Abstract:
Palmyrah palm (Borassus flabellifer Linn.) is a highly versatile tree mainly distributed in the
North and Eastern provinces of Sri Lanka. Even though the plant is rarely affected by pathogens
due to its extremely woody nature, some significant abnormalities in plants growing in the
Pungudutivu area in Jaffna Peninsula have been noted recently. The present study aimed to
characterize the abnormality, identify the disease and confirm the possible causative agent. In this
study, the progression and incidence of disease were determined through field visits. A literature
search was conducted to compare the symptoms with other palm varieties. Additionally, the
possibilities for phytoplasma infection were tested with phytoplasma-specific universal primers
using PCR. Initially, the plants showed progressive leaf yellowing and drying from the leaf tip
towards the petiole followed by collapsed spear leaf hanging downward in the crown. Finally, the
crown falls off the trunk. The symptoms are characteristics of the lethal yellowing disease. The
PCR result confirmed the association of phytoplasma with the diseased plants. To our
knowledge, this is the first report from Sri Lanka regarding the lethal yellowing disease in
Palmyrah palm. Since the disease severely affects the plant and spreads rapidly, there is an urgent
need to study the epidemiology of the disease and to find out suitable control measures.
