Transformation of EPSP Synthetase Gene from Allium macrostemon Bunge into Tobacco and Improvement of Resistance in Transgenic Phants Cloning of an RNA-binding Protein Gene from Alfalfa and Expression in Tobacco Cloning and Characterization of a DExD/H box RNA Helicase Gene from Medicago sativa L. Cloning of Chalcone Synthase Gene in Lilium and Expression Analysis of Flower Colour Changes in Transgenic Tobacco