Factors Affecting Shoot Regeneration in Rough Lemon (Citrus Jambhiri Lush) Rootstock

The aim of this work was to standardize tissue culture parameters for gene transfer in rough lemon rootstock. Epicotyl segments were cultured with different concentrations of 6-benzylaminopurine (BAP), cefotaxime and hygromycin. Epicotyl segments (1–2 cm) from etiolated seedlings transferred to 16 h photoperiod for 2 weeks produced maximum number of adventitious shoot buds on MS medium supplemented with BAP (0.5 mgl⁻¹). Longitudinal cut gave the highest number of buds per explant as compared to transverse cut. Maximum bud induction frequency was obtained on MS + BAP (0.5 mgl⁻¹) medium. The sensitivity of epicotyl segments cultured on regeneration medium MS + BAP (0.5 mgl⁻¹) to antibiotics, cefotaxime and hygromycin was observed at concentration of 400 ppm and 2 mgl⁻¹, respectively. The study can help in developing transgenics of rough lemon rootstock.