ROOTING AND SHOOT GROWTH OF STEM CUTTINGS OF SALTCEDAR (TAMARIX CHINENSIS LOUR) UNDER SALT STRESS

A sand culture experiment was conducted to investigate the rooting of stem cuttings and growth of Tamarix chinensis irrigated with various dilutions of saline soil solutions extract (0 to 32 g L-1) containing about 31.5% Na+. Rooting of stem cuttings was higher at lower salinity, inhibited greatly when salinity was higher than 12 g L-1, but still 43% of stem cuttings rooted at 32 g L-1 salinity treatment. Sapling growth was stimulated at 4 to 8 g L-1 salinity level and inhibited significantly by higher than 12 g L-1 salinity treatment although growth continued at 32 g L-1 salinity. Na+ content in roots, stems and leaves increased with increase in salinity, while Ca2+ and K+ content in leaves and stems decreased. The contents of Ca2+ and K+ in roots remained unaffected by various treatments. With increase in salinity Mg2+ content increased in stems and leaves but decreased in roots. Proline contents of leaf, stem and root increased with increase in salinity which became more conspicuous at the salinity level of 12 g L-1 and above. Osmotic regulation was also formed an important mechanism for Tamarix chinensis while growing under salinity.