Versatile roles of polyamines in improving abiotic stress tolerance of plants

Abstract

In recent years, extreme environmental cues such as abiotic stresses, including frequent droughts with irregular precipitation, salinity, metal contamination, and temperature fluctuations, have been escalating the damage to plants’ optimal productivity worldwide. Therefore, yield maintenance under extreme events needs improvement in multiple mechanisms that can minimize the influence of abiotic stresses. Polyamines (PAs) are pivotally necessary for a defensive purpose under adverse abiotic conditions, but their molecular interplay in this remains speculative. The PAs’ accretion is one of the most notable metabolic responses of plants under stress challenges. Recent studies reported the beneficial roles of PAs in plant development, including metabolic and physiological processes, unveiling their potential for inducing tolerance against adverse conditions. This review presents an overview of research about the most illustrious and remarkable achievements in strengthening plant tolerance to drought, salt, and temperature stresses by the exogenous application of PAs. The knowledge of underlying processes associated with stress tolerance and PA signaling pathways was also summarized, focusing on up-to-date evidence regarding the metabolic and physiological role of PAs with exogenous applications that protect plants under unfavorable climatic conditions. Conclusively, the literature proposes that PAs impart an imperative role in abiotic stress tolerance in plants. This implies potentially important feedback on PAs and plants’ stress tolerance under unfavorable cues.

The synergy of halotolerant PGPB and mauran mitigates salt stress in tomato (Solanum lycopersicum) via osmoprotectants accumulation

“…Other interesting metabolites in plant responses to salt stress are polyamines. Polyamines are organic polycations involved in many processes of plant growth and development, including antioxidant systems and ionic homeostasis or photosynthetic pigment defense (Shao et al, 2022). Polyamine biosynthetic pathway included the first polyamine synthesized via arginine descarboxylase or ornithine descarboxylase called putrescine.…”

“…Similar results were previously described in the application of copper nanoparticles that induce salt tolerance of tomato by stimulating the antioxidant mechanism such as phenols(Pérez-Labrada et al, 2019).Other interesting metabolites in plant responses to salt stress are polyamines. Polyamines are organic polycations involved in many processes of plant growth and development, including antioxidant systems and ionic homeostasis or photosynthetic pigment defense(Shao et al, 2022). Polyamine biosynthetic pathway included the first polyamine synthesized via arginine descarboxylase or ornithine descarboxylase called putrescine.…”

The polyamines spermine and spermidine inhibit or induce programmed cell death inArabidopsis thaliana in vitroandin vivoin a dose dependent manner

“…For example, PA accumulation was observed prior to PCD induction by cadmium treatment in both Malus hupehensis seedlings (Jiang et al, 2012) and tobacco BY-2 cells (Kuthanová et al, 2004), as well as during HR PCD in Nicotiana tabacum (Torrigiani et al, 1997; Yoda et al, 2006), rice and Arabidopsis (Yoda et al, 2009). However, the literature reports on effect of PAs on PCD are often conflicting, with many studies reporting pro-survival effect of exogenous PAs supplementation under conditions such as aluminium stress (Yu et al, 2018) and salinity stress (Duan et al, 2008), and increases in PAs levels are generally associated with both abiotic and biotic stress resistance (Hussain et al, 2011; Shao et al, 2022). To ascertain if exogenous PAs can indeed modulate PCD response in a concentration dependent manner, we tested the effect of pre-treatment with sublethal levels of SPD and SPM on cell death induced by SA, a phytohormone implicated in PCD induced by biotic stress (Alvarez, 2000; Raffaele et al, 2006; Radojičić et al, 2018).…”

Effect of spermidine on reproductive, seed quality and bio-physiological characteristics of chickpea (Cicer arietinum L.) genotypes under salt stress

“…Recognized for its nutritional value, chickpea is a good source of protein, vitamin B, and Potassium. In chickpea cultivation, Rhizobium bacteria are inoculated to enhance root nodulation, fixing 70% of soil nitrogen biologically and improving soil fertility (Shao et al 2022). Chickpea is particularly sensitive to Cl dominated salinity.…”

“…Among them, Spd is notably involved in plant stress response signalling and the initiation of tolerance mechanisms. Foliar application of Spd increases endogenous polyamine levels with Spm + Spd/Put ratio rising further under stress conditions (Shao et al 2022). Exogenous Spd application enhances non-enzymatic antioxidant phenols, stabilizing membranes chaperones, binding to negatively charged surfaces and safeguarding membranes and biomolecules (Chen et al 2018).…”