In Vitro selection and biochemical characterization of carnation (Diathus caryophyllus L.) callus culture tolerant to Alternaria dianthi

For the establishment of callus cultures of carnation (Dianthus caryophyllus L.), internodal segments were used as explants. Maximum percentage of callus induction was obtained on Murashige and Skoog (MS) medium supplemented with 2.0 mg/l naphthalene acetic acid (NAA) and 2.0 mg/l kinetin. Whereas, maximum shoot regeneration was obtained on medium supplemented with 2.0 mg/l 6-benzyladenine (BA) and 0.5 mg/l NAA. Well developed root system was obtained on liquid MS medium supplemented with 2.0 mg/l indole–3-butyric acid (IBA) and 0.2 per cent activated charcoal. Calli were subjected to different concentrations of culture filtrate of Alternaria dianthi and cell survival at 15 per cent selective dose of culture filtrate was 11.67 per cent. Selected calli showed significantly higher levels of biochemical constituents viz., total sugars, phenols, reducing sugars and proteins as compared to non-selected calli. Banding patterns of isozymes esterase, peroxidase and polyphenol oxidase were different in selected and non selected calli. In vitro shoot regeneration from selected calli was obtained on MS medium supplemented with 2.0 mg/l thidiazuron (TDZ).