Biological control of anthracnose disease (Colletotrichum acutatum) by crude leaf extract of fig -

Biological control of anthracnose disease (Colletotrichum acutatum) by crude leaf extract of fig

Fig (Ficus septica Brum.f.) leaf extract has bioactive compounds with antifungal properties due to alkaloid and phenolic compounds. Colletotrichum acutatum is a plant pathogen, which causes the most destructive fungal disease (called anthracnose) in the Solanaceae family, and is triggered by post-bloom fruit drop. The fungus C. acutatum is also the causal agent of the anthracnose disease of chili peppers. Experiments were conducted to measure antifungal activity as well as diffusion to identify the mode of action of fig leaf extract, including a control treatment using sterile distilled water. The minimum concentration inhibition (MIC) to inhibit the growth of C. acutatum on potato dextrose agar (PDA) was 0.9% with inhibition zone diameter (7.25 mm) on the third day of incubation. Based on the in vitro test on PDA and based on the antifungal activity test, the leaf extract of F. septica inhibited the growth of C. acutatum with inhibition zone diameter of 30 mm. Crude leaf extract of F. septica contains bioactive compounds with the antifungal substances which can be safely used as an alternative measure to control anthracnose disease of chili peppers.

Methods of leaf extraction

For extraction of leaf extract, the F. septica leaves were chopped, then dried at room temperature, and after that the dry material was made into powder by means of a blender. F. septica leaf powder (100 grams) was then macerated with 1000 ml of methanol PA (Pro-Analysis) for 72 hours at room temperature and dark place. The filtrate was then macerated again with 1000 ml of methanol as much as two times. The filtrate obtained are combined and then evaporated using a vacuum rotary evaporator (Iwaki, Japan) at 40°C, to obtain a crude extract that was used for further testing.

Antifungal activity test

Antifungal activity test of crude extract of the leaves of F. septica against C. acutatum was done in well diffusion method. The minimum inhibition concentration (MIC) to the growth of C. acutatum on PDA was 0.9% with inhibition zone diameter of 7.25 mm on the third day of incubation. While on treatment with a concentration of 5% could inhibit the growth of fungal pathogen with inhibition zone diameter of 81.39 mm.

Results

Inhibitory activity of partitioned extract

The results indicated that the active biological compounds in the leaf extract of F. septica are antifungal against C. acutatum in the phase of methanol and is polar. Leaf extract of Aegle marmelos inhibited the growth of the fungus C. acutatum with inhibition zone diameter of 22 mm. This treatment effectively reduced and controlled the fungal radial growth on PDA, spore’s formation and biomass formation on PD broth medium with the inhibitory activity ranged from 29.72 to 100%.

Conclusion

The role of F. septica leaf extract in controlling Anthracnose disease caused by pathogen C. acutatum is by affecting the permeability of fungal cell membranes. Disturbance in the permeability of cell membranes caused the cytoplasmic leakage resulting in lysis of the cells, and ultimately the cell growth is inhibited and causes cell death.

Reference:

Sudirga, S.K. and Suprapta, D.N., 2021. Biological control of anthracnose disease (Colletotrichum acutatum) in chili peppers by crude leaf extract of fig (Ficus septica Brum. f.). Sabrao J Breed Genet, 53(1), pp.79-87.