الفهرس Only 14 pages are availabe for public view
 |  | from | 120 |  |  |
| | | from | 120 | | |
Abstract
The objectives of this work was to isolate fungi from the phylloplane of the common street tree (ficus nitida L.) in Cairo and (Conocarpus erectus) in Riyadh and from the aerosols around it. Three localities were surveyed in each city (Helwan, Tahrir, Maadi) in Cairo and (Almazar, Alazezia and Alsolimania) in Riyadh throughout the entire year of 2010. A total fungal isolates of 4880 cfu were identified through the entire survey of which 53.6% isolated from Cairo and 46.11% isolated from Riyadh localities. The summer isolates represented 63.54% while the winter isolates represented 36.45%. The aerosol and phylloplane fungal load were nearly the same where 38 species were totally identified of which 28 species from Cairo and 21 from Riyadh. Atomic absorption spectroscopy of the deposited heavy metals in ficus nitida leaf surface revealed the presence of Ni²> Cr²> Cu²> cd²> Pb² arranged in descending concentration in Cairo. In Riyadh they are arranged as Ni²> Pb²>Cu²> Cr²> Cd². The biosorption capacity of the tree predominated fungi for Ni (II) revealed high deposits of metals in the leaf surface of F.nitida and C.erectus. A. giganteus was the most potential biosorbent to Ni (II) followed by A. aegyptiacus then A. fumigatus. Among various physical and chemical pretreatment to the fungal biomasses, NaOH enhances Ni (II) adsorption by the three fungal species. Scanning electron microscopy indicated that the leaf surfaces of F.nitida collected from Cairo covered with heavy mycelial mates and germinated spores, while the leaf surface of C.erectus collected from Riyadh is covered with dormant and desiccated spores with very weak mycelia