ROLE OF SALICYLIC ACID IN AMELIORATION OF SALT TOLERANCE IN POTATO (SOLANUM TUBEROSUM L.) UNDER IN VITRO CONDITIONS

Salicylic acid (SA) has long been considered as signal molecule and is known to reduce the oxidative damage caused by salinity stress. The objective of this said), was to work out a suitable methodology for improving salt tolerance in potato by the exogenous application of SA. For this purpose, In vitro plants of two economically important potato cultivars, i.e., Cardinal and Desiree were raised. Single nodal explants (1.0 cm long) from two-month-old in vitro potato plants were inoculated on MS medium with or without 60 mM NaCl supplemented with or without different concentrations (0.125, 0.25, 0.50 and 0.75 mM) of salicylic acid. Complete randomized experimental design was employed with 10 replicates and one nodal explant per treatment. After 60 days of inoculation, number of growth (root, shoot length, number of root, shoot and nodes, fresh/dry weight) and biochemical parameters (protein contents) were studied. Application of 60 mM NaCl to In vitro-grown potato plants in general adversely affected several growth as well as biochemical parameters. On the other hand, exogenously-applied SA enhanced the growth of both potato cultivars. It was observed that SA application at two higher tested levels (0.50 and 0.75 mM) did not confer much tolerance to NaCl stress in these potato cultivars in comparison with the lower concentrations (0.125, 0.25 mM) that proved quite effective in enhancing growth in Cardinal and Desiree, respectively. These results hint at a possibility that relatively low-to-moderate concentrations of salicylic acid may, in future, be useful in improving yield of potato plants under saline conditions.