Figure 2: a) Pure culture filtrate of fungus Certocystis fimbriata after 30 days of incubation, b) Callus incubated in water (control) after 1 week, c) Callus incubated in potato dextrose broth (control) after 1 week, d) Callus incubated in fungal culture filtrate showing browning and release of phenolics due to toxic effect of filtrate.