Distribution and accumulation of alkaloids in Catharanthus roseus G. Don during development.

Pattern of the total alkaloids distribution and accumulation in Catharanthus roseus G. Don was investigated during six different stages of flowering and fruiting. The highest concentration of alkaloids (mg perivine/g dry weight) was found in the roots at the start of flowering and the minimum in the stems during full fruiting stage; the rate of alkaloidal accumulation in the leaves, stems and roots tended to decrease during fruit maturation. The most active stage of alkaloidal biosynthesis was at the start of flowering in all vegetative organs. The maximum dry weights of leaves, stems and roots were obtained during the start of fruiting. The weights of flowers and fruits were relatively very small during different developmental stages. Harvesting Catharanthus roseus should best be carried out at the full-flowering stage to obtain the optimum yield of total alkaloidal content of leaves, stems and roots (as mg perivine/total dry weight of each organ per plant).