Abstract

Shoot multiplication of chrysanthemum was achieved from shoot tip explant, using MS media supplemented with different concentrations and combinations of plant growth regulators. Different parameters including shoot initiation percentage, average number of shoots per explant, length of shoots (cm), number of leaves per shoot and number of nodes per shoot were studied during the course of study. Low concentration of indole-acetic acid (IAA, 0.1 mg/l) excelled all the other concentrations in almost all the parameters studied when used alone, as maximum shoot initiation (86.6%), shoot per explants (3.9), length of shoots (4.3 cm), number of leaves (10.0) and nodes (4.8) were recorded in it. Intermediate concentration of benzyladenine purine (BAP, 1.0 mg/l) is superior to all the other BAP concentrations used when used alone. MS media fortified with 1.0 mg/l BAP had produced the maximum shoot initiation (93.3%), shoot per explant (4.1), length of shoots (5.0 cm) number of leaves (11.0) and nodes (5.5). Similarly, when the combination of different concentrations of IAA and BAP were used, significant results regarding the regeneration of chrysanthemum plantlets were achieved. MS media supplemented with intermediate levels of BAP (1.0 and 2.0 mg/l) along with lower concentrations of IAA (0.1 and 0.2 mg/l) showed better results as compared to other concentrations and combinations. Satisfactory rooting response was obtained in half strength MS media supplemented with 0.2 mg/l indole butyric acid (IBA).

Key words: Chrysanthemum, Chrysanthemum morifolium, growth regulators, in vitro culture, shoot tip culture, indole acetic acid, benzyladenine purine, regeneration, rooting.