Spermine alleviates heat-induced senescence in creeping bentgrass by regulating water and oxidative balance, photosynthesis, and heat shock proteins

Spermine (SPM) is involved in response to abiotic stress plants, but the potential role of SPM regulating senescence has not been well documented. Objectives this study were examine effect changes endogenous polyamines (PAs) by application on improving heat tolerance creeping bentgrass (Agrostis stolonifera) and explore SPM-regulated associated with alterations water oxidative balance, photosynthesis, shock proteins under stress. The results showed that persistent high temperature caused severe damage significant decreases chlorophyll (Chl) content, photosynthetic efficiency, leaf content leading premature bentgrass, as reflected a upregulation transcriptions senescence-associated genes (AsSAG39, Ash36, Asl20). improvement spermidine (SPD) induced could significantly alleviate through maintaining higher Chl net rate, photochemical performance index absorption basis, promoting osmotic adjustment ability antioxidant enzyme (superoxid dismutase, catalase, peroxidase, ascorbate peroxidase) activities enhance scavenging capacity reactive oxygen species, upregulating protein (HSP) (HSP90-5, HSP90.1-b1, HSP82, HSP70, HSP26.7, HSP17.8, HSP12) helping maintain normal synthesis functions stress, thereby delaying heat-induced senescence. These findings reveal an important PAs perennial plants exposed environment.