Callus induction and embryogenesis of alfalfa (Medicago sativa L.) using hypocotyl thin cell layer culture

This research is performed for evaluating the morphogenesis responses of thin cell layers (TCL) of alfalfa (Medicago sativa cv. Karysary) hypocotyls. TCLs (0.1–0.5 mm) were obtained from sterile hypocotyls that were cultured to SH medium containing various combinations of 2,4-D and kin (0, 0.5, 1, 1.5 and 2 mg/l). Unexpectedly, the percentage of callus induction (PCI) and Callus diameter (CD) were not affected by different concentrations of 2,4-D and kin. PCI was 100% without any correlation to hormonal combinations. Significantly the difference between concentrations of 2,4-D and kin for percentage of somatic embryogenesis (PSE) was observed (p < 0.01) so that, the maximum PSE occurred with 1.5 mg/l 2,4-D and without kin. The 2,4-D and kin interaction was not significant for PSE showing that each of these hormones affected by PSE independently. The number of embryoids (NE) was significantly different on the various concentrations of 2,4-D (p < 0.05) and maximum NEs were observed on 1.5 mg/l 2,4-D and without kin.