Abstract
This study compared the concentrations of components such as nitrate, organic acids, free amino acids, cations and sugars in komatsuna (Brassica campestris var. perviridis) grown with carbonate, sulfate and chloride application (CO3-TK, SO4-TK and Cl-TK, respectively). The komatsuna was cultivated in 1/2000-a Wagner pots (6 hills per pot) filled with light-colored Andosol in a glasshouse for 37 days at soil water potential (SWP) right before harvesting of −6.2 and −62 kPa. And 26.5 mmolc of carbonate, sulfate or chloride in the form of potassium salts was applied to each pot. Chloride application to the komatsuna induced relatively high concentrations of potassium, calcium and magnesium ions, and the low concentrations of malate, glucose and fructose on a dry weight basis (DWB). Carbonate application induced relatively high concentrations of malate and low concentrations of nitrate. Sulfate was almost between chloride and carbonate. Concentration variation was not substantial in free amino acids. Those tendencies were almost the same in both SWPs. Most of the variations in component concentrations were attributed to the regulation of ionic and osmotic balance to respond to chloride, nitrate and sulfate absorption, as judged from quantitative relationships among the components and water in the komatsuna. It seems that the absorption of nitrate is influenced by the pH of the soil. There were clear differences in glucose, fructose and malate concentrations among CO3-TK, SO4-TK and Cl-TK on a fresh weight basis just as on a DWB.
