CUCUMBER LEAF EXTRACT INHIBITS DEVELOPMENT OF CUCUMBER ANTHRACNOSE

The cucumber plant sprayed with the supernatant of cucumber leaf extract both of healthy and diseased plants became to be resistant against Colletotrichum orbiculare , the causal agent of cucumber ( Cucumis sativus ) anthracnose. The upper leaves of pre-treated plant showed mild symptom suggesting that the systemic resistance was induced by the treatment of diseased and even healthy leaf extracts. Furthermore, the leaf treated with healthy leaf extract also showed relatively mild symptom suggesting that the leaf extract directly inhibited the fungal infection before the induction of the systemic resistance. The appressorium formation was inhibited in the healthy leaf extract. The healthy cucumber leaf extract may affect doubly on the infection of C. orbiculare and be used as a biological control agent against the cucumber anthracnose and/or other diseases.