الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Phytopathogenic fungi damage many important crops all over the world. Among these fungi, Fusarium sp consider one of the most important known soil borne plant pathogens. Among Fusarium species, F. equiseti caused wilt diseases on various plants. It is a cosmopolitan fungus distributed all over the word. It belongs to the Fusarium incarnatume-F. equiseti species complex.
A total of 22 sp were isolated from the rhizosphere and infected tomato plants. Molecular analysis using genomic DNA sequences were used to identify targeted species. analysis of the obtained F. equiseti st.1& st.2, P. polonicum st.1 & st.2 and Tr. Longibrachiatum. The study of antagonistic activity of the isolated fungi against F.equiseti st.1 and st2 are carried out using dual plate and well assayed methods. The result revealed that Tr. longibrachiatum, P. polonicum st.1 and st.2 are the best antagonist. To find the best condition to get max inhibition, the antifungal activity of these fungi was studied against the 2 strains of F.equiseti by measuring their growth inhibition zone in under the effect of incubation time, culture media, temperature degree and pH. The max inhibition zone occurs after a period of six days, on PD, pH 3 (for Tr. longibrachiatum) and 25°C.
Nano polymers gain attraction in controlling pathogenic fungi that achieving a safe pathway to overcome the chemical fungicides. Chitosan nanoparticles (CNPs) have attracted interest as antifungal for pathogenic fungi due to their unique properties as non-toxicity, low cost, biodegradability and high permeability, Therefore, CNPs were used separately and in consortia with Tr. longibrachiatum, P. polonicum st.1 and st.2 in order to enhance their antifungal activity against the 2 strain of F. equiseti using dual plate method. The maximum inhibition of F.equiseti strains increase with increasing of the conc of CNPs with max inhibition rates of 40.39 % and 66 % respectively at CNPs conc of 0.172 mg/ml. In consortium tests and after 7 days of incubation, all tested mixtures (CNPs with Tr. longibrachiatum, P. polonicum st.1 and P. polonicum st.2, separately) increases the antifungal activity against F.equiseti st.1 and st.2 with max inhibition by mixture of CNPs - Tr. longibrachiatum mixture increases from 60 % to 65.88 % and from 62.74 % to 71.05 % against F. equiseti st.1 and st.2, respectively3.