Acomparative anatomical study of the genera Clinopodium L., Hymenocrater Fish.& Mey.and Melissa L. (Lamiaceae) in Kurdistan Region of Iraq

Abstract

Nine taxa of Lamiaceae family including three of the genus Clinopodium (C. vulgare subsp. vulgareL., C. vulgare subsp. arundanum Boiss. ,C. umbrosum (M. B.) C. Koch. and C. congstum Boiss. & Hausskn ex. Boiss., two of Hymenocrater Fish. & Mey. (H,longiflorusBenth. and H. bituminosus Fish & C. A. Mey ) and Melissa officinalis subsp.fficinalis L. , M. officinalis subsp. altissima (SM.) and M. officinalis subsp. inodora (Bornm.)were studied the anatomy of stem, leaf, including petiole and trichomes for all taxa were investigated. Anatomy of stem showed valuable characteristics in the distribution of angular collenchyma, vascular bundles and the thickness of cuticle. Variations were recorded among petiole cross section, vascular strands, in their shapes and number. The anatomical study in cross sections of blade leaves showed that the epidermis were uniserate, plane and consist of one row with shapes of tetra-angled, rectangle, ovate and irregular or polygonal. The mesophyll layers were distinguished in two layers in all studied genera. Detailed study was made for trichomes glandular and non-glandular hairs which showed variation in their types, position, dimension and basal cell number. These variations were important in classification of each species for the studied genera... This study was done for the first time on these taxa in Iraq.