The variation of the contents of four tropane alkaloids in Anisodus tanguticus Changes of alkaloids in Tibetan medicine Przewalskia tangutica during tissue culture and differentiation of its stem rapid propagation system Progress on Molecular Mechanism of Tropane Alkaloids Synthesis and Plant Bioengineering Research Establishment of the Exogenous Gene Expression System Based on Atropabelladonna Hairy Roots Establishment of the Exogenous Gene Expression System Based on Atropabelladonna Hairy Roots Studies on the Chemical Constituents of Erycibe hainanesis Molecular biology and metabolic engineering of tropane alkaloids biosynthesis Molecular biology and metabolic engineering of tropane alkaloids biosynthesis Metabolic Engineering of Tropane Alkaloid Biosynthesis in Plants Cloning and expression analysis on arginine decarboxylase genes in Atropa belladonna