The Impact of Far-Red Light Supplementation on Hormonal Responses to Cold Acclimation in Barley

Cold acclimation, the necessary prerequisite for promotion of freezing tolerance, is affected by both low temperature and enhanced far-red/red light (FR/R) ratio. The impact FR supplementation to white light, created artificial LED sources, on hormone levels, metabolism, expression key metabolism-related genes was determined in winter barley at moderate (15 °C) (5 temperature. FR-enhanced tolerance 15 °C associated with abscisic acid (ABA) accompanied a increase indole-3-acetic (IAA) cis-zeatin levels. most prominent plants’ found after pre-treatment (for 10 days) followed cold treatment (7 days). response ABA diminished comparison treatment, probably due elevation stress during pre-treatment. Jasmonic (JA) salicylic (SA) were transiently reduced. When plants exposed directly combination supplementation, higher than JA and, longer term (after 7 days), IAA increase, which indicates stronger better acclimation. hardening more efficient when applied early developmental stage (three-leaf stage, 18 rather later stages (28-days). dynamics phytohormone changes are well supported profiles genes. This series treatments serves as evidence close relationship between plant hormones, quality, beginning Besides timing treatments, age also represents factor spectrum-dependent