Identification and characterization of pathogenic fungi causing fungal leaf spot disease on Manilkara Kauki plants

Manilkara kauki, or sawo kecik, is a tropical plant that is susceptible to leaf spot disease caused by pathogenic fungi. The disease reduces the photosynthetic ability of the plant, decreases productivity, and can cause death. The rapid spread of the disease through water, wind, and farm implements, as well as favorable environmental conditions such as high temperature and humidity, make controlling the disease a challenge. This study aims to identify and characterize pathogenic fungi that cause leaf spot disease on Manilkara kauki plants. The method in this study use dependent cultivitation method. The research procedure consists of 3 stages: microscopically observation of leaves, isolation, and identification of pathogenic fungi. Based on the results of this study showed that there are three pathogenic fungi, namely Alternaria alternata, Acromonium strictum, and Fusarium chlamydosporum. A. alternata and A. strictum have white colony characteristics, while F. chlamidosporum is green. Colonies of these fungi invade the epidermal tissue of the leaves, causing necrosis. Fusarium fungi commonly cause root rot. However, in this case fusarium caused necrosis and was found on the leaves. A. strictum causes necrotic symptoms which then enlarge and cause the plant to wilt. Symptoms generally are black soot on the leaf surface, wrinkled leaves, and abnormal leaf shape. A. alternata tends to live as an endophytic and pathogenic fungus while A. strictum and F. chlamydosporum are pathogenic. Therefore, further research efforts are needed to identify molecular traits or characteristics. In order to confirm the nature of the pathogenic fungi of A. alternata.