Control of anthracnose disease of banana with inorganic salts

Abstract

Effects of sodium bicarbonate, calcium propionate, sodium metabisulfite, potassium carbonate and ammonium carbonate against mycelial growth of Colletotrichum gloeosporioides were evaluated in a in-vitro study. Sodium metabisulfite is found to be the most effective salt that exhibited fungicidal activity at the lowest concentration of 0.06% compared to the other salts. Post-harvest application of sodium metabisulfite to control infection of anthracnose on bananas caused by C. gloeosporioides was evaluated in a in-vivo study. The effectiveness of the treatments were assessed by evaluating their impact on physical-chemical parameters of fruits such as firmness, hue angle, chroma, total titratable acidity (TT A), total soluble solid (TSS), pH, vitamin C content, diameter of lesion and incidence. The bananas subjected to curative treatment using 2% sodium metabisulfite showed less fungus infection and greater flesh firmness as compared to other treatments. No significant difference was observed in the hue angles of bananas subjected to curative treatment and bananas injured before being dipped into salt with control. In addition, there were no significant differences in the chroma, TT A and vitamin C content among all treatments and control. However, the bananas subjected to protective treatment and untreated bananas showed higher value in TSS and pH compared to bananas subjected to curative treatment. This result suggests that curative treatment using sodium metabisulfite could provide a significant level of protection on bananas.