Al-Qadisiyah Journal For Agriculture Sciences

The study carried out in the eastern Mitidja (Algeria) using groundwater chemistry data is aimed at clarifying the geochemical behavior of the alluvial groundwater as well as assessing the degree of nitrate contamination. The aquifer is characterized by a heterogeneous lithology marked by alternating levels of alluvium, gravel, sand and clay. The chemical facies encountered are: Na - Cl type with 52.7%, Mixed Ca - Mg - Cl type with 29.1%, Mixed Ca - Na - HCO₃ type with 9.1% and Ca – HCO₃ type with 9.1%. The interpretation of the analytical data shows that water mineralization is controlled by many ions Na+, SO42-, Cl-, Ca2+ and HCO3-. The Gibbs diagram suggests that weathering rock is the determining factor in the current chemical composition of groundwater. Agricultural activity is the main source of groundwater contamination by nitrates. Most of the water points tested have NO3 values very close to the critical threshold of 50 mg/l, the world health organization (WHO) drinking water reference value. By comparing this with the "human affected value" of 13 mg/l, 95% of the analyzed waters are considered contaminated. This water degradation is linked to the widespread use of nitrogen fertilizers, agricultural practices and increasing urbanization.

Endophyte microorganisms have great biotechnological interest, with features applicable to different areas and are potentially useful in agriculture. In the current study, the most dominant and representative endophytic fungal species of seven halophytic plants prevalent in the southeastern Algeria, Touggourt, were screened for their ability to produce four extracellular enzymes namely: cellulase, amylase, laccase, and lipase. Zygophyllum album came first by hosting diverse endophytic species among all the tested plants with eight species followed by Tamarix boveana and Limoniastrum guyonianum (46.66%) as well as Phragmites communis with 40% and Haloxylon articulatum and Aeluropus littoralis with 33.33%. Unlike J. effusus, it was the less diverse plant where only three species (20%) were identified. In term of enzymatic activities of the selected fungi, the two species of Chaetomium presented cellulase, amylase and lipase activity. Unlike, Trichoderma harzianum involved in lipase, Ulocladium sp. in cellulase, Bipolaris sp. and Botryostimphylium sp. in Amylase. Unlike, the two species of Chaetomium involved in cellulase, amylase and lipase. On the other hand, no enzyme activity was recorded in the colonies of Fusarium sp.