Effect of abscisic acid on anthocyanin production in callus culture of Petunia hybrida cv. Bravo Blue

Development of an efficient tissue culture system for commercial production of anthocyanin requires an integrated approach combining the effects of various enhancement strategies. To develop a method which does not require the complicated operation and results in the anthocyanin induction in callus cultures of Petunia hybrida, we proposed a convenient culture method using Murashige and Skoog medium supplemented with different concentrations of Abscisic acid (ABA), viz., 0 (control), 20, 30, 40 and 50 μM and the callus cultured on it. Supplementation of 30 μM resulted in a synergistic increase in anthocyanin production in terms of pigment content and pigment production with highest response coefficient (91.29 ± 2.07%) in shortest duration (12.87 ± 0.18) days. Least response coefficient (65.55 ± 2.94%) was recorded under control treatment. The colour value index (CV) was observed maximum with the addition of ABA 30 μM (1.58 ± 0.08 CV g⁻¹ FCW) and maximum response for pigment production (3.22 ± 0.12^b CV test tube⁻¹). Significant reduction in the callus growth was observed due to addition of ABA as it was maximum in control treatment (3.15 ± 0.70 g). Anthocyanin pigmentation was observed as bluish-purple dots scattered over the callus.