Transcriptional analysis of salt-responsive genes to salinity stress in three salt-tolerant and salt-sensitive Barely cultivars

Abstract

Salinity is a crucial limiting factor behind crop production in the world. Understanding the mechanisms of salinity-stress response could contribute to the improvement of salt tolerance in plants. We assessed the effect of salinity treatment (0, 100 and 200 mM), 24 h, 3 days, and 3 weeks after salt exposure on morphological characters and gene expression pattern of two barley cultivars; Sahara and Clipper and a new Advanced line. The expression pattern of 8 salt-inducible genes namely βFRUCT3, L1s1, HSP17.8, AOS, SBP, PEAMT, Na+-transporter, and ATLS1) was investigated in barley shoots using the real-time RT-PCR. Plant height, number of leaf/plant, number of tiller/plant, shoot fresh and dry weight and shoot water content were measured. The NaCl treatment significantly affects shoot fresh and dry weight as well as shoot water content and significant differences were observed among genotypes for all the studied traits except shoot dry weight and number of leaf/plant. The expression of the studied genes except ATLS1 was significantly affected by salt treatment, genotype and timepoint exposure to salinity. The mRNA level of βFRUCT3, L1s1, PEAMT and Na+-transporter genes was up-regulated in the salt-tolerant cultivar Sahara and down-regulated in the salt-sensitive cultivar Clipper after 3 weeks exposure to salt treatment.