ASSESSMENT OF THE ANTIFUNGAL ACTIVITY OF Cymbopogan citratus (Lemon grass) LEAF EXTRACT AGAINST SOME PHYTOPATHOGENS

Since the beginning of mankind, nature has been a source of medicinal agent for thousands of years. A plant pathogen is an infectious organism that is capable of causing disease to plants. This research work was aimed at assessing the antifungal activity of Cymbopogan citratus leaf extract on some phytopathogenic fungi isolated from agricultural soils. Aspergillus niger, Aspergillus tamari and Mucor circinelloides were isolated from an agricultural soil.  Aspergillus tamari displayed highest susceptibility to the 50% ethanolic extract of the plant with a mycelial radial growth inhibition measurement of 18.25 ± 0.25 mm while Mucor circinelloides displayed the least susceptibility to the 100% ethanolic extract with a mycelial radial growth inhibition of 45.25 ± 0.25 mm. The results were significantly different from the controls (63.25 ± 0.75 mm, Aspergillus niger; 43.25 ± 1.25 mm, Aspergillus tamari and 63.75 ± 0.75 mm, Mucor circinelloides). In the same vein, the aqueous extract also displayed appreciable antifungal activity. The radial growth inhibition of the aqueous extract ranged from 24.25 ± 0.25 mm (25%, Mucor circinelloides) to 34.50 ± 0.50mm (100%, Aspergillus tamari). These were significantly different from the controls. This Study has shown that lemon grass leaf extract possesses antifungal activities to control phytopathogens, from the result obtained, it can be stated that lemon grass can be exploited as an alternative to chemical fungicides in combating resistance amongst phytopathogens.