الفهرس 
ACKNOWLEDGEMENTOnly 14 pages are availabe for public view
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Abstract
This study aimed to : Since the chemical pesticides are the most commonly known means of controlling fungal diseases in fields and greenhouses, some major problems threaten to limit the continued use of them Firstly, some fungi develop resistance to a number of chemicals; secondly, some fungicides are not readily biodegradable and tend to persist for years in the environment. The toxic effects of the fungicides on the non-target organisms may also have undesirable changes on the environment. Because of these associated problems, researchers were and still trying to test environmentally safe alternative methods for the disease control by activating the systemic acquired resistance by using compost, bio-agents, antioxidants and their interaction to control Fusarium wilt and root rot disease of cucumber plants caused by Fusarium oxysporum, Fusarium solani, Rhizoctonia solani and Macrophomina phaseolina.
Methods &Results : Samples of cucumber roots suspected to be attacked by root rot and wilt fungi were collected from different areas of Dakahlia and Damietta Governorates of Egypt, isolation and identification of soil-borne fusaria which cause wilt and root rot diseases on cucumber plants.
2- Pathogenicity test showed that F. oxysporum, F. solani, R. solani and M. phaseolina were the most devastating fungi on cucumber roots.
3- The use of salicylic acid at conce ntrations of 2, 4, 6, 8 mM, tartaric acid at (5,10,15, 20 mM) and GAWDA® formulation at (1, 2, 3 and 4 gl-1) significantly reduced the linear growth of F. oxysporum, F. solani, R. solani and M. Phaseolina isolated from cucumber roots. It was also noticed that the reduction in the linear growth was correlated to the increase in concentration of the tested antioxidants4- Results showed that the soaking cucumber seeds in salicylic acid at concentrations of (2, 4, 6, 8 mM), Tartaric acid at concentrations of (5, 10, 15, 20mM) as well as GAWDA® formulation at concentrations (1, 2, 3 and 4 gl-1) for 12 hr. It was found that the optimum values of germination was obtained at 2mM salicylic acid, 10 mM tartaric acid and 1gl-1 GAWDA®.
5-The results also showed that the combination of T. viride, T. hamatum, T. harzinum and G. virens and salicylic acid at 4mM, tartaric acid10mM or GAWDA® formulation 1gl-1did not show adverse effect on the linear growth of Trichoderma spp.
6- The triple combination consists of compost, Trichoderma and antioxidants significantly reduced the percentage of damping-off syndrome of cucumber infected with F. oxysporum, F. solani, R. solani and M. phaseolina. Precisely the combinations of (compost, salicylic acid and T. viride or T. hamatum or T. harzianum or G. virens) or (compost, Tartaric acid and T. harzianum or G. virens) were highly effective on reducing the incidence of damping-off7-Also found that the combination of compost, Trichoderma and antioxidants solely or in their combinations on the content of photosynthetic pigments and the total phenols in cucumber plants infected with F. oxysporum or F. solani or R. solani or M. phaseolina. Results revealed that compost, salicylic acid at 4mM and T. harzianum a significantly increased in the content of photosynthetic pigments and the total phenols.
8-Also in the field experiments, found that the triple formulation consists of compost, Trichoderma and antioxidants significantly reduced the percentage of damping-off syndrome. Precisely the combinations of (compost, salicylic acid and T. viride or T. hamatum or T. harzianum or G. virens) or (compost, Tartaric acid and T. harzianum or G. virens) as well as (compost, GAWDA® formulation plus T. harzianum or G. virens) were highly effective on reducing the incidence of damping-off.
9-Also found that the compost, Trichoderma and antioxidants solely or in their combinations on the content of photosynthetic pigments and the total phenols in leaves of cucumber plants revealed that the triple combination of compost, Salicylic acid at 4mM and T. harzianum a significantly increased in the content of photosynthetic pigments and the total phenols.
10-It was also found that the combination of compost and Salicylic acid at 4 mM in the presence of T. harzianum present a significant increase in the fruit contents of total carbohydrate, ascorbic acid, firmness, total soluble solids, moisture and acidity were reduced.
11- Also found that the triple combination showed a significant increase in the yield, as the number of fruits/plant, fruit length and the fruit diameter was reduced.
12- Also found that the triple combination showed a significant increase in the number of branch /plant, plant weight, shoot weight, shoot length, root weight and root length : Conclusion This research recommend the cucumber growers to use a triple designed formulation of salicylic acid (SA) at 4 mM and T. harzianum for treating cucumber seeds before sawing in soil supplemented with compost at a rate of (2 ton/fed). This tactic proved to be an intelligent method to overcome the incidence of root rot and wilt disease of cucumber and significantly improve the yield and quality of the harvested fruits market competition.