الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Culture filtrates of nine Drechslera isolates (D. australiensis, D. cactivora, D. cynodontis, D. ellisii, D. hawaiensis, D. maydis, D. neergaardii, D. poae and D. spicifera) used at concentrations of 30, 50 and 70%, were evaluated in vitro against mycelial growth and spore germination of 8 plant pathogenic fungi (Alternaria solani, Botrytis cinerea, Botrytis fabae, Fusarium oxysporum, Fusarium solani, Rhizoctonia solani, Sclerotinia sclerotiorum and Sclerotium cepivorum). Among the tested culture filtrates, only D. cynodontis culture filtrate was highly effective growth inhibitor against all tested fungi, it reducing the fungal growth from 51.1% to 86.7%, and it is the strongest inhibitors to spore germination which inhibited spore germination of all tested fungi by 92% to 98%. Chloroform extract of Drechslera cynodontis culture filtrates was the supreme growth inhibitor against all tested fungi, whereas it inhibited the fungal growth from 66.7% (R. solani) to 88.9% (S. cepivorum) at concentration of 30 mg/ml. Also, chloroform extract was highly effective in suppressing spore germination of all tested fungi at all concentrations. In greenhouse experiments, chloroform extract was the highest effect in controlling the damping-off disease caused by F. solani and S. sclerotiorum on bean (93.4% control). Ethyl acetate extract was the second best (80% control for S. sclerotiorum and 66.7% for R. solani). We isolated two compounds, Dihydrobipolaroxin (1) and Sorokinianin (2) from culture filtrates of Drechslera cynodontis. Compound 1 (Dihydrobipolaroxin) was highly effective growth inhibitor against A. solani, F. oxysporum and S. sclerotiorum (66.7%), while decreased the other fungal growth by 44.4 – 51.1% at concentration of 100 µg/ml. Compound 2 (Sorokinianin) decreased the fungal growth of all tested fungi which ranged from 22.2% (on R. solani) to 61.1% (on F. solani) at concentration of 100 µg/ml. Compound 1 (Dihydrobipolaroxin) highly decreased spore germination of A. solani and F. solani by 80 and 77%, while it inhibited spore germination of the other fungi by 34% to 61% at concentration of 100 µg/ml. Compound 2 (Sorokinianin) was highly effective in suppressing spore germination of F. solani (75%) at concentration of 100 µg/ml, while it inhibited the spore germination of the other four fungi by 43% to 60%.