Antifungal activity of purple amomum (Amomum longiligulare T.L. Wu) plant extracts against Fusarium oxysporum Schlecht. and Helminthosporium sativum P. K. & B.

Abstract

Purple amomum (Amomum longiligulare T.L. Wu), which belongs to the monophyletic Zingiberaceae family, is a valuable medicinal plant in Vietnam. The studies on the biological activities of the extracts or essential oils of this species are very limited. So far, there has been no evaluation of the antifungal activity of purple amomum extracts. Fusarium oxysporum Schlecht. and Helminthosporium sativum P. K. & B. fungi which are the causal agent of a wide variety of cereal and many economically important crop species diseases, causing significant losses to agricultural production. The use of plant extracts to control these fungi is an alternative to synthetic fungicides. The attempt of this study was to investigate the antifungal activity of ethanol extracts from different organs of purple amomum against both fungi species. The antifungal effect of purple amomum extracts (including ethanol extract of leaf, seed, rhizome and root, and pseudo-stem) concentrations of 0.05 and 0.10 mg/mL were investigated. Our present study showed that the extracts of purple amomum had different effects on the two fungi species. Extracts of 0.10 mg/mL seed and 0.10 mg/mL leaf in most of the treatments showed the best antifungal effect on both studied fungal species. In all the treatments using seed extract, the lowest indicator of the specific growth rate (m) of the fungi was observed. On the other hand, the antifungal effect of purple amomum extracts on H. sativum fungus appeared to be better than on F. oxysporum fungus. The results of this study open up the prospect of developing new fungicides from purple amomum extracts to treat diseases caused by F. oxysporum and H. sativum fungi in crops.