Abstract:

This research was intended to isolate, purify, and identify the pathogens which cause ginger rotting during
storage, to screen essential oils for controlling the pathogenic isolates, and to test their effectiveness. In this work, ljw2 and
ljr4 were identified as pathogens through isolation, purification, and pathogenicity tests. The results of 18S rDNA sequence
analysis showed that these fungi belonged to the genera Fusarium and Mortierella. Six essential oils, based on the pathogen
genera, were investigated for their activity to control these pathogens. As results, cinnamon and thyme oil showed complete
inhibitory effect on all pathogens at a concentration of 2 000 μL/L. Cinnamon oil showed higher antifungal activity in the
drug sensitivity test. The minimal inhibitory concentrations (MIC) of cinnamon oil against these two pathogens were 64 and
32 μL/L, respectively. The minimal fungicidal concentrations of cinnamon oil against the pathogens were 125 and 500 μL/L,
respectively. Compared with untreated samples, the infection rates of fumigation treatment samples declined by 59.33% (ljr4)
and 47.33% (ljw2), respectively. Cinnamon oil seems to be a promising potential fumigant.

Key words: Fusarium, Mortierella, 18S rDNA, cinnamon oil, antibacterial effect