Efficiency of Rosemary Rosmarinus Officinalis and Chitosan in Controlling the Damping off Pathogen, Fusarium Spp., Identified Morphologically and Molecularly

Abstract

Results of investigation about the isolates of the pathogenic fungus tested for tomato damping off disease caused by the pathogenic fungus Fusarium spp. showed that all isolates were pathogenic. The isolates HF3, HF4, HF5, and HF7 from the pathogenic fungus Fusarium oxysporum, as well as the isolate HF10 from F. solani had an infection percentage of 100% compared to the control treatment (without the pathogen) (0%). The isolate HF3 was selected for its pathogenicity on tomato seeds in the soil. The laboratory experiment results revealed the pathogenicity of rosemary Rosmarinus officinalis L. oil, chitosan, and the fungicide Pentazol Combi (Metalaxyl + Hymexazole) against the pathogenic fungus F. oxysporum by inhibiting the growth of the fungus in the culture media. Rosemary oil at the concentration of 1% and chitosan at the concentration of 6000 mg.l-1 achieved inhibition of 90.7 and 89.6%, respectively, while the fungicide showed an antagonistic activity getting 89.1% at the concentration of 0.75 ml.l-1.