الفهرس 
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Abstract
The present study provides a detailed description of the floristic features including: record of the plant species, life-span, life-form spectra and floristic categories of the wild plants associated with the Astragalus spinosus growing naturally in coastal desert represented by western Mediterranean coast and inland desert represented by Wadi Hagoul, it aims at the following objectives: Recognition of the habitat type of the selected species of Astragalus spinosus growing naturally in desert of Egypt. Study the floristic features including: record of species, life-span, life-form spectra and floristic categories of the species in the study area to detect the taxonomic and phytogeographical significance of its floristic components. Quantitative analysis of vegetation structure of the communities associated with the selected species in the habitat type in terms of spatial variations. Analysis of variation in the environmental factors (edaphic) to determine the soil factors controlling the abundance and distribution of the recognized communities in the study area. Evaluation of the economic potentialities of the selected Astragalus spinosus growing naturally in the study area by studying: phytochemical analysis, antimicrobial and antioxidant activity. Floristically, the total number of the recorded plant species surveyed in the present study was 97 species (46 annuals, 2 biennials and 49 perennials) belonging to 89 genera and related to 27 families. Asteraceae comprises 21 species, followed by Fabaceae (11 species), then Brassicaceae (9 species), Poaceae (10 species), Chenopodiaceae (7 species) and Cayophyllaceae (6 species). According to life-forms, the majority of the recorded species were therophytes (48.45%), followed by chamaephytes (23.71%), hemicryptophytes (16.49%) and then nanophanerophytes (7.22%), while the geophytes attained value of 4.12%. Helophytes attained the lowest value of life-forms (1.03%). The vegetation analysis of the plant communities associated with the chosen species in the study area was classified by using multivariate techniques. The application of TWINSPAN classification on the importance values (out of 200) of 97 plant species recorded in 41 stands, led to the recognition of 4 vegetation groups. group A comprises 3 stands dominated by Neurada procumbens (IV= 25.59), group B comprises 5 stands co-dominated by Astragalus spinosus (IV =28.13) and Malva parviflora (IV= 26.50), group C consists of 20 stands co-dominated by Tamarix aphylla (IV=13.30) and Trichodesma africanum (IV=12.35) and group D consists of 13 stands co-dominated by Haloxylon salicornicum (IV =19.18) and Zygophyllum coccinum (IV =16.36). The antioxidant activity by using DPPH radical scavenging activity for an assay of the radical scavenging activity of the methanolic plant extracts of the Astragalus spinosus. Based on the results of IC50, the antioxidant activity of the four parts of two samples follows the sequence shoot ˃ root for coastal and inland sample.In this study, the antimicrobial potential of methanolic extracts of Astragalus spinosus parts (root and shoot) exhibited different inhibitory spectrum activities against four Gram-positive bacteria and three Gram-negative bacteria with different degree.