In vitro salt stress tolerance of 'Sahand' cultvar grafed on two wild almond rootstocks: An evaluaton of physiological and biochemical traits between rootstocks

The low salinity tolerance of almond cultvars can cause a significant setback in almond producton. Therefore, selectng suitable cultvars and root-stocks in salinity-affected areas can facilitate sustainable crop producton. In this research, the effects of two wild almond species, Badamkohiand Arjan as rootstocks on the salinity tolerance of 'Sahand' as a scion were investgated through in vitro culture. A factorial experiment of 2 (species) x 4 (levels of salinity) was conducted in a completely randomized design (CRD) with 4 replicatons. The results showed that 'Sahand' grafed on Badamkohi had the higher fresh and dry weight than grafed on Arjan in all level of salinity. The [Na.sup.+] and [Cl.sup.-] ions contents inthe shoots and root of both micrografing combinatons increased with increasing salinity. However, their amount in the shoot and the root of 'Sahand'/Arjan plants were significantly higher than those ions in 'Sahand'/Badamkohi plants at 80 and 120 mM NaCl. The amount of total chlorophyll in 'Sahand' grafed on Badamkohi was 0.68 mg [g.sup.-1] FW which was significantly higher than the total chlorophyll of the same scion grafed on Arjan rootstock (0.51 mg [g.sup.-1] FW) at 120 mM NaCl. The highest leaf cell electrical leakage occurred in 'Sahand' grafed on Arjan which was significantly higher than leaf electrical leakage of the same scion grafed on Badamkohi at 120 mM NaCl. The grafing combinaton of 'Sahand'/Badamkohi showed a higher proline and glycine betaine content, compared to the grafing combinaton of 'Sahand'/Arjan. The shoot and root antoxidant enzyme actvites (SOD, POX and CAT) in micrografing combinaton of 'Sahand'/ Badamkohi were also significantly higher than those in 'Sahand'/Arjan. It can be concluded that 'Sahand/Badamkohi combinaton is a suitable choice for the regions with late spring frost and saline conditons.