Characterization and Morphology of Botryosphaeria Ribis Causing Canker in Eucalyptus

Eucalyptus species are widely cultivated in India for their rapid growth and economic value in reforestation and timber industries. However, their productivity is increasingly threatened by fungal pathogens, among which Botryosphaeria ribis has emerged as a significant causal agent of stem cankerand gummosis. This paper documents the first confirmed report of Botryosphaeria canker in Eucalyptus plantations of Telangana, India. Field surveys and pathogen isolation techniques were employed to assess disease symptoms, collect infected samples, and isolate the causal organism. The characteristic symptoms include sunken, reddish-purple cankers on stems and twigs, gummosis, and necrotic lesions on young shoots and leaf mid-veins. The pathogen was isolated, identified morphologically, and confirmed as Botryosphaeria ribis based on Koch’s postulates. Detailed morphological features, including pycnidia and conidia structure, are described. The findings underscore the need for heightened disease surveillance, early diagnosis, and management strategies to safeguard Eucalyptus plantations from this emerging threat.