Analysis of Cellular Characteristics of Cork and Cellular Structure from Two Types of Quercus variabilis Effect of nitrogen forms on berberine, jatrorrhizine and palmatine content in corktree seedlings Effects of light intensity on the contents of three main alkaloids in amur corktree seedlings Comparative Studies on Histology of Rhizoma Arisaematis and Pinelliae The Microstructure of Cork from Quercus variabilis Growth and Characteristics of Cork from Two Types of Quercus variabilis in North Slopes Qinling Mountains The Structure and Antifungal Functions of Vegetative Propagation Corm of Gastrodia elata Effects of three Arbuscular Mycorrhizas on Different Provenances of Amur Cork Seedings Effects of water stress on berberine, jatrorrhizine and palmatine contents in amur corktree seedlings Effects of color films on the contents of three main alkaloids in amur corktree seedlings STUDY ON THE NUTRIENT ELEMENT CYCLE IN THREE MEDICINE PLANTATION ECOSYSTEMS