Proliferation and differentiation from endosperms of Carthamus tinctorius

Abstract

The endosperms of Carthamus tinctorius cv. HUS-305, excised at globular to heart-shaped stages of zygotic embryo development, were cultured on Murashige and Skoog's medium (MS) supplemented with different concentrations of 6-benzylaminopurine (BAP), kinetin, thidiazuron (TDZ), 2,4-dichlorophenoxyacetic acid (2,4-D) or α-naphthalene-acetic acid (NAA). The highest incidence of callusing was on 2,4-D supplemented media. However, embryos differentiated only from the calli developed on media supplemented with BAP, kinetin or TDZ with the last eliciting maximum embryogenic response. The addition of a reduced nitrogen source, casein hydrolysate to MS medium supplemented with BAP and/or NAA, did not stimulate the response. However, adenine sulphate (100 mg dm-3) promoted the induction of somatic embryos. Upon transfer to MS basal medium or the same supplemented with 0.61 µM gibberellic acid (GA3), plumular poles of few embryos elongated resulting in the development of shoots.