SCREENING OF SOME DATE PALM CULTIVARS TO SALT STRESS IN VITRO
Salinity is a major problem in irrigated agriculture especially in the arid and semi-arid environments. Although date palm is considered as a high salt tolerant tree, limited information is available relating to the differences in salt tolerance among the cultivars. The aim of this study was to investigate the differences in resistance to NaCl stress among six date palm cultivars during germination stage. Isolated zygotic embryos were cultured on MS medium with different salt concentrations (0, 50, 150, 250, 350 mM) NaCl. The germination percentage and velocity, the length of radicle, the fresh weight and the dry matter content of the germinating embryos were determined. Results showed that the germination in all cultivars was not significantly affected by 50 mM NaCl. By increasing the NaCl concentration to 150 mM, the germination percentage was negatively affected for the cultivars Barhi, Zaghlool and Barban while Zahdi, Khistawi and Majhool showed higher tolerance. For higher concentration of NaCl (250 mM), the cultivars Zahdi and Majhool exhibited higher resistance than the other tested cultivars. The highest NaCl concentration (350 mM) was lethal for most of the cultivars, only Zahdi revealed some tolerance and the percentage of the germinating embryos reached to 28%. The velocity of germination decreased for all cultivars relating to the increase in the salt concentration more than 150 mM. The growth of radicle of most cultivars was also affected by salt treatment. Adding 50 mM NaCl to the medium stimulated the root growth. With 150 mM NaCl there was no difference in root growth compared to the control while it decreased significantly on medium enriched with 250 mM NaCl. Only Zahdi did not respond with differences in the length of radical on all tested NaCl concentrations.
Ibraheem, Y.M., Pinker, I., Böhme, M. and Al-Hussin, Z. (2012). SCREENING OF SOME DATE PALM CULTIVARS TO SALT STRESS IN VITRO . Acta Hortic. 961, 359-365
Phoenix dactylifera L., NaCl stress, germination percentage, germination velocity