Nickel Toxicity Induced Changes in Nutrient Dynamics and Antioxidant Profiling in Two Maize (Zea mays L.) Hybrids

Abstract

Nickel (Ni) is among the essential micronutrient heavy metals utilized by plants. However, an elevated level of Ni causes serious concerns for plants’ physiology and their survival. This study evaluated the mechanisms influencing the growth, physiology, and nutrient dynamics in two commercial maize hybrids (Syngenta and Pioneer) exposed to Ni treatments in hydroponics nutrient solution (NS). Seedlings were raised in plastic trays with quartz sand, and subsequently transferred to Hoagland’s NS at the two leaves stage. After three days of transplantation, Ni levels of 0, 20, and 40 mg L−1 were maintained in the nutrient solution. After 30 days of Ni treatments, seedlings were harvested and different growth, physiological, and nutrient concentrations were determined. The results showed that with increasing Ni concentration, the growth of maize hybrids was significantly reduced, and the maize hybrid, Pioneer, showed significantly higher growth than that of Syngenta at all levels of Ni. Higher growth in Pioneer is ascribed to elevated levels of antioxidant enzymes (SOD, CAT, GR, APX, and POX), lower damage to cellular membranes (i.e., higher MSI and lower MDA), and higher tissue nutrient concentrations (N, P, K, Ca, Mg, Fe, Mn, Zn, and Cu). Furthermore, the maize hybrids showed a difference in nutrient translocation from root to shoot which could be one of the factors responsible for differential response of these hybrids against Ni treatments.

Physiological, photochemical, and antioxidant responses of wild and cultivated Carthamus species exposed to nickel toxicity and evaluation of their usage potential in phytoremediation

“…Excessive Ni causes reduction of chlorophyll and carotenoid contents, generation of free radicals, lipid peroxidation, disruption of cell structure, reduction in physiological functions, alteration of many enzymatic activities, destruction of photosynthetic protein complexes and chloroplast structure, dehydration (wilting), and consequently lower biomass production and yield (Sachan and Lal, 2017;Batool, 2018;Amjad et al, 2020). Generation of reactive oxygen species (ROS) enchanced by nickel at elevated levels and this over-production and accumulation of ROS that could not be scavenged may cause damage to several critical bio-molecules like lipids, proteins and nucleic acids in plant tissues (Gajewska and Skłodowska, 2007).…”

Distribution of nickel (Ni) in peatland situated alongside mineral soil derived from ultrabasic rocks

“…Mg (Table 3), relying on mass action, may inhibit Ni absorption by plant roots. According to Jiang et al (2017) and Amjad et al (2020), Mg had an antagonistic effect on Ni in the root zone. High total Ni would not cause hazardous effects for human and animal health due to its low availability at the near-neutral pH of mineral soil (Banerjee & Roychoudhury, 2020;Gonnelli & Renella, 2013).…”

Response of Three Greek Populations of Aegilops triuncialis (Crop Wild Relative) to Serpentine Soil

“…The performance of Lefkada and Preveza populations was higher without stress, while that of Aetolia-Acarnania maintained stable WUE in both soil types. The Aetolia-Acarnania population may have evolved a mechanism to withstand the serpentine stress [ 62 ], and/or is preadapted to grow under these specific conditions [ 22 ]. This result was also verified from the shoot/root ratio, which was more or less stable in the Aetolia-Acarnania population (NS= 3.84, S = 3.67), while it decreased 2-fold in the other two populations.…”

“…The pH of the serpentine soil is lower than 6.7, and the Ni compounds present in soil are relatively soluble [ 67 ]. The nickel stress influenced, as discussed above, the photosynthetic performance and presumably the plant nutrient status [ 62 ].…”