Somatic Embryogenesis and Long Term High Plant Regeneration from Barley (Hordeum Vulgare L.) Using Picloram

Long term high plant regeneration was obtained from embryogenic callus induced from immature embryo explants of Hordeum vulgare cv RD-57 cultured on MSB medium supplemented with Picloram (2 and 4mg I-1). In the subsequent subcultures different types of calli were recognised which could be distinguished from each other on the basis of their morphology, growth and plant regeneration ability. Best growth and maintenance of embryogenic state of callus was achieved on MSB medium supplemented with Picloram (2 mgl-1). For plant regeneration, embryogenic callus was transferred to hormone free MSB medium. Regenerated plantlets were rooted either on hormone free MSB medium or MSB medium supplemented with IAA (0.5 mgl-1). The regenerated plants were transferred to field conditions where they matured and set seeds. Histological studies of embryogenic callus revealed all the stages of typical somatic embryogenesis. In addition, atypical somatic embryos and secondary somatic embryogenesis was also observed and occasionally de novo shoot morphogenesis was seen in the same cultures.