El-Kharga oasis soils tend to alkaline, very poor in N, P and rich in Ca, Mg, Na, and K. The total algal counts fluctuated, in the study sites (1 6), and ranged between 3.333 colonies/g soil for the plant Hyoscyamus muticus and 4978.3 colonies/g soils for Plantago major. The high percentage of cyanophyta (97.7%) was recorded around Oxalix erniculata, chlorophyta (84.1 5%) around Solanum nigrum and diatoms (53.3%) around Langonychium farctum. On the other hand, the number of total algal species in the study sites ranged between 2 and 1 6 species for Hyoscyamus muticus and Langonychium farctum, respectively. No species belong to chlorophyta and bacillariophyta around the root of Hyoscyamus muticus, Calendula micrantha and Ambrosia martema plants. The only one species encountered high occurrence remark was Pseudoanabaena papilloterminat (Cyanophyta). Treatments of Nostoc carneum with various soaked root extracts of Ambrosia maritima and Hoscyamus muticus caused enhancement of the growth, especially with high concentration of the extract (5%).