Micromorphological study of Ziziphora L. (Lamiaceae) in Iran

Ziziphora L. is comprises of four species، Z. tenuior، Z. persica، Z. capitata and nine infra – species in Z. clinopodioides in Iran. Due to the high morphological similarities between some species as Z. persica and Z. tenuior، in this project micro-morphological features of pollen grains and mericarp surface were used to find efficient diagnostic features. Studies were done by use of light microscope and for a better definition between species and exine sculpture patterns; Scanning Microscope (SEM) was used. Most diagnostic characters were apocolpium length، Apocolpium Index (AI)، length of equatorial axis and average diameter of lumens related to bi-reticulate sculpture of pollen grains surface، in studied species separation. Mericarp length and basal condition were of diagnostic importance too. Three studied subspecies of Z. clinopodioides show a close relationship. Results of present study revealed that micro-morphological features of pollen grains and mericarp surface in Ziziphora are of taxonomic value and could be used to define the species relationships and delimitations.