Enhanced nitrate reductase activity offers Arabidopsis ecotype Landsberg erecta better salt stress resistance than Col-0

The nitrogen utilization efficiency of plants varies depending on the plant species. In modern agriculture, nitrogen fertilizer is used to increase crop production, with the amount of fertilizer addition increasing steadily worldwide. This study included the two most used ecotypes of Arabidopsis thaliana, Landsberg erecta (Ler) and Col-0, which were used to identify differences at the molecular level. We found that the efficiency of nitrogen utilization and salt stress resistance differed between these two ecotypes of the same species. We demonstrated distinct salt stress resistance between Ler and Col-0 depending on the differences in nitrate level, which was explained by different regulation of the NIA2 gene expression in these two ecotypes. Our results demonstrate that the genes and promoters regulate expression of these genes and contribute to trait differences. Further studies are required on genes and promoter elements for an improved understanding of the salinity stress resistance mechanism in plants.