Low red to far-red (R/FR) ratio enhances freezing tolerance at 15°C in winter wheat and in winter barley genotypes (B-C) but not in winter einkorn wheat (A). Under the low R/FR ratio, the expression level of CBF14 gene is much higher in winter wheat and in winter barley (E-F) than in winter einkorn wheat (D). The expression of Phytochrome A (PHYA) increases in each genotype under low R/FR ratio (G-I), but the PHYB level increases only in winter einkorn wheat significantly (G-I).