Involvement of homocastasterone, salicylic and abscisic acids in the regulation of drought and freezing tolerance in doubled haploid lines of winter barley

摘要: Ten doubled haploid (DH) lines of winter barley with an increased range freezing/drought tolerance were used to identify phytohormones involved in plant stress acclimation. Cold hardening and drought applied at the most critical stages development on young seedlings heading plants, respectively. The level was significantly higher heading, more than 5-fold respect salicylic acid (SA) total brassinosteroids (BRs) 1.7-fold case abscisic (ABA). Moreover, spectrum detectable BRs from one—homocastasterone (HCS)—found four identified plants [HCS, castasterone (CS), teasterone dolicholide], last one detected for first time cereal species. To some extent freezing seems be determined by native hormonal status as control tolerant DH contained 1.4- 2.3-fold lower amount ABA HCS SA comparison freezing-sensitive ones. Such dependency not observed significant variation CS content only difference. Under treatments, accumulated (75–81%) ABA, which probably reflected intensity resulting another defence strategy. In contrast, stress-induced almost 2-fold increase HCS/CS 2–3-fold decrease specific suggest involvement these molecules defence. Detected correlations their interaction nonspecific peroxidase low molecular weight antioxidants.