INFLUENCE OF HUMUS FERTILIZATION ON YIELD AND ESSENTIAL OIL ACCUMULATION OF THYMUS × CITRIODORUS

Abstract

Thymus × citriodorus is medicinal, aromatic, essential oil bearing plant, this hybrid can
accumulate commercial important chemical compound – geraniol in it’s essential oil. The aim of
the present study was to evaluate the effect of fertilization with humus on the yield, for parameters
of some leaf epidermal structures,as well as on the quantitative and qualitative composition of
essential oils of T. × citriodorus plants that were grown in an open ground for three years. The
experiment was done in eight experimental plots: four experimental plots were used as control
and other four– for fertilization with humus. The essential oil was isolated by hydrodistillation and
analysed by GC–FID and GC–MS. The results showed that fertilization with humus significantly
positive affected the height of plant, the area covered by plant and the length of inflorescences in
the first experimental year, the density of stomata in both epidermis of leaf in the first and second
experimental years, but significantly negative affected the density of glandular trichomes in lower
epidermis of leaf in the second experimental year. Fertilization with humus did not affect the
percentage and composition of essential oil.