Regulation of Indole Alkaloids Synthesis and Related Enzymes During Callus Initiation and Culture of Madagascar Periwinkle Leaves (Catharanthus roseus) Effects of fungal elicitors on accumulation of indole alkaloids in Catharanthus roseus calli The Effects of Dark and Light on Growth and Physiological and Biochemical Characteristics in Cell Culture of Catharanthus roseus (L.)G.Don