Authors : Basim S. Yousif, Li Yun Liu, Nguyen T. Nguyen, Yosikuni Masaoka and Hirofumi Saneoka
Abstract: New Zealand spinach (Tetragonia tetragonioides) is widely cultivated throughout the world for use as a vegetable, ground cover and medicinal plant. In this study, New Zealand spinach and Chard (Beta vulgaris) were subjected to 0, 50, 100 and 200 mM NaCl for 14 days and tested for differences in salt tolerance. The growth of Chard was markedly inhibited by NaCl treatment, whereas, in New Zealand spinach, plant growth was increased at a low NaCl concentration (50 mM) and slightly decreased with increasing salinity. The leaf water potential and osmotic adjustment in New Zealand spinach was higher than that in Chard under salt stress. The proline content of New Zealand spinach rose with increasing salinity and the accumulation of proline was higher than in Chard on most of the salt stress treatments. Salt stress induced Na accumulation in the leaves of both species but the accumulation was lower in New Zealand spinach than in Chard. The potassium content of both species decreased with increasing salinity but the K content of New Zealand spinach was higher than in Chard. The lipid peroxidation (as measured Malondialdehyde MDA) content of Chard was significantly higher than that in New Zealand spinach at a higher salinity. The photosynthetic rate was decreased by salt stress, but that in New Zealand spinach was maintained at a higher level compared with Chard. These results indicated that New Zealand spinach is more salt tolerant than Chard.
Basim S. Yousif, Li Yun Liu, Nguyen T. Nguyen, Yosikuni Masaoka and Hirofumi Saneoka, 2010. Comparative Studies in Salinity Tolerance Between New Zealand Spinach (Tetragonia tetragonioides) and Chard (Beta vulgaris) to Salt Stress. Agricultural Journal, 5: 19-24.