Callus induction: The immature embryos were excised
aseptically from caryopses, and placed with the embryo axis
in a contact with a solid agar medium for callogenesis
containing the mineral salts of Murashige and Skoog (1962)
30 g L-1
sucrose and 2 mg L-1
2,4-D. The pH of this medium
was adjusted to 5.8 with 0.1 N NaOH and solidified with 7 g
L
-1
agar before autoclaving during 20 min at 120°C. Ten
explants per petri dish were cultivated and cultures were
kept in dark at 25±1°C