Efficient in vitroChrysanthemum morifolium L.) plantlets from nodal segments

Abstract

Efficient plant regeneration system has been developed from the nodal segments of chrysanthemum (Chrysanthemum morifolium L). Nodal segments, after being sterilized with 1.0% mercuric chloride for three minutes, were inoculated in Murashige and Skoog (MS) media with varied concentrations of indole acetic acid (IAA), benzylaminopurine (BAP) and their combinations. 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. Intermediate level (0.3 mg/l) of IAA exceeded all the other concentrations of IAA by producing 80.0 % shoot initiation, an average of 4.0 shoots per explants, 5.1 cm long shoots, 11.3 leaves and 5.6 nodes per shoot, when used alone. Similarly, intermediate level of BAP (1.0 mg/l) showed its supremacy over all the other concentrations as it produced 100% shoot initiation, 4.9 shoots per explant, 5.8 cm long shoots, 13.4 leaves and 6.3 nodes per shoot, when used alone. When the combination of different concentrations of IAA and BAP were used, significant results regarding the regeneration of chrysanthemum plantlets were also achieved. MS media supplemented with lower concentrations of IAA (0.1 and 0.2 mg/l) along with intermediate levels of BAP (1.0 and 2.0 mg/l) had a favorable effect on the regeneration of chrysanthemum plantlets using nodal segments of chrysanthemum, 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), followed by 0.2 mg/l naphthalene acetic acid (NAA) and IAA, respectively.

Key words: Chrysanthemum, Dendranthema morifolium, growth regulators, in vitro culture, nodal segments, auxins, rooting.