Role of Arbuscular Mycorrhizal Fungi in Phytoremediation of Soil Rhizosphere Spiked with Poly Aromatic Hydrocarbons

Results from an innovative approach to improve remediation in the rhizosphere by encouraging healthy plant growth and thus enhancing microbial activity are reported. The effect of arbuscular mycorrhizal fungi (Am) on remediation efficacy of wheat, mungbean and eggplant grown in soil spiked with polyaromatic hydrocarbons (PAH) was assessed in a pot experiment. The results of this study showed that Am inoculation enhanced dissipation amount of PAHs in planted soil, plant uptake PAHs, dissipation amount of PAHs in planted versus unplanted spiked soil and loss of PAHs by the plant-promoted biodegradation. A number of parameters were monitored including plant shoot and root dry weight, plant tissue water content, plant chlorophyll, root lipid content, oxido-reductase enzyme activities in plant and soil rhizosphere and total microbial count in the rhizospheric soil. The observed physiological data indicate that plant growth and tolerance increased with Am, but reduced by PAH. This was reflected by levels of mycorrhizal root colonization which were higher for mungbean, moderate for wheat and low for eggplant. Levels of Am colonization increased on mungbean > wheat > eggplant. This is consistent with the efficacy of plant in dissipation of PAHs in spiked soil. Highly significant positive correlations were shown between of arbuscular formation in root segments (A)) and plant water content, root lipids, peroxidase, catalase polyphenol oxidase and total microbial count in soil rhizosphere as well as PAH dissipation in spiked soil. As consequence of the treatment with Am, the plants provide a greater sink for the contaminants since they are better able to survive and grow.

Ecological survey of opportunistie fungi in ocular infection with special reference to the taximetrie analysis of aspergillus and pencillium species

The importance of opportunistic fungal pathogens in causing ocular infections is emphasized. A study was conducted over a period of two years [1993-1994] to survey the ophthalmic as well as atmospheric fungi in Dakhlia and Qalubia Governorates at lower Egypt. From 500 patients suffering from keratomycosis, 14 species belonging to 12 fungal genera other than Aspergillus and Penicillium were identified. 10 genera comprising 13 fungal species other than Aspergilli and Penicillia were isolated from 250 farm animals showing clinical eye affections. 23 fungal genera including 60 fungal species were recorded as air-spora at the site of sampling. Of these atmospheric fungi, Aspergillus and Penicillium comprises 21 and 13 species respectively. A total of 47 characters and character states for Penicillium and 54 for Aspergillus are selected from morphological and physiological data on 13 and 38 ophthalmic collections described as Penicillium and Aspergillus respectively in this study. The most diverse isolates are become a subject for further taxonomic analysis for grouping the closely related isolates. The identification is judged by using known reference strains isolated from the surrounding atmosphere. Results lead to the suggestion a synoptic key for the etiological agents of corneal ulcer disease belonging to the two genera. The highest Q.S. values in this study indicated on the high affinities between ophthalmic and atmospheric fungi. Exponent of rabbit infection revealed that 55. 2% and 25% of infected rabbits showed positive pathogenicity and precipitin tests respectively. Positive correlation between proteolytic activities of these fungi and their precipitin test as well as their clinical findings were proved