January 11, 2025 | Crop Protection |
Scientists from the University of Florida, USA, conducted a study to investigate the escalating threat of Dragon Fruit Canker (DFC), a fungal disease caused by Neoscytalidium dimidiatum that severely affects dragon fruit production on a global scale. The limited availability of registered fungicides in the U.S., particularly in South Florida, poses challenges for effective DFC control.
The study evaluated the in vitro sensitivity of N. dimidiatum isolates to 13 synthetic and 4 plant-based fungicides and tested their efficacy on detached fruits and in field conditions. Among the synthetic fungicides, fluazinam, fludioxonil, difenoconazole, propiconazole, tebuconazole, and azoxystrobin demonstrated strong inhibition of fungal growth, with EC50 values ranging from 0.01 to 1.48 μg/ml. Plant-based fungicides, including thyme oil and garlic oil, had significantly higher EC50 values and were ineffective in detached fruit assays.
Tebuconazole showed over 95% efficacy in controlling DFC in detached fruits but only 50% efficacy in field trials. Fluazinam emerged as the most effective fungicide in field trials, reducing DFC severity in fruits by 93%, though its effectiveness on stems was lower, with no fungicide exceeding 65% efficacy. This study highlights fluazinam’s potential for DFC control and suggests it should be further considered for registration and broader use in the U.S.
