Antifungal activity of aqueous extract of garlic and oils of carapa and neem on the causal agent of tomato late blight disease
Year: 2025
Type: article
Abstract: This study evaluated the antifungal activity of plant extracts against Phytophthora infestans, the causal agent of tomato late blight. It was conducted in an insect-proof high tunnel using a randomized complete block design with three replicates. Treatments included aqueous garlic extract (0.2 g/mL), carapa oil (12% (v/v)) and neem oil (20% (v/v)), mancozeb 80 WP-based fungicide (5 g/L), and the untreated control. The biopesticides were applied once a week, while the chemical fungicide was applied once a fortnight. Applications were done before or after inoculation with 3×105 zoospores/mL of the pathogen. Recorded disease incidence varied from 50-100% for ancozeb to neem oil for preventive treatments and 100% for curative treatments. There was no significant difference in the severity of symptoms between aqueous garlic extract and mancozeb. The severity index ranged from 13.33 to 17.22% before inoculation to 20.0 to 25.0% after inoculation at the fruiting stage. The severity index of the untreated control was 58.34%. However, the net potential yield after inoculation with mancozeb (8.08 t/ha) was higher than that obtained with aqueous garlic extract (6.56 t/ha), carapa oil (4.95 t/ha), and neem oil (4.66 t/ha) compared to 4.55 t/ha for the untreated control. Hence, aqueous garlic extract can be used in integrated tomato late blight control programs.
Authors: Alahou André Gabaze Gadji, Noupé Diakaria Coulibaly, Eric-Olivier Tienebo, Christian-Landry Ossey, Aya Félicité N’gaza, Mako N’gbesso, Lassina Fondio, Kouabenan Abo
Language: English
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W4408114708