Adventitious Bud Induction and Plant Regeneration in Epicotyl Segments of Bakrai (Citrus reticulata Blanco X C limetta Swing.)

摘要

Experiments were conducted to study the in vitro propagation of Bakrai using epicotyl explants. Explants were excised form in vitro grown seedlings, cultured on a basic MS medium supplemented with various concentrations of benzyladenine (BA) and naphthaleneacetic Acid (NAA). The highest percentage of explants producing normal adventitious shoots (83.3%) was obtained on a medium MS medium containing 2 mg L~(-1) BA. The maximum number of adventitious buds (20.33) produced in 4 mg L~(-1) BA, but most ofthese buds remained quiescent. Addition of 0.5 mg L~(-1) NAA increased shoot number and shoot length but higher NAA concentrations had an inhibitory effect on shoot regeneration, particularly in 1 mg L~(-1) BA concentration. The highest number of shoots(5.5) and longest shoots (9.68 mm) were obtained in concentrations of 2 and 1 mg L~(-1) BA plus 0.5 mg L~(-1) NAA, respectively. The shoots were rooted on a basal medium with half-strength MS salts and various concentrations of indolebutyric acid (IBA)(0.5-10 mg L~(-1) ). The highest percentage of rooting (91.67%) and the maximum number (1.71) and length (20.33 mm.) of roots were obtained with 10 mg L~(-1) IBA. The plantlets were transferred to pots containing an equal mixture (v/v) of sand and loamysoil and successfully acclimatized to natural environment with a survival rate of 80%.