Abstract:Stevioside accumulation in callus cultures derived from Stevia rebaudiana leaf explants was studied during callus growth and differentiation. Increase in stevioside content was positively related to the organization of cells and greening of the cultures, and inversely to the callus growth. Shoot formation in calli was not essential for the synthesis of stevioside. The content of stevioside was highest in slow-growing, compact and green calli either with or without shoot formation. Electron microscope observ...