In Vitro Regeneration Of Plants From Sugarcane Seed-Derived Callus

Sugarcane (Saccharum spp. hybrid cv. CP 84-1198) seeds were germinated on modified Murashige and Skoog (MS) basal medium alone or supplemented with 2.3, 4.5, 11.3, 22.5, and 45.0 mu M thidiazuron (TDZ), or 4.5, 13.6, 22.6, and 45.0 mu M 2,4-dichlorophenoxyacetic acid (2,4-D), or 4.1, 12.4, 20.7, and 41.3 mu M picloram. Both auxins delayed seed germination by approximately 5 d. Maximum germination was observed on MS medium supplemented with 45.0 mu M TDZ. Callus induction occurred for seed germinated on 2,4-D and picloram-containing media, but not on TDZ medium. The greatest amount of callus (554 plus or minus 198 mg per seed) was produced on 4.1 mu M picloram. For shoot initiation, calluses were transferred to MS medium alone or supplemented with 2.5 mu M TDZ. The highest number of shoots was recorded on TDZ medium from callus that had been obtained originally from media containing either 4.1 or 12.4 mu M picloram or 13.6 mu M 2,4-D ( similar to 500). All shoots developed roots and grew to maturity on medium with 24.6 mu M indolebutyric acid.