The Growth of and Organ Formation from Callus Tissue of Sorghum

Successful culturing of callus has recently been reported for the following monocotyledonous species: corn (Reference 2, and Linsmaier Bednar, E. M., personal communication), oats (1, 6), rice root (8), asparagus (7), wheat (5), and sorghum (4). For the culture of sorghum callus from roots and tillering nodes, Strogonov et al., (4) used Murashige and Skoog's basal medium plus calcium pantothenate, 5 mg/liter; 2,4-dichlorophenoxyacetic acid, 1 mg/liter; kinetin, 1 mg/liter; casein hydrolysate, 0.5 g/liter; and ascorbic acid, 1 mg/liter. The same basal inorganic medium was also used for the culture of oats (1), asparagus (7), and by Linsmaier Bednar for corn. Corn callus was also cultured on White's medium (2), oats and rice root on Heller's medium (6, 8), and wheat on Hildebrandt's D medium (5). Generally, 2,4-D was used as the auxin, but a-naphthaleneacetic acid as well as 2,4-D was used for corn (2). In other respects the same nutrients and growth conditions were used as those required for the culture of dicotyledonous callus. The ability of monocotyledonous callus tissue to form organs has been demonstrated by the production of embryoids and plantlets from asparagus cells (7), many shoots but few roots from oats (1), roots from wheat callus (5), and roots (2) and both roots and shoots from corn callus (Linsmaier Bednar, E. M., personal communication). This report describes the culture of sorghum callus, the initiation of shoot primordia, and development of plants from callus tissue of this species.