Abstract

Nurul Aini1*, Emmanuel Mapfumo2, Zed Rengel2and Caixian Tang3

The combined effects of salinity and water logging on growth and ecophysiological characteristics of three Melaleucaspecies were investigated in a glasshouse study. Salinity treatments were imposed from day 28 at 0.3, 0.8, 2 and 5 g NaCl kg-1soil. Shoot Na+concentration and Na+/K+ratio for M. thyiodesat all salt level and of M. nesophilaat 5.0 g NaCl kg-1were higher under waterlogged as compared with non-waterlogged conditions. The concentration of Cl-was double in M. thyiodesand M. nesophilashoots after 2 weeks of water logging at 5 g NaCl kg-1soil, but not in M. halmaturorum. Final dry weights of shoots and roots of the three Melaleucaspecies decreased with increased salinity levels. Shoot dry weight of plants grown at 5.0 g NaCl kg-1soil decreased to 30, 50 and 11% of those achieved at 0.3 g NaCl kg-1soil for M. halmaturorum, M. thyoides, and M. nesophila, respectively. The results indicated different salinity resistance within Melaleucaspecies