Use of Stomatal Index Determination to Distinguish the Leaves of the Mentha L.

Overview

The Czech Pharmacopoeia 1997 takes over estimation of the stomatal index (S.I.) from the 3 rd editionof the European Pharmacopoeia and lists it in the pharmacognostic methods of drug testing. In theleaves of selected representatives of the Mentha L., values of S.I. were examined in various parts ofthe blade and an investigation was made to find to what extent this value is stable and usable fordistinguishing the individual representatives. In all samples there were cases where the S.I. valuesfound in one leaf significantly differed. The highest probability of distinguishing samples is on thebasis of the values found in the upper margin and the middle centre of the blade. When comparingthe individual samples on the basis of the average S.I. calculated from the values measured in allsix parts of the blade, it is possible to distinguish all samples, except the combinations M. piperita„Prilubskaja – M. aquatica var. bergamotta, M. piperita „Kliment“ – M. piperita var. vulgaris„Mitcham“, and M. piperita „Kliment“ – M. japonica, with the use of I.S.

Key words:
quantitative microscopy – stomatal index – Mentha L.