AN IN-VITRO STUDY ON ORGANOGENESIS IN TREMA-ORIENTALIS (BLUME) LINN

Plant regeneration was achieved in leaf callus derived from 15-day-old in vitro grown seedling and mature tree of Trema orientalis naturally growing on chromite minewastes in a monsoon climate at Sukinda, India . Both types of explants formed callus which developed shoot buds in M S medium with benzyladenine (BA), I-naphthaleneacetic acid (NAA) and a denine sulphate (Ads). Transfer of the 4-week-old calluses to MS basal medium supplemented with 11.11 mu M (2.5 mg/l) BA and 1.34 mu M (0.25 mg/l) NAA resulted in the highest shoot regeneration rate (82.1%) in leaf derived calluses developed from seedling source; the rate of shoo t bud regeneration could be enhanced on incubation of the cultures und er the light intensity of 62.5 mu E/m(2)/s. The calluses obtained from leaves of mature trees were less efficient than those derived from se edling sources for shoot bud regeneration. Histological observations c onfirmed regeneration of shoot buds from leaf derived callus of T. ori entalis. Excised shoots were induced to form roots by transfer to 1/2 MS + 0.053 mu M (0.01 mg/l) NAA or 0.049 mu M (0.01 mg/l) indole-3-but yric acid (IBA). The rooted plantlets were established in soil.