PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

Regeneration potentials of Gerbera jamesonii bolus through tissue culture were studied using leaf, flower stalk and flower bud explants. In the present study, the explants (flower bud, flower stalk and leaf segment) of two gerbera varieties viz. yellow and pink were collected from field grown plants. These explants were inoculated into MS media supplemented with various types of growth regulators for the callus induction and subsequent in vitro regeneration of plantlets. The nature and texture of callus, response to shoot initiation and multiplication and induction of roots were different on the basis of varieties, types of explant and hormonal combinations. The best callus induction was obtained in MS medium supplemented with 4.0 mg/l BAP+1.0 mg/l NAA from all three explants of two varieties. Callus derived from leaf segment was brownish friable and nonregenerative but callus from flower bud and flower stalk were whitish nodular and regenerative in nature. MS medium with 3.0 mg/l BAP+0.5 mg/l NAA was optimum for shoot regeneration and 2.0 mg/l BAP for shoot multiplication of all two varieties. Highest root induction was recorded in MS medium with 0.3 mg/l IBA+0.1 mg/l GA₃ for both varieties. After sufficient root formation, in vitro regenerated plantlets were acclimatized gradually and best survival rate after acclimatization was 80%. Between two varieties, pink was more responsive genotypes in terms of ability to primary culture establishment, rate of callus induction, shoot initiation and multiplication, root formation and acclimatization.