الفهرس 
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Abstract
The obtained results throughout the present work could be summarized as fallows:
-Sorghum stalk rot disease were occurred wherever sorghum grown in Upper Egypt (Assuit, Sohag and Qena governorates). Since the highest percentage (24.00%) for variety Giza-IS followed by variety Giza- 113 was reported in EI-Hedayat and EI-Zawaida locations in Qena governorate, while in Assuit governorate, the least percentage (4.00%) for variety Giza-IS followed by Giza-I 13 by the same value was obtained in Bani-Helal location.
-Isolation and identification traits showed that the fungus Acremonium strictum was only stalk rotting pathogen.
-Sorghum cultivars were variously responded to Acremonium strictum infection. Cultivar Giza-IS appeared highest susceptibility (60.7% damping off seedlings), while Dorado cv. gave least infection (32% damping off seedlings) under soil infestation. Similarly, cv. Giza-IS expressed highest stalk rot severity (S8%) and Dorado cv. was the least affected (13.3% stalk rot severity) under stalk inoculation by tooth-pick.
-The fungus Acremonium strictum reacted as a non-specific pathogen, since it has ability to infect other plant species such as maize, sugar cane, wheat, pear-millet and okra.
-Laboratory studies revealed that growth of Acremonium strictum was significantly affected by temperature. No growth was recorded at 1 Qt. While maximum was obtained by 35C. Also, growth of Acremonium strictum was affected by chemical inducers, ascorbic acid (AA) and salicylic acid (SA) but not by calcium chloride (CaCI2).
-Bio control agents,i.e., Bacillus subtilis and Trichoderma harzianum showed antagonistic effects towards Acremonium strictum under laboratory conditions. Trichoderma harzianum was more effective to suppress A. strictum growth than Bacillus subtilis. Furthermore, potentiality of the bio control agents was not affected by adding chemical inducers to the growth medium.
-Management experiments gave promising results to control sorghum stalk rot / wilt diseases using chemical inducers and / or bio control products.
-Among chemical inducers, CaCl2 was the most effective to induce resistance in sorghum plants against Acremonium strictum infection
_ Both bio c sorghum da Plant-Guard rot than
_ In addition showed var sorghum da or Plant-G
hogen, r cane,
- Both bio control products, Rhizo-N and Plant-Guard were reduced sorghum damping-off and stalk rot / wilt that caused by A. strictum. Plant-Guard was more effective to control sorghum damping-off / stalk rot than Rhizo-N.
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onium ) and
- In addition, combining chemical inducers with bio control products showed various results. Ascorbic acid gave synergistic effect to control sorghum damping-off / stalk rot when combined with either Rhizo-N or Plant-Guard.
zianum under ;tive to