Anatomy of peduncle in species of Scrophularia L. (Scrophulariaceae) in Iran

The peduncle anatomy in 35 populations, which belonged to 18 taxa of Scrophularia L., were studied. Am-ong 37 quantitative and qualitative characters related to peduncle anatomy, several traits showed more taxonomic value for taxa delimitation, including presence of palisade parenchyma and the number of its layers, the presence of phloem fiber, the presence of bundle sheath, the presence of lamellar collenchyma at ridge location and the number of its layers, the dimensions of cross section, thickness of vascular bundle, the dimensions of pith parenchyma, thickness of xylem, thickness of parenchymatous part and thickness of lamellar collenchyma at ridge location. Finally, in comparison with the results obtained by Grau (1981), in which 12 groups have been introduced, the current study confirms the validity of 3 groups. However, for the remaining groups, no noticeable concordance was found.