الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Sugar beet can be attacked by various diseases which affect its quantity
and quality. Damping-off of seedlings and root rot diseases were
considered among the most destructive diseases which are caused by many
serious soil borne pathogens namely, Sclerotium rolfsii Sacc. The main
goals of the present study to investigate the following point:
Under lab. Conditions:
1. The effect of some metals and herbicide (Topik) on linear growth of
antagonistic fungi Trichoderma harzianum, T. hamatum and the
pathogenic fungus Sclerotium rolfsii.
2. The effect of IC50 of the tested metals on linear growth of the above
mentioned fungi.
3. Effect of some metals and the herbicide on sclrotia formation of
Sclerotium rolfsii.
4. Effect of some metals and the Topik herbicide on the antagonism
between either Trichoderma harzianum or T. hamatum against
Sclerotium rolfsii.
5. Testing the biosaftey of the biocontrol agent.
Under field conditions:
1. Studying the effect of cupper and the herbicide Topik on sugar-beet
damping disease caused by Sclerotium rolfsii.
2. Studying the antagonism between Trichoderma harzianum or T.
hamatum on controlling sugar-beet damping disease.
3. Studying the combined effect of copper and the herbicide Topik on
sugar-beet damping disease .4. Effect of the previous treatments on yield components of sugarbeet,
weight of root under stress of cupper and/or herbicide. The
obtained results could be summarized as follow:
1- Sclerotium rolfsii followed by Fusarium solani then R. solani were the
most prevalent fungi giving the highest frequencies of damping off and
root-rot of sugar beet
2. T. harizianum and T. hamatum were identified as the antagonistic fungi
isolated from the rhizosphere of healthy sugar beet growing in the farm of
Gemmeiza Research station.
3- Both of the Trichoderma isolates did not exudates pectinase enzyme and
proved to be non-pathogenic and could be used safety as a bio-control
agents.
4-Under lab. Conditions, All the metals used showed toxicity to the dual
growth of the tested fungi, nickel followed by cobalt ions were the most
affective metals one on the pathogenic fungus S. rolfsii. While the copper
ion was the most affective one on the radial growth of the antagonistic fungi followed by zinc ion .