obtained in plant experiments. Induced resistance is highly specific in the inducer-plant-stress interaction.

45 bacterial isolates from potatoes and wheat rhizospheres near Setif (Algeria) pre-selected for their antagonistic activity against three fungal plant pathogens, two necrotrophic Fusarium solani var. coeruleum and Phytophtora infestans, and a systemic F. oxysporum f. sp. albedinis. Molecular typing of the isolates showed abundance of Bacillus compared to Pseudomonas. Some of the tested strains have shown very high biofilm formation. Among the 24 Gram-positive bacilli screened for four cyclic lipopeptides genes, some isolates harbor two or more genes, while others have a single gene or have none. Four selected isolates were able to regulate the expression of six defense-related genes in Arabidopsis and produce salicylic acid. Upon the features assessed in this study, strain B. amyloliquefaciens A16 was selected for a subsequent use as seed treatment and biocontrol agent in semi-arid region fields. This strain showed important biofilm formation, regulation of Arabidopsis defenses, and harbored three cLPs genes.

Two samples of essential oils from the leaves and cones of wild Tetraclinis articulata (Vahl.) Masters from two different sites in Algeria were isolated by hydrodistillation and investigated by gas chromatography (GC) and GC/mass spectrometry (GC/MS). A total of forty compounds were identified representing 98.6–99.8% of the oils. The main components of the volatile oils were α-pinene (19.8–24.9%) and bornyl acetate (40.2–59.2%) for the leaves, α-pinene (57.5–75%), limonene (10.6–20.9%) and β-myrcene (3.6–10.6%) for the cones. The antioxidant efficiency was tested using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method. In comparison with butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), which were used as positive controls, all samples showed weak activity. The antimicrobial activities of the essential oils were assayed by using the disc diffusion method and agar dilution technique on Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus...

We propose a new aspect of mobility that combines in a same journey and in real time a carpooling service and a traditional multi-modal transportation. This mix allows to improve and complete both services. The main idea of our approach is based on the traditional multi-modal path, in which we try to sequentially substitute some sub-paths of traditional multi-modal transportation to carpooling, in order to decrease the rider’s arrival time at his destination. For this purpose, we first define a closeness estimation between the user’s itinerary and available drivers. This allows to select a subset of potential drivers. We then compute sets of driving quickest paths, and design a substitution process. Finally, among all admissible solutions, we select a best one based on the earliest arrival time. We provide numerical results using geographical maps, real data and public transportation timetabling. Our numerical results show the effectiveness of our system, which improves rider’s arrival time compared to the traditional multi-modal path. The running time of our approach remains reasonable to use real-time transportation application.

This article describes a multi-modal routing problem, which occurs each time a user wants to travel from a point A to a point B, using either ride-sharing or public transportation. The main idea is to start from an itinerary using public transportation, and then substitute part of this itinerary by ride-sharing. We first define a closeness estimation between the user’s itinerary and available drivers. This allows to select a subset of potential drivers. We then compute sets of driving quickest paths, and design a substitution process. Finally, among all admissible solutions, we select the best one based on the earliest arrival time. We provide numerical results using benchmarks based on geographical maps, public transportation timetabling and simulated requests and driving paths. Our numerical experiment shows a running time of a few seconds, suitable for a new real-time transportation application.

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Traditional medicine has been used worldwide for centuries to cure or prevent disease and for male or female contraception. Only a few studies have directly investigated the effects of herbal compounds on spermatozoa. In this study, essential oil from Thymus munbyanus was extracted and its effect on human spermatozoa in vitro was analysed. Gas chromatography and Gas chromatography – mass spectrometry analyses identified 64 components, accounting for 98.9% of the composition of the oil. The principal components were thymol (52.0%), γ-terpinene (11.0%), ρ-cymene (8.5%) and carvacrol (5.2%). Freshly ejaculated spermatozoa was exposed from control individuals to various doses of the essential oil for different time periods, and recorded the vitality, the mean motility, the movement characteristics (computer-aided sperm analysis), the morphology and the ability to undergo protein hyperphosphorylation and acrosomal reaction, which constitute two markers of sperm capacitation and fertilizing ability. In vitro , both the essential oil extracted from T. munbyanus and thymol, the principal compound present in this oil, impaired human sperm motility and its capacity to undergo hyperphosphorylation and acrosome reaction. These compounds may, therefore, be of interest in the field of reproductive biology, as potential anti-spermatic agents.

Ridesharing concerns people that are willing to intelligently ride in order to save money and protect environment. The idea is based on a better use of private car. More precisely, it aims to bring together individuals that share, even partially, a trip. In the recurring ridesharing problem, when an offer is matched with a demand, the driver picks-up the rider at his starting location, drops him off at his ending location and continues to his target location. This approach lacks of flexibility and misses some possible matchings. In this paper, we propose a new ridesharing approach in which a driver and a rider accept to meet in an intermediate starting location and to separate in another intermediate ending location. This allows to reduce both the driver's detour and the total travel cost. We propose exact and heuristic methods to compute meeting points that minimize the total travel cost of the driver and the rider. We analyze their empirical performance on a set of real road networks consisting of up to 3,5 million nodes and 8,7 million edges. Our experimental analysis shows that our heuristics provide efficient performances within short CPU times and improves the recurring ridesharing approach.