Abstract

LOPEZ-ZAPATA, Silvia Patricia  and  CASTANO-ZAPATA, Jairo. In vitro effect of four fungicides on Colletotrichum gloeosporioides causing anthracnosis on the Red Globe grape variety. Rev. acad. colomb. cienc. exact. fis. nat. [online]. 2020, vol.44, n.172, pp.747-758.  Epub July 05, 2021. ISSN 0370-3908.  https://doi.org/10.18257/raccefyn.1139.

Anthracnose is considered one of the most important diseases of grape crops. In this study, we evaluated the in vitro effect on potato dextrose agar (PDA) of four fungicides: benomyl (Benlate® 50 WP), carbendazim (Belico ® 500 SC), chlorothalonil (Odeon® 720 SC), and dodine (Syllit ® 400 SC) using three concentrations on a Colletotrichum gloeosporioides isolate. This species complex causes anthracnose on the Red Globe grape variety. The concentrations of each fungicide were: benomyl at 0.5, 0.25, and 1 g.L-1; carbendazim at 0.6, 0.3, and 1.2 mL.L-1; chlorothalonil at 2.4, 1.2, and 4.8 mL.L-1, and dodine at 1.6, 0.8, and 3.2 mL.L-1. Evaluated the inhibition of mycelial growth and the sporulation of the fungus. The fungus mycelium exposed to the commercial dose of the fungicides was observed using environmental scanning electron microscopy (ESEM). We used a completely randomized design with 13 treatments and five repetitions. Our results showed a degree of differential efficacy for the four fungicides and their effects were directly proportional to the dose used, benomyl and chlorothalonil being the most efficient in controlling the mycelial growth of the fungus. At the commercial dose, sporulation was inhibited at a higher rate by benomyl showing no statistically significant differences with the other products except chlorothalonil and dodine when the recommended dose was reduced by half. The damage observed by ESEM on the fungus mycelium ratified the effect obtained in vitro, i.e., deformed hyphae and irregular growth. The results of this study, complemented by electron microscopy, are promising for the appropriate selection of the best fungicides for controlling anthracnose on grape fruits, subject to the timely and correct diagnosis of the disease.

Keywords : Fungus; Fungicides; Red Globe.

        · abstract in Spanish     · text in English     · English ( pdf )