Volumen 7 (2023): Heft 1 (January 2023)

Beneficial Autochthonous Microorganisms (BAMs) are a multi-purpose technology that has already been used in Latin America and Southeast Asia but is still unknown in Africa and particularly Algeria. The aim is to examine the effect of BAMs on agricultural soils and olive fields. The study was carried out in two degraded olive fields located in the Oued Tafna basin west of Tlemcen (The Semi-arid region in Western Algeria). The objective is to evaluate the effectiveness of BAMs on the chemical characteristics of the soils, particularly in terms of organic matter (MO), pH, electrical conductivity (EC), total limestone (CaCO3), moisture, organic carbon (C) and olive production and its weight. Statistical analysis (Independent Test) between all groups (treated and controls) showed a significant difference, in conductivity (EC) where we recorded “0.214±0.03μs /cm “ in treated soils vs. “0.198±0.029μs/cm “ in control soils a different statistical significance was recorded for the other parameters, however, it was observed that there is a relative increase in these parameters in the soils of the treated groups such as carbon (C): “2.85±1.06%” organic matter (MO): “4.91± 1.83%”, “pH=7.81±0.225”, “CaCO₃ 27.76±4.99% and a decrease in humidity “15.11±3.77%” compared to control soils. The results of statistical analyses (Mann-Whitney Test and Suite Test) of olive production showed a clear alternation (every other year) in fruit production in the control group and a positive effect of BAMs on olive production in the treated group, with a slight increase of production (19 kg in 2019 vs. 30 kg in 2020), but without any significant difference regarding the weight of the fruit between the two sessions. However, a highly significant difference “p=0.00<0.001” in fruit weight was noted between the treated groups “3.908g” and “5.70g” and the control ones “4.40g “ and “5.00g” in 2019 and 2020 respectively. The use of MAB is an interesting technique to restore the chemical properties of degraded soils, and increase olive tree production. To achieve more reproducible results (in terms of quantity and quality), sufficient doses of these BAMs and periodicals must be added to provide a good nutritional supplement and reduce farmers’ use of pesticides and mineral fertilizers.

Soil water erosion is a major aspect of landscape degradation in sub-wet to semi-arid Mediterranean environments. This problem has not been dealt with in detail in Algeria although it affects large areas. The objective of this study is to develop a methodology using remote sensing, the digital terrain model (DTM) and geographic information systems (GIS) to map areas with a risk of water erosion within the territory of Saida province and to produce a risk map that can be used as a reference document by the local authority. The presented methodology consists to incorporate three factors controlling the erosion: slope, material friability and land use. The resulting erosion risk map shows five areas of vulnerability to water erosion: very low, low, moderate, high and very high. Areas with high and very high risk of erosion cover more than 20% of the mountainous area and are consistent with our field observations. The methodology presented in this study can be generalized to all areas of the foothills of the Tellian Atlas, where erosion risks pose a threat to urban areas. This model is a tool to help implement a soil conservation plan in order to organise the measures to be applied and ensure sustainable soil management.

The cultivation of fonio in the Western Africa has been greatly hindered by the low amount of rainfall. Crop failure due to drought has been widely reported in Nigeria, which has led to research on different crops with paucity of information on fonio. The present study evaluated six drought genotypes of fonio to determine their physiological and biochemical responses under drought stress conditions. Fonio seeds were planted for a period of 3 weeks and subjected to drought. WUE decreased under drought stress particularly in the P21 genotype, while the RSR significantly increased for all evaluated genotypes. Drought stress seems to enhance the lipid peroxidation and free amino acid activities in the 6 evaluated genotypes, whereas it reduced the proline activities in 4 out of the 6 genotypes. At the early and the late stage, the highest lipid peroxidation was recorded in P25 and P21 respectively. The SOD activities varied at the early and the late stage under drought stress conditions, particularly for the P25, which showed higher level of SOD activities (= 10 folds higher than the control group at the late stage). The activities of CAT and GR for all genotypes studied were not affected by these stressful conditions. However, the APX activity was preferentially reduced in some genotypes, while the remaining ones were unchanged. In conclusion, difference in the physiochemical responses to drought reflects the differences in the ability of the genotypes to withstand varying degrees of drought. The increase in SOD activities might be a frontline defence to counter the increase observed in lipid peroxidation content caused by the reduction in CAT activities under droughtconditionsn.

