The Stevia rebandina Bertoni has been introduced and cultivated all over the world and the area of Stevia rebandina
Bertoni cult ivation is growing, The research reports are becoming more and more, but these mainly
concentrate on the morphologic description o f new variet ies[3], the b reeding technologies, the tissue extracting methods of stevioside[5-6], the function testing of different proteins, chromosome and genes[7-9] and its habits of growth[10].