Growth and micronutrient acquisition of some apple varieties in response to gradual in vitro induced salinity

Abstract

Growth and micronutrient acquisition of some apple (Malus dometsica Borkh) varieties (Galla, MM 111, MM I06, M 26, and M6 York) were studied under gradually in vitro induced NaCl (from 0, 50 to 100 mM) salinity. Microshoot dry weight tended to increase with increasing salinity level in all varieties except in M 26 and M6 York as some decline was obtained at 100 mM NaCl. Shoot proliferation was decreased significantly in Galla at 100 mM NaCl and at both salinity levels in M 26 compared to the control (0 mM). A significant decrease in shoot zinc (Zn) acquisition with increasing salinity level was obtained in all varieties except MM 111. M6 York and MM 111 decreased their copper (Cu) acquisition significantly at 50 mM NaCl and then increased at 100 mM salinity level. Meanwhile, a significant decrease in Cu acquisition with increasing NaCl concentration was obtained in Galla and M 26. Galla, MM 106, and M 26 showed a significant increase in manganese (Mn) acquisition at 50 mM NaCl followed by a decrease at 100 mM salinity level. On the other hand, Mn acquisition continued to decrease significantly in MM 111 while M6 York increased its Mn acquisition with increasing salinity. M 111 and M6 York showed a significant decrease in iron (Fe) acquisition at 50 mMNaCl followed by an increase at 100mM NaCl. Galla and M 26 continued to decrease Fe acquisition with elevated salinity level, whereas Fe in MM 106 increased with salinity.