Betaine accumulation and the change of betaine-aldehyde dehydrogenase activity in barley seedlings under KCl and NaCl stress

The changes in growth status, ion contents, betaine levels and betaine\|aldehyde dehydrogenase (BADH) activity in seedlings of nonhalophyte barley treated with different concentrations of NaCl and KCl were studied. Results showed that the inhibition of growth in barley seedlings increased as enhancing NaCl and KCl for 96h and NaCl inhibitory degree was higher than that of KCl. The K\++ content of barley seedlings in NaCl was lower than the control, while the Na\++ content was higher, the levels of Na\++ fell in the seedlings treated with KCl, but K\++ levels rose, and K\++ content was higher than that of Na\++. The betaine levels of barley shoots rose with the increase in both external salt concentration and treatment time. Higher BADH activity was observed in low\|salt concentration but lower slightly in high\|salt concentration.