Inhibitory Effect of Some Plants of Western Ghats of Karnataka against Colletotrichum capsici

Abstract

Anthracnose is a serious disease of chilli which results in major crop loss. Species of Colletotrichum are the causative agents of chilli anthracnose. In the present study, we investigated the inhibitory effect of a total of 50 extracts from 35 plants (belonging to 23 botanical families) of Western Ghats of Shivamogga district, Karnataka, India. The powdered plant materials were extracted using methanol. The methanol extracts were screened for antifungal activity by Poisoned food technique against Colletotrichum capsici isolated from anthracnose of chilli. All extracts were effective in inhibiting the growth of C. capsici but to a varied extent (16 to 74% inhibition). The mycelial growth of fungus was found to be reduced on poisoned plates when compared to control plate. Marked inhibitory efficacy was observed in case of leaf extract of Maesa indica (74.19%) followed by leaf extract of Pimenta dioica (70.96%). Least inhibition of the fungus was shown by leaf extract of Persea macrantha (16.13%). The extent of inhibition of the fungus by other extracts ranged between 20 to 70%. In conclusion, the plants selected in this study appear promising as natural antifungal agents. Further field studies are to be conducted to determine the possible application of these plants in the control of chilli anthracnose.

Keywords: Western Ghats; Antifungal activity; Poisoned food technique; Colletotrichum capsici; Anthracnose of chilli