Studies on preservation method for pure isolates of wheat powdery mildew Leaf Culture and Plantlet Regeneration of Pear (Pyrus) Leaf Culture and Plantlet Regeneration of Pear (Pyrus) Establishment of High2eff ic ien t in Vitro Leaf Regenera tion System in ChineseJujube Establishment of High2eff ic ien t in Vitro Leaf Regenera tion System in ChineseJujube The High-frequency Induction of Adventitious Shoots and Plant Regeneration from Leaf Explants of Phalaenopsis with Added Thidiazuron EFFECT OF AgNO 3 ON APPLE LEAF CULTURE AND ITS RELATION TO ETHYLENE PRODUCTION Studies on plantlet regeneration from the mature leaves of Dioscorea zingiberensis