European Journal of Biomedical and Pharmaceutical Sciences

EVALUATION OF ANTIFUNGAL ACTIVITY OF SOME ORGANIC COMPOUNDS AGAINST PHYTOPHTHORA MEADII, THE CAUSATIVE AGENT OF FRUIT ROT IN ARECANUT (ARECA CATECHU)

Sameer Patil, Sathisha J. Gonchigar*, S. P. Mohan Kumar, Pallem Chowdappa, Basavaraj Padmasali

ABSTRACT

Arecanut (Areca catechu L) is a most important profitable plantation crop cultivated in Central Western Ghats of Karnataka. Among the various reported diseases in arecanut, fruit rot (koleroga / mahali) is a major devastating disease caused by Phytophthora meadii. It is a major constrain in arecanut production and causes heavy loss in yield. Despite the prophylactic application of both systemic and contact fungicides the incidence and severity of the disease could not be controlled. Recurrence of the disease during the monsoon and subsequent cooler months is due to survival of the fungus as oospores, chlamydospores and mycelium in soil, on fallen nuts, on dried nuts and on inflorescence remaining in the crown. Due to the limitations of conventional fungicides and to search for novel antifungal compounds with persistent and potent inhibitory activity, the present study was undertaken to evaluate the antifungal activity of 16 organic compounds belonging to different groups along with commercial fungicides (Metalaxyl Mz, Bordeaux mixture and Potassium phosphonate product, Biophite) against P. meadii in vitro by radial growth technique. Among them, compounds A (belong to triazole), H (coumarine), I (pyrimidine), M (pyrimidine) & B (benzothiophene) showed significant inhibition of the mycelial growth with an increase in their concentration. Compound A revealed highest inhibitory effect against P.meadii with an EC50 value (10 μg / ml) followed by compounds H & I (30 μg / ml), compound M (50 μg / ml) and Compound B (100 μg / ml). Further, within the five compounds, compound A exhibited promising antifungal activity against P.meadii. However, compared with the commercial fungicides, these compounds exhibit less inhibitory effects. The present study suggests that compound A could act as a potential fungicide to be used for further optimization. Further, this study helps in understanding the molecular mechanism of the antifungal activity of these organic compounds using molecular docking procedure. Also, these findings may be useful for farmers in managing fruit rot disease of arecanut.

Keywords: Arecanut, fruit rot, Phytophthora meadii, Koleroga, Antifungal activity, organic compounds, fungicides.