Etiology of Anthracnose Disease on Shallots Caused by Colletotrichum gloeosporioides
Anthracnose disease can occur in all growth phases of shallot plants (Allium cepa var. aggregatum); however, disease development and characteristics of the causal agent are not yet known. This research was conducted to study the etiology of anthracnose disease through in vivo and in vitro approach, which includes symptom development, incubation period, and pathogen characteristics. Early symptom of the disease is indicated by the appearance of white spots which then enlarge and finally caused the tissue dies. The typical symptom involves the presence of a concentric orange-brown pattern on the spots with incubation period of 2-4 days. The morphological characteristics of the pathogen colony are white, the conidium is cylindrical, the hyphae are septate. Other character includes the presence of acervulus and setae. Molecular identification of the pathogen showed 99.51% homology with Colletotrichum gloeosporioides accession KT390192.1 from China which originates from tobacco plants.