Evaluation of In Vitro Regeneration Aptitude Through Histological Detection in Ocimum basilicum L

Sweet basil (Ocimum basilicum L.) is one of the most well-known aromatic herbs, which are economically important for food and pharmaceutical purposes. In vitro regeneration protocols are a fundamental part of molecular approaches, such as genome editing, which are used to enhance crop quality and pathogen resistance. In this research, in vitro regeneration methods were developed to examine the morphogenic aptitude of four different explant types from five commercial cvs of Ocimum basilicum L. (‘Prospera’, ‘Paoletto’, ‘Italiko FT’, ‘Dark opal’, and ‘Bolloso napoletano’). ‘Prospera’ showed the highest direct regeneration efficiency in all of the explant types (100% in the roots, 36% ± 0.02 in the cotyledons, 7.5% ± 0.2 in the hypocotyls, and 50% ± 0.04 in the cotyledonary nodes). The roots were found to be the most effective explant type, producing nodule-like meristems (100% in ‘Prospera’ and ‘FT Italiko’, 95.24% ± 0.01 in ‘Bolloso napoletano’), as precursors of shoots. Histological analysis was confirmed to be a suitable method to detect meristematic activity during the early morphogenic process and to evaluate the explants’ regeneration potential.