Application of super absorbent polymer and ascorbic acid to mitigate deleterious effects of cadmium in wheat

Abstract

The growing use of chemical fertilizers, insecticides and pesticides can cause potential contamination with heavy metals to soil and groundwater, posing environmental and health threats. Heavy metals can also affect crop yield. A greenhouse experiment was conducted to explore the role of ascorbic acid foliar application and soil-applied super absorbent to mitigate adverse effects of cadmium (Cd), in terms of biochemical parameters in wheat. The experiment was installed in a completely randomized design, with treatments arranged in a factorial scheme with three levels of super absorbent polymer (0 g kg^-1, 4 g kg^-1 and 8 g kg^-1 of soil) by three levels of ascorbic acid (0 mM, 50 mM and 100 mM), with four replicates. The Cd contamination caused a significant increase in the accumulation of Cd in leaves and seeds, as well as in antioxidant enzymes activity and lipid peroxidation. It also decreased seed weight and chlorophyll content in wheat plants. The super absorbent increased seed yield (22.68 %), seed weight (19.31 %), chlorophyll (27.97 %) and ascorbic acid content (65.51 %), while it reduced the Cd accumulation in leaves (34.27 %) and seeds (32.97 %), as well as antioxidant enzymes activity and lipid peroxidation (43.77 %). Similar results were found when ascorbic acid was applied. Ascorbic acid increased seed yield, seed weight and chlorophyll content by 12.62 %, 17.66 % and 13.17 %, respectively. As a result, the super absorbent polymer and ascorbic acid could improve the survival capacity and yield of wheat plants in response to Cd contamination in the soil.