Abstract:
Differentiation among populations of the Iranian
Teucrium polium
L.
was analyzed on
the basis of morphological and phytochemical variab
ility, to evaluate the level and
distribution of diversity among four distant popula
tions from arid, semi-arid, and sub-
humid regions of Fars Province. Morphological analy
sis included 11 characters related to
the plant, leaf, and stem morphology. Analyses of v
ariances and clustering were done to
establish the variability and significance of morph
ological differentiation. The
morphological analysis of plants from the studied p
opulations confirmed that the species
belonged to malacophyllous xeromorphic species and
were distinguished by stable
conservative xeromorphic characteristics. Morpholog
ical variation was correlated with
ecological conditions at the site of origin and the
re was a small difference between the
plants belonging to arid and semi-arid populations
and the sub-humid ones. Chemical
analysis was performed using combination of capilla
ry GC, GC-MS after fractionation on
column chromatography. The chemical composition of
their oil differed qualitatively and
quantitatively between the populations.
β
-Caryophyllene was the major oil compound in
the sub-humid and semi-arid populations, while the
main compound of arid populations
were farnesene-cis-b and linalool. In addition, oil
samples from semi-arid and sub-humid
populations contained
β
-bisabolene (1.6-2.2%), myrcene (0.9-1.1%), bornyl
acetate (0.7-
0.8%), and 3-octanol (0.6-0.8%), which were not det
ected in oil samples from arid
populations. All oil samples, however, were dominat
ed by hydrocarbon compounds. The
relatively low morpho-chemical diversity in the pop
ulations indicates that the
maintenance of their evolutionary potential is at r
isk if population sizes are not
maintained and if there is no protection of the hab
itats.
Keywords:
Essential oil, Medicinal plant, Morphology.
