Comparative study on the effects of putrescine and spermidine pre-treatment on cadmium stress in wheat

Abstract

In several cases a correlation was found between polyamines and abiotic stress tolerance. However, the individual polyamines may have different effects, which also vary depending on the type of treatment. When applied as seed soaking or added hydroponically 0.5mM putrescine and spermidine, different changes were induced during 50µM cadmium stress in wheat plants. Seed-soaked plants were exposed to cadmium immediately after germination for 5 days, while plants pre-treated with polyamines hydroponically were stressed at age of 14 days for 7 days. Putrescine pre-treatment was beneficial both as seed soaking and applied hydroponically, while spermidine only had a protective effect in the case of seed soaking, enhancing the Cd-induced oxidative stress when were pre-treated hydroponically. The differences observed were related to the polyamine metabolism. The accumulation of endogenous putrescine beyond a certain amount may be in relation with the negative effect of hydroponic spermidine pre-treatment during Cd stress. The increased putrescine content was also correlated with the highest accumulation of Cd, salicylic acid and proline contents in plants treated with a combination of spermidine and Cd. However, the expression level of the gene encoding phytochelatin synthase was only influenced by hydroponically applied spermidine, which decreased it under cadmium stress. Changes in the activities of antioxidant enzymes, diamine and polyamine oxidases were also discussed.

Polyamine Function in Plants: Metabolism, Regulation on Development, and Roles in Abiotic Stress Responses

“…Under cadmium- and copper-induced oxidative stress, lipid peroxidation in sunflower leaf discs increased, while the activities of glutathione reductase (GR) and superoxide dismutase (SOD) decreased (Groppa et al, 2001). When plants were treated with exogenous PAs (1 mM), Spm treatment reduced the effects of Cd 2+ and Cu 2+ on lipid peroxidation almost to control values (Tajti et al, 2018). In addition, GR activity was completely restored by Spm or Spd treatments, and SOD activity under Cu 2+ treatment was restored by Spm treatment (Table 3).…”

The Role of Salicylic Acid in Plants Exposed to Heavy Metals

“…Many reports suggest that SA treatment influence PA content in plants [131,161]. Recently, Tajti et al [162] studied the role of putrescine and spermidine on wheat under Cd stress and also reported increased levels of SA in those plants; however, the exact mechanism involved in SA-mediated HM stress tolerance and the relationship between PA and SA in plants are still unknown.…”

Physiological impact of putrescine on Trigonella foenum-graecum L. growing under temperature stress

“…Treatment of Trigonella seeds with 5mM putrescine before exposing to temperature stress degrees removed the harmful effects induced by temperature stress on the measured yield parameters (Figure 1). Exogenous application of polyamines stimulates tolerance to high or low temperatures in various crop plants (Perez-Amador et al, 2002;Tajti et al, 2018). It was found that putrescine improves the yield and quality of bell pepper (Mahmood et al, 2017) and broccoli (Zheng et al, 2019).…”