Stability Studies of Some Antifungal Agents Activities Against Selected Phytopathogenic Fungi (Aspergillus niger) Spores

Abstract

Fungi infections have been implicated as one source of yam tuber (genus Dioscorea) spoilage. The effects of temperature, pH and storage duration on antifungal activities of selected combined antifungal agents were investigated using the agar-well diffusion and agar dilution method against Aspergillus niger spores. The test combine antifungal agents are:  Fluconazole/Sodium propionate (1/1µg/ml), Terbinafine Hcl/ Sodium propionate (1/10µg/ml), ketoconazole / Sodium propionate (1/2.5µg/ml), Fluconazole / Griseofulvin (1/1µg/ml), ketoconazole / Griseofulvin(1/2.5µg/ml) and Terbinafine Hcl/ Griseofulvin (1/10µg/ml). The combined antifungal agents activities at 25 - 70 ºC varies while at neutral and alkaline pH (pH 9) the antifungal activities of the chemical agents remained relatively unaffected. There was no significant changes in the antifungal activities of the test combined agents against Aspergillus niger spores at p>0.05 throughout the period of the six months of investigation.  The significant of these finding with relation to stability of the chemical for preserving yam tubers is discussed in this work.

Keywords: Biological control, fungi, Antifungal Agents, Nigeria