Abstract

Anti-mycotic activity of the methanolic and aqueous extracts from Algerian Colocynth(Citrullus colocynthis L. Schrad) seed parts were screened in vitro against four important plant pathogenic fungi, namely, Aspergillus flavus, Aspergillus ochraceus, Aspergillus fumigatus and Aspergillus niger, using micro-dilution technique in the broth medium after their phytochemical analysis. The qualitative phytochemical screening of organic extracts revealed the presence of biochemical substances such as alkaloid, flavonoid, steroid and saponins liable for biological activity. Extracts inhibited the mycelial growth of almost all strains of Aspergillus and the results unveiled that the methanol extract was more of antifungal effect than the aqueous extract with minimum fungicidal concentration (MFC) of 15 mg/ml against A. ochraceus, 17.5 mg/ml against A. niger and 25 mg/ml against A. fumigatus. A. flavus proved to be the most resistant strain to the two types of extracts and no activity was recorded. These results showed that the extracts could be considered suitable alternatives to chemical additives for the control of fungal diseases in plants.

Key words: Citrullus colocynthis, methanolic extract, aqueous extract, phytochemical screening, antifungal activity.