Comparison of manna, phenol, seed germination, morphology and anatomy of Echinops polygamous and E. tenuisecta

Echinops polygamous from Saveh and E. tenuisecta from Sarpol-e Zahab are two medicinal plants belong to the Asteraceae family. The aim of this study was to compare two medicinal plants of Echinops in terms of morphology, anatomical structure, manna trehalo production, seed germination and phenol content. Methods and materials: Morphology by examining the appearance characteristics, anatomical structure by fixing the plant organs, cutting and staining, manna by counting the Larinus cocoons, seed force germination percent, and phenol by Folin Siocaltu's method were studied.

Blue spherical inflorescence, prickly leaves and manna were common in both. Seed germination force of E. polygamous was better. Phenol was abundant in the shoots and inflorescences. The stems of E. polygamous have fallen to the ground and it had dense inflorescences, larger and thicker leaves, and more mana. E. tenuisecta stems were erect with smaller and thinner leaves. The extensive sclerenchyma, in the stem and root of both were observed. Vascular cambium was not observed in the stem. The vascular bundles of stems of E. polygamous were located in a circle and bundles of E. tenuisecta were located in two circle. Root cork cambium was continuous, but vascular cambium was interrupted.

E. polygamous was better in terms of having thicker, larger leaves and fewer spines for insect larvae feeding and forming cocoons.