Effect of two synthetic fungicides on the mycelial growth of Cercospora elaeidis and Curvularia sp., two foliar disease pathogens of oil palm

Oil palm (Elaeis guineensis Jacquin) is a key crop in the Ivorian economy; however, its production is severely constrained by fungal diseases, particularly curvulariosis and cercospora leaf spot in nurseries. This study aimed to evaluate in vitro the antifungal efficacy of two synthetic fungicides applied at different concentrations against major oil palm pathogenic fungi.
The antifungal activity of Antracol 70 WP (propineb, a dithiocarbamate contact fungicide) and Nativo 300 SC (tebuconazole + trifloxystrobin, a mesostemic fungicide) was assessed based on their effects on mycelial growth inhibition. Both fungicides significantly reduced fungal growth in a dose-dependent manner. Complete inhibition of mycelial growth (100%) was achieved at a concentration of 150 ppm for both products. At lower concentrations, Antracol 70 WP exhibited moderate antifungal activity against Curvularia elaeidis; however, its inhibitory effect increased markedly with rising concentrations, leading to total growth suppression beyond a threshold dose.
Overall, the results demonstrate that Antracol 70 WP, despite being a contact fungicide, can fully inhibit fungal growth at sufficiently high concentrations, while Nativo 300 SC provides faster and more effective inhibition due to its systemic properties and dual mode of action. These findings highlight the potential of both fungicides for the management of foliar fungal diseases in oil palm nurseries.