Document Type : Research Paper
Authors
Abstract
Ephedra shrubs are among native species of Iran and Turan habitat but their anatomical and physical characteristics have not been studied yet. In this study,physical characteristics of wood logs from three ephedra species including Mianeh Ephedra (Ephedra intermedia ),Goats Beard Ephedra (Ephedra major) and Deserts Ephedra or Central Asian Ephedra (Ephedra strobilaceae Bge.) from desert areas of Yazd province were studied. Results shows that Iranian ephedra species similar to the others species show three key anatomical structures: Vessles, Theracheids and, Fibers. The presence of big pits simillar to tracheid pits in some vessel elements support the idea that they are a bridge group linking angiosperms and gymnosperms. Important anatomical features of Iranian ephedras include occurrence of clear and dendroied bodies, elongated and very hetrogenous wooden rayes and latticed vascular valves. Anatomical differences between the three ephedra species provide the key to identify them. There was not any significant difference between average physical characteristics (wet and dry density, shirinkage and swelling).Whereas, average shirinkage and swelling in radial direction was significantly higher than those in tangentiels direction.
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