Supplementation of nitric oxide and spermidine alleviates the nickel stress-induced damage to growth, chlorophyll metabolism, and photosynthesis by upregulating ascorbate–glutathione and glyoxalase cycle functioning in tomato

Abstract

Experiments were conducted to evaluate the role of exogenously applied nitric oxide (NO; 50 µM) and spermidine (Spd; 100 µM) in alleviating the damaging effects of Ni (1 mM NiSO46H2O) toxicity on the growth, chlorophyll metabolism, photosynthesis, and mineral content in tomato. Ni treatment significantly reduced the plant height, dry mass, and the contents of glutamate 1-semialdehyde, δ-amino levulinic acid, prototoporphyrin IX, Mg–prototoporphyrin IX, total chlorophyll, and carotenoids; however, the application of NO and Spd alleviated the decline considerably. Supplementation of NO and Spd mitigated the Ni-induced decline in photosynthesis, gas exchange, and chlorophyll fluorescence parameters. Ni caused oxidative damage, while the application of NO, Spd, and NO+Spd significantly reduced the oxidative stress parameters under normal and Ni toxicity. The application of NO and Spd enhanced the function of the antioxidant system and upregulated the activity of glyoxalase enzymes, reflecting significant reduction of the oxidative effects and methylglyoxal accumulation. Tolerance against Ni was further strengthened by the accumulation of proline and glycine betaine due to NO and Spd application. The decrease in the uptake of essential mineral elements such as N, P, K, and Mg was alleviated by NO and Spd. Hence, individual and combined supplementation of NO and Spd effectively alleviates the damaging effects of Ni on tomato.

Exogenous Hydrogen Sulfide Supplementation Alleviates the Salinity-Stress-Mediated Growth Decline in Wheat (Triticum aestivum L.) by Modulating Tolerance Mechanisms

“…In corroboration with these results, increased H 2 O 2 , MG, and lipid peroxidation has been reported by Ahanger et al [9,10], Hasanuzzaman et al [32], and Dawood et al [28]. At optimal concentrations, H 2 O 2 and MG are key in stress sensing and signaling; however, they impart damaging effects on growth and metabolism at higher concentrations [11,33]. Stressinduced increases in ROS can damage the membrane structure and alter its functioning, and HS supplementation can reduce ROS, as reflected in their declined lipid peroxidation and increased MSI.…”

“…Increased glyoxylase cycle activity due to HS treatment has also been reported in rice, resulting in significant decline in methylglyoxal content [13]. Maintaining lower concentrations of methylglyoxal prevents cells from cytotoxic effects, hence resulting in the maintenance of growth and metabolism [11].…”

“…It has been reported that the upregulation of these tolerance mechanisms provides stability to growth, photosynthesis, and enzyme functioning, and hence contributes to yield enhancement [8]. The upregulation of antioxidants [9,10], glyoxalases [7,11], and osmolytes [8], as well as the sequestering and compartmentalization of toxic ions [4], determines the potential of plant species to withstand the adversaries of salinity. From stress sensing to the elicitation of response, several molecules have key roles.…”

Exploring the synergistic effects of indole acetic acid (IAA) and compost in the phytostabilization of nickel (Ni) in cauliflower rhizosphere

“…During developmental stage, Ni toxicity may result in Fe deficiency, ultimately leading to white banding [ 8 ]. Notably, Ni has been found to adversely affect physiological attributes of plants i.e., chlorophyll contents owing to its interference with the uptake of different essential elements [ 9 ]. Similarly, Ni exposure has been reported to cause adverse impacts on vegetative and reproductive growth of plants flowering as well as total RNA contents [ 10 ].…”