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.

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Palmyrah (Borassus flabellifer) seed shoot flour has many nutritional values and it contains a high amount of starch. It is widely utilized in the preparation of starch based food products. Since these are seasonal products, most of them are spoiled and wasted due to microbial and insect damage. The aim of this research was to increase the shelf life by using suitable preservation methods. Vacuum packaging, roasting (180 0 C, 10 min), fumigation using phosphine gas (1 gm -3 , 4 days) and addition of preservative (Sodium Metabisulphite, 200ppm) were the treatments done to increase the shelf life of dried seed shoot flour. Microbial stability was compared through variations in Total Plate Count and Yeasts and Molds count for control and all treated seed shoot flour for one year. Chemical (Moisture, Ash and Starch) and functional properties (Water absorption capacity, Bulk density, Foaming capacity, Foam stability and Swelling power) were tested to assess the effect of different treatments. Among the treatments, vacuum packaging contains the less Total Plate Count (6.83±0.01 log CFU/g) and Yeasts and Molds count (3.0±0.1 log CFU/g) after the storage period of one year compared to other treatments. Bulk density was affected by all the treatments applied and compared with control. Fumigation had a significant effect on moisture content (10.76±0.45 %) and Roasting affected the water absorption capacity (219.21 ± 0.42 %) and swelling power (3.82 ± 0.02) of flour positively and forming capacity (54.12 ± 0.04 %) negatively. Based on the results observed vacuum packaging was identified as the best method for preservation of Palmyrah dried seed shoot flour.