Perennial species in a mountain grassland where there is high oligotrophy need support for good development. Soil nutrients, either in large amounts or in small quantities, are the driving force in the management of communities of microorganisms that compete and proliferate nutritionally. The symbiosis between vascular plants and fungi in the soil is extraordinary support for perennial species. The roots of the two dominant species in the meadow were harvested after the moment of flowering. They were prepared and stained according to standard methods for evaluating the colonization process. And the process was quantified with the MycoPatt tool. For both species, differentiated fertilization induces similar changes in fungal strategy. But at the level of the formation of the specific structures of the fungi as well as in their development in the cells of the host plants the differences are visible. Maps exported from the MycoPatt tool can be analysed based on strategies or punctually based on color distribution. One can analyse the distribution of each colour (hyphae-blue, arbuscules-red, vesicles-green) as well as the white areas that are represented by parts of the root where the plant does not allow the development of fungi. The use of the MycoPatt tool simplifies the understanding of the symbiotic process and in addition to the multitude of exported indices, it also provides colonization maps that easily show the changes induced by fertilization on the host plants. Thus, being able to predict the best management practice of the whole ecosystem, to sustainably develop grasslands.

This work aims to better to know the floral richness of Tell region (Saida, western of Algeria) particular orchid flora. This inventory was started in 2017-2022; It’s based on random samples, in spring and autumn. The surveys directly targeted open areas (Northern Saida). This inventory revealed the presence of 11 orchids including 2 species, 6 subspecies and 2 varieties. The 11 taxa belong to 5 genera: Anacamptis, Dactylorhiza, Himanthoglossum, Orchis and Ophrys. Some taxa are rare, endemic and are protected (threatened) by the IUCN Red List as a near threatened species and/or are endemic and protected in Algeria, rare species in the Tell region. A stationary precision made it possible to know the distribution area of each identified taxon. Due to anthropogenic threats, a strategy to protect habitats seems very urgent.

Urinary tract infections (UTIs) are currently one of the most important medical practice visits. The spread of antibiotic-resistant bacteria in the community complicates the therapeutic management. The aim of this study is to investigate the bacteria associated with community acquired urinary tract infections (CA-UTIs) and the antibiotic resistance pattern of bacterial isolates during 2021 in Algiers, northern Algeria. A total of 548 urine samples from patients with CA-UTIs symptoms were analyzed. Pure bacterial isolates were identified using morphological and biochemical characteristics, and subjected to antibiogram evaluation using the disk diffusion method. A total 133 out of 548 patients (24.27%) had positive CA-UTIs, mainly affecting women (84.21%). A percentage of 87.22% of isolates were identified as Enterobacteriaceae, which were represented mostly by Escherichia coli (76 isolates), Klebsiella pneumoniae (13 isolates), and Proteus mirabilis (13 isolates). A number of 125 isolates (93.98%) were resistant to at least one antibiotic tested. The results showed the highest antibiotic resistance to ampicillin (92.24%) and amoxicillinclavulanic acid (91.37%), and revealed the most sensitivity to cefotaxime and nitrofurantoin (95.69%) and colistin (93.11%). The results of this study revealed high concerns about CA-UTIs caused by multidrug-resistant Enterobacteriaceae.

The region considered is the South of Tlemcen (Sidi Djilali), in order to high the analysis of the main soil edaphic factors. This study takes into account on one hand the analysis of the different physicochemical characters and on the other hand, the statistical analysis of these factors.

The soils in our study area show some homogeneity. They have a silty-clay texture. With a presence of clay known for its high retention capacity, this texture also includes a significant percentage of sand in front of the other granulometric elements (Sande: 37.5%, Silt: 30.75%, Clays: 31.75%); The pH of the soil is not very alkaline for this region, it varies between 6.69 to 6.89; The rate of organic matter is very low (0.3 and 0.8%), it justifies the low rate of vegetation cover (20 to 30%) and the rather limited restitution to the soil; The limestone rate is average for this region and does not exceed 24.4%; The analyzed soils are unsalted (0.1 and 0.3 mS / cm). Regarding the color of the soil, it differs from one station to another with a tendency to brownish color expressed according to the international color of Munsell (YR). Furthermore, the biostatistical treatment of data collected through the A.C.P. realized with the help of the software "MINITAB 16" concretized with the help of graphs, the correlations which can exist between the different edaphic parameters studied. These biostatistical results allowed us to analyze in a rather precise way the edaphic factors of the southern slope of the Tlemcen region.

Citrus exocortis is a grafting disease caused by Citrus Exocortis Viroid (CEVd). The knowledge of the viroid’s incidence and distribution are necessary to further apply control measures. The objective of this work was to apply the real time PCR assay for the detection of CEVd in samples collected from symptomatic CEVd-infected plants in Mitidja (North Algeria). The assay showed an excellent diagnostic specificity where 38 out of 50 samples showed a positive reaction for CEVd, which revealed the presence of CEVd in citrus orchards with a prevalence of 76%. Consequently, this work offers a quick alternative to conventional methods for the early diagnosis and the prevalence assessment of CEVd.