Exogenous EBR Ameliorates Endogenous Hormone Contents in Tomato Species under Low-Temperature Stress

Low-temperature stress is a type of abiotic that limits plant growth and production in both subtropical tropical climate conditions. In the current study, effects 24-epi-brassinolide (EBR) as analogs brassinosteroids (BRs) were investigated, terms hormone content, antioxidant enzyme activity, transcription several cold-responsive genes, under low-temperature (9 °C) two different tomato species (cold-sensitive cold-tolerant species). Results indicated treatment with exogenous EBR increases content gibberellic acid (GA3) indole-3-acetic (IAA), whose accumulation reduced by low temperatures cold-sensitive species. Furthermore, combination or contribution BR abscisic (ABA) synergetic interaction was recognized between ABA response to temperatures. The malondialdehyde (MDA) proline significantly increased species, stress; however, did not affect MDA content. Moreover, present effect application stress, which catalase (CAT) activity glutathione peroxidase (GPX) expression levels genes influenced treatment. Overall, our findings revealed temperature causes oxidative while may decrease reactive oxygen (ROS) damage into increasing enzymes, improve rate affecting auxin gibberellin This study provides insight mechanism BRs regulate stress-dependent processes tomatoes, theoretical basis for promoting cold resistance tomato.