Melatonin Pretreatment Confers Heat Tolerance and Repression of Heat-Induced Senescence in Tomato Through the Modulation of ABA- and GA-Mediated Pathways

• DOI: 10.3389/fpls.2021.650955
• Publication Date: 2021-03-25T07:48:04Z
• Authors: Mohammad Shah Jahan; Sheng Shu; Yu Wang; Md. Mahadi Hasan; Ahmed Abou El-Yazied; Nadiyah M. Alabda...; Dina Hajjar; Muhammad Ahsan Altaf; Jin Sun; Shirong Guo
• Keywords: Senescence; Paclobutrazol

Heat stress and abscisic acid (ABA) induce leaf senescence, whereas melatonin (MT) gibberellins (GA) play critical roles in inhibiting senescence. Recent research findings confirm that plant tolerance to diverse stresses is closely associated with foliage lifespan. However, the molecular mechanism underlying signaling interaction of MT GA ABA regarding heat-induced senescence largely remains undetermined. Herein, we investigated putative functions suppressing tomato how coordinate each other presence MT. Tomato seedlings were pretreated 100 μM or water exposed high temperature (38/28°C) for 5 days (d). significantly accelerated damage photosystem upregulation reactive oxygen species (ROS), generating RBOH gene expression. Melatonin treatment markedly attenuated as reflected by reduced yellowing, an increased Fv/Fm ratio, ROS production. The Rbohs gene, chlorophyll catabolic genes, senescence-associated expression levels suppressed addition. Exogenous application elevated endogenous contents but content high-temperature-exposed plants. inhibited paclobutrazol (PCB, a biosynthesis inhibitor) sodium tungstate (ST, treatment. MT-induced heat was compromised both inhibitor-treated transcript abundance genes repressed; however, upregulated MT-treated Moreover, suppressor inhibited, while application. Taken together, MT-mediated suppression has collaborated activation inhibition pathways tomato.