The effect of salicylic acid on germination and seedling growth of Balangu (Lallemantia royleneana) under salinity stress

In order to investigate the effect of different levels of salicylic acid and salinity stress on germination characteristics and seedling growth of the medicinal plant of Balangu (Lallemantia royleneana), a factorial experiment was conducted based on completely randomized design (CRD) with three replications. Experimental factors included four different concentrations of salicylic acid (۰.۰, ۱.۰, ۲.۰ and ۳.۰ mM) and two different salinity levels (۰.۰ and ۱۰۰.۰ mM). Based on the result, interaction of salinity stress and salicylic acid for all the traits was significant. With the increase in salinity levels, including a reduction occurred for the traits of root length, shoot length, germination percentage, germination rate, vigor index, root length/shoot length ratio, and relative water content (RWC). For RWC, control with the maximum value of ۱۲.۱۳% and combination of (SA ۰, and NaCl, ۱۰۰ Mm) was minimum value (۱.۷۵). The highest germination percentage (۹۵.۵۵%) was for the combination of (SA, ۳ Mm and NaCl, ۰.۰). The highest vigor index (۵.۷۳) was for (SA, ۲ Mm and NaCl, ۰.۰ mM) and the lowest was observed for (SA, ۰.۰ mM and NaCl, ۱۰۰ mM). The highest correlation coefficient (۰.۹۳۶) was observed between the germination percentage and germination rate. Finally, application of ۳ mM salicylic acid was introduced as the best treatment in salinity stress conditions.