الملخص

Abstract The effect of growth of two bacterial species Rhizobium leguminosarum biovar vicia and Bacillus subtilis upon growth of five soil species, Fusarium solani, Aspergillus fumigatus, Alternaria alternata, Stemphylum sp., Rhizoctonia solani, was investigated here in rather than the influence of growth of either bacterial species on the other. Both B. subtilis and R. leguminosarum have inhibited growth of total five fungal species with high percentages, on the other hand B. subtilis inhibited R. leguminosarum growth and dominated it. We've obtained different results than those above after adding heavy metals represented with compounds FeCl3, ZnCl2 and CuSO4 with two concentrations each, though some fungi have grown better with the presence of CuSO4, whereas ZnCl2 has inhibited growth of all microorganism species included within this study. Presence of heavy metal in culture medium is not toxic in small quantities, rather it may induce growth and rate of some bioactivities