الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Isolation of fungi from different soybean parts of diseased roots were identified as Fusarium oxysporum, Rhizoctonia solani, Macrophomina phaseolina and Sclerotium rolfsii. Pathogenicity of the isolated fungi on Giza 35 soybean cultivar under greenhouse conditions showed that all tested fungi proved to be pathogenic and caused different degrees of pre and post-emergence damping-off. Results revealed that the highest percentage of pre-emergence damping off caused by R. solani. The highest percentage of post-emergence damping off was recorded by M. phaseolina infection followed by R. solani, F. oxysporum and S. rolfsii. For diseases severity, the highest degree was obtained from plants grown in soil infested with R. solani followed by M. phaseolina, S. rolfsii and F. oxysporum. The infection with F. oxysporum, R. solani, M. phaseolina and S. rolfsii reflected on plant height and weight of Giza 35 cultivar. The highest reduction in plant height and weigh was recoded from plants grown in soil infested with R. solani and the lowest reduction for plants grown in soil infested with F. oxysporum. Three commercial microbial products namely Mycostop®, Bio-ARC® and Bio-ziead® and beside the fungicide Rhizolex were used singly to study their effect on damping-off, root rot and wilt diseases development in soybean in pots. All commercial microbial products and the fungicide decreased damping-off and percentage of infested survival plants and increased healthy survival plants compared with the control treatment. The effect of mustard (Brassica juncea) as a bio-fumigation was evaluated in laboratory, in the pots and in filed against F. oxysporum, R. solani, M. Phaseolina and S. rolfsii infecting soybean plants, mustard seed meal proved to be effective for controlling the causal pathogens of root rot and wilt of soybean plant. Two plant extracts namely rosemary leaves and colocynth fruit with three concentrations ( i.e. 2 , 5 and 10 % of plant extract solution) were added to PDA medium to study their effect on the growth of the pathogenic fungi(F. oxysporum, R. solani, M. phaseolina and S. rolfsii). Rosemary extract at all concentrations gave the highest effect on linear growth in the presence of R. solani at 2, 5 and 10% concentrations. The increasing of concentration for both of the two plant extracts decreased the growth of the tested fungus.