الفهرس 
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Abstract
Eightyseven seed samples of wheat provided by the Central Administration for Seed (Ministry of Agriculture & Land Reclamation, Giza, Egypt) and twentyeight seed samples from bulk shipments of wheat imported from Argentina, Australia, France, and United Stated of America were used in this investigation. Standard blotter method recommended by (ISTA, 1999) as well as soaked blotters in NaOH or KOH at three pH levels 7, 12 and 13 were appliedd to detect seedborne fungi of wheat. Results revealed the detection of fifteen genera of fungi namely: Alternaria alternata, Aspergillus flavus, Aspergillus niger, Bipolaris hawaiiensis, Bipolaris sorokinana, Cephalosporium gramineum, Cladosporium sp., Epicoccum sp., Penicillium sp., Fusarium culmorum, Fusarium moniliforme, Fusarium semitectum, Fusarium graminearum, Stemphylium sp. and Verticillium spp. were isolated. When blotters were soaked in NaOH (pH 12) or KOH (pH 13) and used for plating wheat seeds, the two low growing fungi i.e. Cephalosporium gramineum and Verticillium spp. were identified from seed surface using X40 of the stereoscopic microscope. This was impossible before due to the fast growth of the saprophytes (Aspergillus spp. and Penicillium spp.). On the other hand, pH 12 & 13 treatments enhanced the sporulation of Cephalosporium gramineum and Verticillium spp. Data show that there were no differences between the cultivars [Sakha 93, Gemmeza 7, Giza 170 and Sids 1] in the transmission of Cephalosporium gramineum from seed to seed. The fungus was found in the examined parts including crown and subcrown, first node, last node, stem, spike and seed, respectively. The results proved that Cephalosporium gramineum has a systemic vascular pathway in the inoculated plants. GWDAH is a formulation consisting of a number of environmentallysafe substances including antioxidants and salts which enhance ATP production in the cell (the main source of energy in the cell). This formulation needs the rules of the agricultural biodynamic and used at low level of concentration. It significantly delays and/or prevents the oxidation of the substrate. However, it is designed to be used at concentrations of 3000 ppm. Bioassay of GWDAH formulation was followed by testing its effect on growth of the following fungi: Fusarium culmurum, Fusarium graminearum, Bipolaris sorokinana, Cephalosporium gramineum and Ustilago tritici. GWDAH Formulation was inhibited the growth of all tested fungi at concentration of 3000 ppm followed by salicylic acid and benzoic acid (6000 ppm) comparing with check. GWDAH formulation treatment increased shoot length by 14% and fresh weight by 32% in 21dayold seedlings. In addion, total chlortophyll increased by 5%, caroteniod by 12%, total phenol by 26% and total antioxidant activity by 27%. On the other hand, the treatment increased root diameter, stele diameter, and no. of metaxylem vessels, as well as increases the thickness of the outer epidermal cell wall. Exodermis cell wall and metaxylum vessel wall thickness were also increased in GWDAHtreated roots. GWDAH treatment also increased the proportion of actively conducting vessels. This is a beneficial way for compensating damaged or occluded vessels produced by fungi, thereby enhancing plant resistance GWDAH formulation and Plant GrowthPromoting Rhizobacteria (PGPR) were tested as a promising formula for controlling seedling blight; foot root rot and common root rot diseases. Wheat seeds were soaking in the GWDAH formulation [3000 ppm] for 12 h in the dark at 25oC and then divided to two lots, one lot was coated with Plant GrowthPromoting Rhizobacteria (PGPR) and the other lot was left as check planted in pots infested with Fusarium culmurum, Fusarium graminearum, and Bipolaris sorokinana. Results showed that, GWDAH formulation or/and Bacillus polymyxa were highly effective in reducing the disease incidence caused by Fusarium culmurum, Fusarium graminearum and Bipolaris sorokinana. In the Check treatment, disease incidence was detected at 43% in plants grown in infested soil with Fusarium graminearum or Bipolaris sorokinana and 65% in Fusarium culmurum infested soil. GWDAH formulation treatment alone or in combination with Plant GrowthPromoting Rhizobacteria (PGPR) [Bacillus polymyxa] decreased the disease incidence to be 3% in Fusarium graminearum, infection 7% in Fusarium culmurum and 10% in Bipolaris sorokinan