This study was carried out, using callus derived from hypocotyl segment of Chinese cabbage (Brassica campestris ssp. pekinensis) by culture on media supplemented with various concentrations of NaCl and Na₂SO₄, to assess the change of metabolite contents, and water relations of callus tissues.
The percent of seed germination was much lower when cultured on the media containing NaCl (6.3% on 2% NaCl, 16 days after sowing), than Na₂SO₄ (95% on 2% Na₂SO₄, 9 days after sowing), and 80% of the seedlings died by 20 days after sowing.
α-Amino nitrogen content of callus subcultured once on NaCl-containing media was higher than that of control. In Na₂SO₄ treated plot, it increased in relation to increasing subculture times and salt concentrations. The protein content of callus cultured on salt containing media was higher than that of control, and was persistent regardless to subculture times. The contents of sucrose and reducing sugars increased in proportion to the number of subcultures and the concentration of salts. When compared to control, starch content was increased at 4th subculture in salt-containing media but decreased by increasing subculture times. Chlorophyll content of callus were higher with NaCl treatment than with Na₂SO₄ treatment, and increased in proportion to salt concentration except 1.0% NaCl treatment.
Both water and osmotic potentials of callus showed the most negative when cultured on 0.75% NaCl-containing media. In Na₂SO₄ treatment, water potential of callus tissues was slightly decreased in proportion to Na₂SO₄ concentration. Osmotic potential of callus tissues kept at around 20bars regardless of salt cocentration.
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