SECONDARY SOMATIC EMBRYOGENESIS IN CROCUS VERNUS (L.) HILL

Abstract

An efficient procedure for secondary somatic embryogenesis of Crocus vernus is described. The primary somatic embryos were induced from the corm explant of C. vernus on Murashige and Skoog (MS) medium supplemented with 1.0 mg l(-1) 2,4-D and 0.5 mg l(-1) TDZ with a mean number of 52 somatic embryos per explant. The effects of medium formulations (Schenk and Hildebrandt (SH), Gamborg (B-5), Chu (N6), Anderson (AM), and MS and 10 and 45 mu mol m(-2) s(-1) photosynthetic photon flux density were studied for primary somatic embryo induction. The greatest number of somatic embryo induction was obtained on the SH medium amended with 1.0 mg l(-1) 2,4-D and 0.5 mg l(-1) TDZ under 10 umol m(-2) s(-1) PPFD. The primary somatic embryos were cultured on SH medium amended with 2iP or BA, in combination with NAA for secondary somatic embryo induction. After 45 days, SH medium fortified with 2.0 mg l(-1) BA and 0.5 mg l(-1) NAA was found to be the best for secondary embryo induction. Secondary somatic embryos were induced on the surface of globular (88.9%) and heart (95.2%) primary somatic embryos. At 1.0 mg l(-1) GA(3) 92.3% embryo maturation and conversion were observed. The highest frequency (100%) of somatic embryo conversion was obtained on SH medium supplemented with 1.0 mg l(-1) GA(3) and 6% (w/v) sucrose.