EVALUATION OF FOLIAR DISEASE INCIDENCE AND SEVERITY OF MANGROVES IN UNIVERSITI MALAYSIA TERENGGANU

Abstract

Mangroves are an important ecosystem because of their ecological roles and services, particularly in nutrient cycling and carbon sequestration. However, habitats have declined over the year, mostly due to anthropogenic and natural threats. Mangrove plant diseases caused by pathogenic fungal invasion are poorly described. The status of diseased mangroves remained unknown, primarily in Malaysia. The current study evaluates the disease incidence and severity of mangrove trees in the Universiti Malaysia Terengganu (UMT) campus. This study aimed to determine the dominant type of foliar disease in the UMT campus and identify the most affected mangrove species using Disease Incidence and Disease Severity approach. 30 leaves from each of five mangrove species; Lumnitzera racemosa, Rhizophora apiculata, Hibiscus tiliaceus, Avicennia alba and Sonneratia caseolaris were collected, observed and analysed for the Disease Incidence and Disease Severity. A total of six types of foliar diseases were observed, with leaf blight as the dominant, followed by brown leaf spot, insect graze, grey leaf spot, black leaf spot and anthracnose. Mangrove trees at Jalan Biawak have the highest percentage value of Disease Incidence and Disease Severity compared to mangroves at Pusat Islam UMT. Fungal invasion rate variation could be caused by factors such as temperature, humidity and mangrove species’ resilience toward fungal invasion. Therefore, further study needs to be done to understand this issue better.