Effects of polarity on bulblet regeneration on stem cuttings of Oriental Lilium Hybrid cv. Casa Blanca

Abstract

Oriental Lilium Hybrid cv. Casa Blanca is an important cut flower and garden plant. The study compared effects of in vitro bulblet induction on different oriented horizontally and vertically cultured cv. Casa Blanca stem explants with and without immersing them in agar solidified MS medium containing different concentrations of BAP. The results signified that orientation and immersing of explants into culture medium had significant effects on regeneration. Horizontally placed explants were advantageous over vertically placed upside up or upside down explants in terms of number of regenerated bulblets and their diameter. Maximum number of 6.84 ± 0.23 bulblets per "horizontally surface cultured stem explants" was noted on MS medium containing 0.20 mg/l BAP. These bulblets induced maximum mean bulblet diameter of 0.67 ± 0.02 cm Mean number of bulblets per explant was positively affected on horizontally cultured immersed explants. Contrarily, this parameters was negatively affected on vertically immersed upside up immersed and non immersed explants. However, vertically cultured upside down explants showed extreme inhibition with induction of bulblet initials only. The bulblets diameter was increased by culturing them on MS medium containing 4% sucrose for 8 weeks. Followed by their rooting on MS medium containing 0.5 mg/l IBA. They were acclimatized in greenhouse on peat moss prepared localy from leaves.