Bioassay of natural plant extract for antimicrobial activity in mango anthracnose

Abstract

Anthracnose is one of the most serious diseases of mangoes in many areas where the crop is grown. Anthracnose disease caused by species of Colletotrichum gloeosporioides is the most economically important plant diseases and this disease is responsible for reducing the marketable yield of crop production which 10 % to 80 % reduction in some developing countries. In this study, the mango anthracnose has been treated with the plants extract such as chili, cherry Terengganu and lemongrass at temperature 20 °C, 25 °C and 30 °C. The concentration of the plants extract which are 250 ppm, 1625 ppm and 3000 ppm had been used. These different plant types, temperature and concentration were used to study the effect on antimicrobial activity. The total phenolic content (secondary metabolite) test have been done in investigated the total phenolic content and the concentration observed were 193.8 mg/L for cherry Terengganu leaves extract, 351.6 mg/L for chili leaves extract and 478.0 mg/L for lemongrass leaves extract. The highest concentration for total phenolic content was lemongrass leaves extract. The growth zone of the anthracnose showed less when used lemongrass leaves extract which had given 0.08 mm at temperature 30 °C and concentration 3000 ppm. At temperature 20 °C and 30 °C, the growth zone of anthracnose fungus for all leave plant extracts had shown less than the growth zone of anthracnose when at temperature 25 °C. The observation to measure the growth of the fungus was taken about 8 days for all treatment.