Role of plant growth regulators on shoot formation from bulb sacles of Lily Sorbonne

Abstract

In this study, plant growth regulators included 2,4-dichlorophenoxyacetic acid (2,4-D), picloram, 6-benzylaminopurine (BA) and thidiazuron (TDZ), at different concentrations were used individually or in combination to induce adventitious shoots from bulb scales of Lily Sorbonne. Morphological and physiological changes in shoot formation from bulb scales were analysed. The maximum number of shoots per explant were obtained on Murashige and Skoog medium (MS) supplemented with 2,4-D 1 mg/L, BA 1,5 mg/L, zeatin 0,2 mg/L and indole-3-acetic acid (IAA) 0,5 mg/L. The adventitious shoots were derived from parenchymal cells, which placed under epidermis cells. This process included the following stages: activation of cell division with large nucleus, thin-walled and without starch granules; initiating of meristematic region; formation of shoot primordium and shoot with leaves. Use of 1-naphthylphthalamic acid (1-NOA) and N-1-naphthoxyacetic acid (NPA), auxin transport inhibitors, showed the role of polar auxin transport in shoot formation. The correlation of plant hormone, respiration rate and shoot formation from bulb scales was discussed.