Robust and reliable in vitro regeneration of Tossa Jute (Corchorus olitorius L. var. O-9897)

Lack of a rapid and robust in vitro regeneration protocol for Tossa jute (Corchorus olitorius L.) hinders the genetic transformation of jute crops for different agronomic traits of interest. The current study was conducted to develop a rapid, efficient, and reproducibleregeneration protocol for recalcitrant Tossa jute. The potential of auxins (IAA, IBA) and cytokinin (BAP) for the induction of callus, regeneration of shoot and formation of root from the cotyledon with attached petiole of cultivar O-9897 on MS was tested accordingly. Approximately, total 96 calli (out of 100 explants) were induced within 32 days on MS media harboring 2.5 mg/L BAP + 0.5 mg/L IAA. Within 5 weeks, about 95 calli regenerated total 99 shoots (86.6%) after 8–10 days of culture. Rooting of 52 regenerants (52.5%) was initiated on half-strength MS media supplemented with 1.0 mg/L IBA within 10 days. After acclimatization, a total of 52 rooted plantlets were transferred to the soil pot and 45 (86.53%) plantlets were survived and turned to normal plants without somaclonal variations. It is the first investigation analyzing foliar micro-morphological characters like stomata, trichomes, and vein patterning of leaves from in-vitro grown progeny and acclimatized plants that assess the developmental adaptation of micropropagated plantlets for survival under field conditions. The findings demonstrate morphological homogeneity between micropropagated plants regenerated from cotyledon explants with attached petioles and the mother plants. This is the pioneering report on foliar micromorphological analysis at subsequent micropropagation stages, confirming the phenotypic fidelity of regenerants.