induced calli exceeding 1 mm were isolated and
individually transferred to dishes with solid MS
medium (Murashige and Skoog 1962) supplemented
with 4 % bacto-agar, 2 % sucrose, 0.2 mg/l indoleacetic
acid, and 4 mg/l zeatin. Dishes were incubated at
25 C under a 16/8 h photoperiod