Indirect somatic embryogenesis and shoot organogenesis from cotyledonary leaf segments of Digitalis lamarckii Ivan., an endemic medicinal species

Authors : Sandeep Kumar VERMA, Bahtiyar Buhara YÜCESAN, Songül GÜREL, Ekrem GÜREL

Pages : 743-750

View : 23 | Download : 10

Publication Date : 2011-12-01

Article Type : Research Paper

Abstract :This study describes, for the first time, an in vitro protocol for the development of somatic embryos and shoots from a callus derived from cotyledonary leaf segments excised from 3-week-old in vitro-germinated seedlings of Digitalis lamarckii Ivan. insert ignore into journalissuearticles values(dwarf foxglove);, an endemic medicinal species of Turkey. The embryogenic callus was induced on Murashige and Skoog insert ignore into journalissuearticles values(MS); medium containing 0.54 mM m-naphthalene acetic acid insert ignore into journalissuearticles values(NAA); and 2.22 mM 6-benzylaminopurine insert ignore into journalissuearticles values(BAP);. Somatic embryos developed readily when the embryogenic callus was transferred to MS medium containing BAP insert ignore into journalissuearticles values(4.44 or 8.87 mM); alone or BAP combined with NAA insert ignore into journalissuearticles values(1.34, 2.69, or 5.37 mM);. The most effective hormonal combination for somatic embryogenesis was 1.34 mM NAA and 8.87 mM BAP, which produced a mean of 37.0 embryos per cotyledonary leaf explant. An organogenic callus was induced on MS medium containing 2.69 mM NAA and 2.22 mM BAP. Shoot development was observed when the organogenic callus was transferred to MS medium containing different concentrations of BAP alone insert ignore into journalissuearticles values(2.22, 4.44, or 8.87 mM); or BAP combined with NAA insert ignore into journalissuearticles values(1.34 or 2.69 mM);. The highest mean number of shoots insert ignore into journalissuearticles values(5.67 shoots per explant); was obtained when the medium contained 8.87 mM BAP and 2.69 mM NAA. The regenerated shoots were readily rooted on MS medium containing 1.0, 2.5, or 5 mM indole-3-acetic acid insert ignore into journalissuearticles values(IAA); or indole-3-butyric acid insert ignore into journalissuearticles values(IBA);. Rooted regenerants were then transferred to the pots, where they grew well and attained maturity. Over 90% of the regenerants survived the hardening process. The protocol described could be useful for germplasm conservation, commercial cultivation, genetic improvement, and cardenolide production studies in D. lamarckii.
Keywords : Key words Digitalis lamarckii Ivan, dwarf foxglove, cotyledonary leaf segments, callus formation, somatic embryogenesis, shoot organogenesis