PLANT-REGENERATION FROM PROTOPLAST-DERIVED CALLUS OF SUGARCANE

In 5 sugarcane clones, cell suspension cultures were initiated and mai ntained in modified N6 liquid medium containing 2 mg/l 2, 4-D, 500 mg/ l casein hydrolysate and 3 % sucrose, These suspension cultures were a ble to regenerate plants for more than three months, Protoplasts isola ted from these suspensions were embedded in 1.2 % agarose (modified KM 8P medium) and cultured in modified KM8P medium with the addition of n urse culture cells from the suspension culture, After several weeks of culture, calluses were obtained in all the 5 clones, Calluses derived from protoplasts were cultured for 2 weeks on PR4 medium (pre-culture medium for regeneration), then transferred to R9 regeneration medium, In the subsequent 30-day period of culture, protoplast-derived callus es of US 76-9 and NiF 8 regenerated green shoots and albino shoots, re spectively, while the other 3 clones did not form any organs, In the 6 experiments using suspension cultures of US 76-9 differing in age (8 to 31 weeks after initiation), regeneration of fertile green shoots fr om protoplast-derived calluses was observed, After the transfer to R1 medium for rooting, a few shoots developed to plants, while most of th e shoots died without rooting.