PLANT-REGENERATION FROM MESOPHYLL PROTOPLASTS OF LISIANTHUS (EUSTOMA-GRANDIFLORUM) BY ADDING ACTIVATED-CHARCOAL INTO PROTOPLAST CULTURE-MEDIUM

Plant regeneration from isolated protoplasts of 8 cultivars of lisiant hus, Eustoma grandiflorum (Griseb.) Schinners, has been established by using activated charcoal. Protoplasts were isolated from lisianthus l eaves grown in vitro and started to divide within 3-4 days of culture, but successful colony formation was only achieved by adding gellan gu m blocks containing 1% (w/v) activated charcoal immediately after cult ure. Colonies consisting of as many as 50-100 cells formed after 30 da ys of culture and were transferred to fresh medium for callus prolifer ation and shoot regeneration, respectively. These shoots rooted on MS medium containing 0.5 mg l(-1) indolebutyric acid(IBA) and the plantle ts were finally transplanted to pots. Morphological characteristics, g rowth habit and pollen fertility of protoplast-derived plants of one c ultivar were not different from those of seed-grown plants as control.