Establishment of hairy root cultures of chili peppers (Capsicum annuum) using different explants

Chili peppers (Capsicum annuum L.) are ones of the widespread spices and popularly cultivated plants over the world. The plant belongs to the family Solanaceae. Various in vitro culture techniques have been developed in attempt to study plant characteristics and improve the quality of the crops. However, the rate of progress of studies in Capsicum is relatively slower compared to other members of Solanaceae [1]. In present study, hairy roots culture systems were established in two different pungent cultivars of chilli peppers via Agrobacterium rhizogenes. Two strains of A. rhizogenes, (ATCC 18549 and ATCC 43057), were used for induction of hairy roots in various explants, (hypocotyl, cotyledon, 2 – month – old leaf and 2 – month – old stem), of pungent and low – pungent chilli peppers. The explants were co-cultured with each A. rhizogenes strain in half strength of Murashige & Skoog culture media containing decreasing cefotaxime concentrations. Hairy root initiation was observed earliest in the first week of co-cultivation using hypocotyls, cotyledons, and 2 – month – old stems. The highest frequency of hairy root induction was achieved using ATCC 43057 strain in the hypocotyl of both cultivars. The hairy root induction can be used as alternative culture systems for further studies.