الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
The following study screened the antifungal activity of twenty wild plant against three phytopathogenic fungi (Fusarium oxysporum, Fusarium solani and Rhizoctonia solani). Antifungal activity of plant extracts was performed using poison food technique. The most effective plants were subjected to further extraction using polar solvents for studying their antifungal activity in vitro and in vivo, Minimum inhibition concentration, Minimum fungicidal concentration and their mode of action. Plants with the highest antifungal activity were used to synthesize silver nanoparticles and to test their antifungal activity in vitro and in vivo. Furthermore, qualitative phytochemical screening and quantitative determination of phenolic acids and flavonoids using HPLC technique was performed to the most effective plants. Results indicated that plant extracts have a variant degree of antifungal activity against tested fungi. Artemisia herb alba, Pulicaria undulata, Fagonia arabica and Gymnocarpos decandrus were the most effective plants. The minimum inhibitory concentrations (MICs) of the plant extracts ranged between (0.75–20) mg/ml while the minimum fungicidal concentrations ranged between (2.5–20) mg/ml. Results indicated inhibition effect of plant extracts on extracellular enzyme (protease and catalase) and their ability to cause malformations in the morphology of Fusarium oxysporum conidia and hyphae. Artemisia herb alba and pulicaria undulata succeeded in reduction of silver into silver nanoparticles that was confirmed by UV – visible absorption spectra, X- ray Diffractometer and Transmition electron microscope (TEM). Moreover, They were able to inhibit fungal growth on petri plates. Plant extracts and synthesized AgNPs were effective in protecting Vicia faba L. seeds from infection with Fusarium solani. They reduced damping off incidence in Vicia faba L. seeds in pre emergence and post emergence stages. Artemisia herb alba extract reduced damping off in pre –mergence and post emergence stages by 55.5 %and 75% respectively followed by P. undulata extract that reduced disease incidence by (44.45% and 75%), G. decandrus(33.35 and 62.5%), P. undulata
AgNPs by( 33.35 %and 50%) and A. herb alba AgNPs by 22.23% and 37.5% respectively. Phytochemical screening of active plants indicated their high content with phenolic, flavonoids, saponins, tannins and alkaloids. Further quantitative detection of phenolic acids and flavonoids in Artemisia herb alba, Pulicaria undulata and Gymnocarpos decandrus using HPLC technique indicated the presence of catechol, caffeine, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, benzoic acid, ellagic acid, o-coumaric, salicylic acid, myricetin, quercitin, and kampherol as the main components.
Key words: Antifungal activity, Phytochemical screening, phytopathogenic fungi, Wild plants.