Abstract
75 species which belong to 25 genera were collected during this investigation. All of these fungi were previously isolated from Egyptian soils and other sources. The total count and the number of genera and species in the rhizosphere soil of the 5 plants were regularly higher than in nonβrhizosphere soil.
The composition of the rhizosphere fungus flora was considerably influenced by the type and the age of the plant. The most prevalent fungi in the rhizosphere of the test plants after 45, 90, and 150 days were as follows: in Helianthus annuus, Stachybotrys atra and Aspergillus niger; in Chrysanthemum coronarium, Cladosporium herbarum, A. sydowii and Penicillium funiculosum; in Nigella sativa, Fusarium moniliforme and A. sydowii; in Datura innoxia, A. fumigatus and A. terreus; in Hyoscyamus muticus, C. herbarum and A. sydowii; and in soil, P. funiculosum, A. terreus and A. niger. The counts of total fungi and most of the common fungal species, except in the case of Datura innoxia, reached their maxima after 90 days and sharply declined after 150 days.