Effect of Crude Leaf Extracts onColletotrichum gloeosporioides(Penz.) Sacc.

摘要

Colletotrichum gloeosporioides(Penz.) Sacc. is a fungus that causes anthracnose disease in tropical fruit plants, resulting in damages of the fruit plants and low yield and quality of fruits. The use of chemical fungicides is common for management of this disease, but it also results in the development of fungal resistance to the chemicals. Therefore, this study aims toin vitroevaluate the efficacy of 14 crude leaf extracts againstC. gloeosporioides. The results showed thatPiper sarmentosumleaf extracts, using 80% of ethanol, methanol, and chloroform as solvents, were found to have very high antifungal activities. Crude methanol extract ofP. sarmentosumleaves could effectively inhibit the growth of fungal mycelium (100%), followed by crude chloroform extract (81.85%) and 80% ethanol extract (45.50%). Maximum inhibition ofC. gloeosporioidesspore germination could be obtained after application with crude methanol extract ofP. sarmentosumleaves and crude chloroform extract ofMentha cordifolialeaves at 1.25 and 2.5%, respectively. In conclusion, crude extracts ofP. sarmentosumleaves were found to be highly effective for inhibiting bothC. gloeosporioidesmycelium growth and spore germination, and they have a potential as the new natural fungicides for management of anthracnose disease.