Essential oil of eaglewood tree: a product of pathogenesis

The essential oil of eaglewood tree (Aquilaria agallocha Roxb.) has been considered to be a pathological product. An investigation was carried out to study the difference in composition of oils obtained from healthy, naturally infected and artificially inoculated eaglewood using GC and GUMS analyses. This investigation showed a marked difference in the oil compositions among the treatments with regards to their quality. Valerianol (3.0%) and tetradecanioc acid (7.1%) contents were recorded higher in the oils of naturally infected plants than in that of healthy ones (0.1% and 6.9%, respectively). Pentadecenoic acid was totally absent in the oils of healthy, whereas it,,vas found in a greater amount (6.8%) in the oil of naturally infected plants. in contrast, dodecanoic acid (3.1%), pentadecanoic acid (6.2%), hexadecanoic acid (31.5%) and octadecanoic acid (4.1%) were found in a higher amount in the oils of healthy plants, while the oils obtained from naturally infected plants contained lower amounts of these components (2.5%, 4.8%, 20.0% and 1.0%, respectively). The oils obtained from the inoculated plants showed almost similar distribution of the components with healthy plants.