Enhanced In Vitro Shoot Regeneration in Oldenlandia umbellata L. by Using Quercetin: A Naturally Occurring Auxin-Transport Inhibitor

Abstract

An efficient in vitro propagation method for a dye yielding medicinal herb, Oldenlandia umbellata L. was established using benzyl adenine and quercetin. Nodal segments cultured on agar gelled Murashige and Skoog medium supplemented with benzyl adenine (5.0 μM) and quercetin (5 μM), produced maximum explant response (100 %) and number of shoots (118.67). Thus a continuous shoot multiplication system in every 4 weeks interval was established. Addition of quercetin in combination with benzyl adenine produced significantly (p < 0.001) higher number of shoots than medium supplemented benzyl adenine alone and in short, addition of quercetin resulted in 1.5 fold increase in shoot number. Addition of 5 µM quercetin in combination with 5 µM benzyl adenine resulted in the production of 4.64 cm sized shoots with an average of 4.13 nodes per shoot. In vitro raised microshoots were rooted ex vitro, by a pulse treatment in 50 µM indole-3-butyric acid for 30 s, followed by planting in plastic cups containing potting mixture. Ex vitro planted microshoots were rooted and recorded high rate of survival (81.3 %). The present protocol in brief, suggests that by modifying auxin transport in a tissue culture system, rate of shoot multiplication can be increased, thus facilitating mass propagation of plants having strong apical dominance.