Abstract

In recent decades, there have been concerns of onion bulbs diseases due to microbial infection. Despite advancements in science and technology leading to the discovery and development of several quantitative control strategies, onion rots remain the leading cause of onion spoilage, especially in underdeveloped countries. This study aimed to investigate the antifungal activity of leaf and stem extracts from M. indica and F. platyphylla against fungi associated with rot diseases in onion in Kano state, Nigeria. Phytochemical analysis was conducted using standard methods to investigate the presence of saponin, glycoside, steroid, and phenol, alkaloid and flavonoid in the selected plants. Also the fungi associated with the rot of onion were isolated and identified using microscopic technique for their respective morphological features. This was followed by determination of inhibitory activity of the extracts against the identified fungi. The survey identified Aspergillus niger and Aspergillus flavus as the pathogenic fungi responsible for the rot disease and indicated that M. indica exhibited higher antifungal efficacy compared to F. platyphylla, with M. indica showing significant inhibition of both A. niger and A. flavus. The chloroform extract of M. indica leaf displayed the highest effectiveness, with 94.54% inhibition of A. niger and 93.63% inhibition of A. flavus. Additionally, the methanol extract of M. indica stem bark also exhibited notable antifungal activity. In contrast, F. platyphylla showed moderate to the least effective inhibition against the tested fungi. The findings suggest that both M. indica and F. platyphylla possess antifungal activity against A. niger and A. flavus in vitro.

Keywords:M. indica; F. platyphylla allium cepa; Aspergillus niger; Aspergillus flavus