In vitro regeneration and adventitious root culture of Brassica oleracea var. acephala

Abstract

The in vitro regeneration, adventitious root culture and antioxidant activity of different regenerated tissues of Brassica oleracea var. acephala were investigated. Indirect shooting was induced from leaf explant of in vitro seed derived plants on MS medium containing different plant growth regulators. The optimum callus formation was observed on MS medium containing Naphthalene Acetic Acid (NAA, 1.0 mg/l) and 6-Benzyladenine (BA or BAP, 1.5 mg/l) or Thidiazuron (TDZ, 2.5 mg/l) + NAA (1.0). After subculturing the callogenic explant on MS medium containing TDZ (2.0 mg/l) + NAA (0.5 mg/l), 85 % shooting was achieved. Further subculturing on MS medium containing TDZ (2.5 mg/l) + NAA (1.0 mg/l) resulted into shoots with maximum number (12) and optimum length (5.4 cm) per explant. Rooting of elongated shoots was achieved on MS medium containing NAA (1.0 mg/l). Adventitous roots were induced from leaf explant of B. oleracea var. acephala on MS medium supplemented with auxins; NAA, IAA and IBA with concentration of 0.1, 0.5, 1, 1.5 mg/l for each plant growth regulator. Best adventitious rooting was achieved at MS medium containing 1 mg/l NAA with maximum 87 % rooting, 35 roots per explant, 2.986 g Fresh Weight (FW) and0.238 Dry Weight (DW). Effect of sucrose concentration and pH was also studied for adventious rooting at MS medium containing 1 mg/l NAA. MS medium with 3 % sugar strength was recorded as the best medium on which maximum 93 % adventious rooting with 2.23 g FW and 0.1 g DW were recorded. 5.8 were recorded as the optimum pH for induction of adventitious rooting on which 85.5 % rooting; 2.33 g FW and 0.186 g DW were recorded. These roots were sub-cultured in shake flask and increase in biomass was determined after each week, tell maximum biomass per 30 ml media was achieved. The antioxidant activity of regenerated tissues was determined and optimum scavenging activity was found in seed derived plants (36.58 %) followed by regenerated (27.5 %) and lowest activity (7.8 %) was in AR directly excised from leaf after induction followed callus (23.4 %). Key Words: Brassica oleracea var. acephala; organogenesis, Adventitious root culture, Thidiazuron, 6-Benzyladenine, Naphthalene Acetic Acid, Fresh Weight, Dry Weight, Antioxidant activity.