الفهرس 
MATERIALS AND METHODSOnly 14 pages are availabe for public view
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Abstract
Twenty three isolates of Fusarium oxysporum, eight isolates of Fusarium solani, two isolates of Verticillium dahliae and four isolates of Rhizoctonia solani were isolated from tomato plants showing wilting and root rot symptoms at different localities in Dakahlia governorate, Egypt. These isolates were varied in their aggressiveness against tomato plants. The influence of varying environmental conditions including temperature, pH, light regime, sealing culture plates with Parafilm (1-10 layers) and type of media on the growth of the pathogenic fungi, F. oxysporum f. sp. lycopersici (isolates 1 and 2), F. solani, V. dahliae and R. solani were evaluated under laboratory conditions in Petri dishes or in liquid culture. The incubation conditions of 250C improved aeration (obtained by not wrapping the culture plates) induced the best growth of all fungi tested. Among the culture media tested, potato dextrose agar (PDA) was the best medium for the growth of all fungi tested except for F. oxysporum f. sp. lycopersici (isolate 1) which grew best on lima bean agar. The continuous light induced the best growth for F. oxysporum f. sp. lycopersici (isolate 2), F. solani and R. solani. However, F. oxysporum f. sp. lycopersici (isolate 1) grew best under continuous darkness while diurnal light was the best for V. dahliae growth. In general, pH 8 (initial level) promoted the best growth of all fungi tested (isolate 2 of F. oxysporum f. sp. lycopersici, F. solani, V. dahliae and R. solani) except for F .oxysporum f. sp. lycopersici (isolate 1) which was best grown at pH 9 (initial level). Laboratory and Greenhouse experiments were conducted to evaluate T. viride, T. harzianum, Bacillus subtilis, Pseudomonas fluorescens as well as essential oils as clove and mint for the controls of wilt and root rot of tomato, caused by Fusarium oxysporum f. sp. lycopersici, Fusarium solani, Verticillium dahliae and Rhizoctonia solani. Tomato seedlings cv. ”Super marmand” were transplanted into soil amended or nonamended (as a control treatment) with the bioagents. All bioagents significantly inhibited mycelial growth of pathogenic fungi i.e. F. oxysporum f. sp. lycopersici, F. solani, V. dahliae and R. solani in at laboratory level compared to the controls, significant decreases in disease incidence were obtained with treatment of T. viride, T. harzianum, Bacillus subtilis, Pseudomonas fluorescens, clove and mint. In addition, using all bioagents increased significantly photosynthetic pigment content, tomato plant growth and yield