Variation in essential oil composition of Rhododendron tomentosum gathered in limited population (in Eastern Lithuania) ; Pelkinio gailio (Rhododendron tomentosum), surinkto nedideliame plote rytų Lietuvoje, eterinių aliejų įvairovė

Marsh rosemary (Rhododendron tomentosum L. Stokes) H. Harmaja (formerly Ledum palustre) plants were collected at the flowering stage in marshes near Šulnys Lake (Šalčininkai District, Eastern Lithuania) in 2004. Essential oils were prepared by hydrodistillation and analyzed by GC and GC/MS. The major oil constituents were p-cymene (6.2-20.3%), isoascaridol (16.7-24.1%), palustrol (1.2-31.8%) and ledol (5.2-23.4%); and their percentage changed according to the sampling sites. Despite that the plant material was gathered from the limited area, significant compositional variability was observed in the essential oils. Ninety identified (two of them tentatively) compounds comprised up to 97.9% of the oils.