Antifungal activity of Acacia tortilis subsp. raddiana tar on Fusarium oxysporum f.sp. albedinis, the cause of Bayoud disease of the date palm in Southwest Algeria

Abstract

Bayoud caused by Fusarium oxysporum f.sp. albedinis (Foa), is the most destructive disease of the date palm (Phoenix dactylifera L.) in Morocco and Algeria and there is no effective control strategy. We found that although Foa isolates vary morphologically, Foa strains can be identified by species-specific primers. PCR analysis revealed that the strains that we isolated from infected date palm rachis were the Bayoud pathogen Foa. We used these strains to evaluate the antifungal activity of tar extracted from Acacia tortilis subsp. raddiana. The A. raddiana tar had a density of 1.15, a refraction index of 1.3850, a pH of 5.2 and a dried matter ratio of 48.75%. The A. raddiana tar effectively inhibited the growth of Foa in vitro with a minimum inhibitory concentration of 3 µg/ml.