Ascorbic acid (AsA) has different roles in plant metabolism. Current research was done to evaluate the effect of various concentrations of AsA on growth and micropropagation of Aloe barbadensis Mill., an important medicinal and ornamental herb, for the first time. In this regards, results obtained from applying different concentrations of AsA on variables of aerial part length, length and number of root, number of propagule, brownness of medium, and fresh and dry weights of plants were analyzed after 8 weeks. Control plants showed slower growth in aerial parts than plants treated by AsA. Also, leaves were smaller in control plants. Fresh and dry weights in aerial parts were less in control plants than those of treated with AsA. There was a significant increase in produced numbers of propagules in different treatments compared with control treatment. Average number and length of produced roots in plants treated with AsA were more than those of produced in roots of control plants. In addition, brownness of medium and tissue cultures were reduced in plants treated with AsA, due to existence of different phenolic compounds in these plants. Totally, 80 mg L-1 AsA had the highest effect on induction of growth and development of A. barbadensis Mill. in vitro. تفاصيل المقالة