117 An In Vitro Regeneration System for Basil (Ocimum basilicum L.)
A plant regeneration protocol was successfully developed for basil (O. basilicum L.). Explants from 1-month-old seedlings yielded the highest frequency of regeneration of shoots (37%) with an average number of 3.6 shoots per explant. Calli and shoot induction were initiated on Murashige and Skoog (MS) basal medium supplemented with thidiazuron (TDZ) (4 mg/L) for ≈30 days. Shoot induction and development was achieved by refreshing the induction medium once after 14 days. The most morphogenetically responsive explants were basal leaf explants from the first fully expanded true leafs of greenhouse-grown basil seedlings. Developing shoots were then rooted on MS media in the dark without TDZ. Within 20 days, rooted plantlets were transferred and acclimatized under greenhouse conditions where they developed normal morphological characteristics. This is the first report of a successful in vitro regeneration system for basil through primary callus. The establishment of a reliable regeneration procedure is critical when developing a transformation protocol for enhancing the production of basil for insect and disease resistance and improved essential oil constituents.