In vitro shoot regeneration of hypocotyl explants of Foeniculum vulgare-a culinary and medicinal herb

Abstract

A reproducible protocol for in vitro shoot regeneration and plantlet establishment was developed from hypocotyl-derived callus explants of Foeniculum vulgare. Callus induction frequency was the highest (92%) on SH (Schenk & Hildebrandt) medium supplemented with 4.44 μM BA (N6-benzyladenine) and 1.34 μM NAA (α-naphthaleneacetic acid) followed by 86% and 80% on MS (Murashige & Skoog) and NN (Nitsch & Nitsch) medium respectively after 40 d of culture. The organogenic callus induced better shoot regeneration frequency (92%) on SH medium containing 6.66 µM BA as compared to 87% and 75% on MS and NN medium respectively. The highest number of 9.2 shoots per callus explant was achieved with the mean shoot length of 5.48 cm on SH medium supplemented with 6.66 µM BA followed by decreasing shoot production of 8.2 shoots and 7.3 shoots per callus explant on MS and NN medium respectively. The in vitro regenerated shoots produced the maximum root induction frequency of 94% on SH medium with 1.34 µM NAA, while on MS and NN media, frequencies of root induction were 86% and 77% respectively. There were 6.6 roots per shoot with an average root length of 6.4 cm on SH medium with a level of 1.34 µM NAA, while MS and NN media with the same level of auxin (1.34 µM NAA) induced an average of 5.8 and 5.3 roots per shoot respectively after 60 d of culture. In vitro derived plantlets acclimated successfully with 100% survival.