The inhibitory effect of ginger and lemongrass plants extracts on the growth of some fungi associated with stored yellow corn grains

Abstract

The current study included testing the effect of the aqueous and alcoholic extracts of the rhizomes of the ginger plant (Zengiber officinal) and the leaves of the lemongrass plant (Cymbopogon citratus) on the germination of local yellow corn grains stored in some local markets in the city of Al-Diwaniyah and studying the effect of four different concentrations of these extracts (10, 20, 30, and 40) mg/ml in the radial growth of some fungi isolated from yellow corn grains. The results showed that there were significant differences in the germination ratios of yellow corn grains for the different concentrations of the extracts in comparison with the control treatment, and there were no significant differences in the germination rates of yellow corn grains at a concentration of 40 mg/ml for the different treatments with the treatment of the fungicide Raxil at a probability level of 5 %. It was found that all the extracts had a significant inhibitory effect on the growth of the fungi tested on Potato Dextrose Agar medium by comparison with the control treatment, and these fungi are: Aspergillus niger, Ulocladium sp., Rhizopus stolonifer and Fusarium graminearum, and the alcoholic extracts of ginger and lemongrass extracts were higher to inhibition of the radial growth of fungi tested in the different treatments, the inhibition ratios were between 73.33-87.12 % in the alcoholic extract treatments for ginger and between 75.15-86.98 % in the alcoholic extract treatments for the lemongrass plant, and the two concentrations were 30 and 40 mg/ml for the alcoholic extracts of the ginger plant and lemongrass has a significant effect similar to that of the fungicide Raxil for all the tested fungi, while it was found that the concentration of 40 mg/ml of the aqueous extracts of ginger and lemongrass was the only concentration that produced a significant effect similar to that of the fungicide Raxil for all tested fungi.