Ion accumulation in different organs of green bean genotypes grown under salt stress

Salt-tolerant Gevas Sink 57 (GS57) genotypes and salt-sensitive 4F-89 French variety, previously determined in our preliminary study, were used in the study. The genotype and the variety exposed to 100mM NaCl application developed different mechanisms to be protected against toxic effects of Na+ ion. Salt-sensitive 4F-89 French variety let Na+ accumulate in all organs. On the contrary, salt-tolerant GS57 did not avoid salt and acted selectively among ions; the majority of toxic ion Na+ accumulated in old leaves and shoots and the plants did not transport them into young leaves. K+ accumulation was high in organs in which Na+ concentrations were low, and vice versa; Na+ content was low in young and high in old leaves of GS57, but K+ content was opposite. Ca2+ content in young leaves of GS57 and 4F-89 decreased; still its content was the highest of all examined ions found in young leaves. This indicated that beans can develop different mechanisms to accept and adapt high levels of salt. Storing toxic ion (Na+) in old leaves and having a limited transmission of salt into young leaves serves as a protection from detrimental effects of salt.