Investigation of Comparative Regulation on Antioxidant Enzyme System under Copper Treatment and Drought Stress in Maize (<i>Zea mays</i> L.)

Abstract

The present study was conducted to present the responses of drought-sensitive ‘Shemal’ and drought-tolerant ‘71MAY69’ maize cultivars under drought condition (20% Polyethylene glycol, -0.40 MPa) and three different copper concentrations (0.5 mM, 1 mM, 1.5 mM CuSO4.5H2O) for 5 days to determine the enzymatic responses of copper treatment in maize leaves.Copper treatments alone did not change stomatal conductance, relative water content, malondialdehyde, proline, hydrogen peroxide content and abscisic acid level according to control groups. Combined treatment (drought and copper) alleviated the damage of PEG- induced drought stress in maize leaves. Superoxide dismutase (SOD), catalase (CAT), glutatione reductase (GR) activity increased and glutathione -S transferase (GST) activity decreased, while ascorbate peroxidase (APX) activity didnot change under drought stress in the tolerant cultivar. SOD, CAT and APX were decreased and GST activities were increased while GR did not change in ‘Shemal’. Also SOD, APX and CAT activity increased by copper treatment alone in both cultivars. Otherwise combined treatment increased SOD, APX and CAT activity at all concentrations, but GR and GST activity increased only by (PEG+1.5 mM) treatment when compared with PEG treatment alone in sensitive ones. As a result, exogenous copper alleviated drought stress, while it induced an oxidative damage by increasing antioxidant enzyme activities differently from drought tolerance. Copper tolerance in maize is not a common response of its defense mechanism because of different response to copper and drought in the same cultivar.

Rice Straw Vermicompost Enriched With Cellulolytic Microbes Ameliorate the Negative Effect of Drought in Wheat Through Modulating the Morpho-Physiological Attributes

“…However, a non-significant increase with an increase in soil-applied cellulolytic-enriched vermicompost rates was also recorded for some traits. Similar to that, previous studies also showed that drought-stressed plants had higher canopy temperatures than non-stressed ones (Azarmi et al, 2008;Bowden et al, 2010;Cetinkaya et al, 2014;and Bai and Purcell, 2018). The highest canopy temperature was recorded in plants without vermicompost application under severe drought stress (30% FC) in both cultivars.…”

Effects of Vermicompost on Some Morphological, Physiological and Biochemical Parameters of Lettuce (Lactuca sativa var. crispa) under Drought Stress

“…Water-stressed plants showed a significant decrease in RWC in comparison to other treatments. Many studies showed that water stressed plants had lower RWC than non-stressed ones (Vassileva et al, 2011;Cetinkaya et al, 2014;Gulen et al, 2018). The highest reduction was recorded in plants without VC under severe DS (25% FC) (Fig.…”

“…1D). Important effects of DS on plants includes the decrease in leaf water potential and turgor loss, closure of stomata and decrease in internal CO2 concentration and CO2 assimilation (Rahbarian et al, 2011;Cetinkaya et al, 2014). VC limits stomata closure and increases CO2 supply necessary for photosynthesis due to fact that it has highly porous texture and high capacity for ventilation, proper drainage and water storage (Arancon et al, 2004).…”

Physiological Response of Upland Rice Varieties to Furrow with Organic Matter on Agroforestry System with Kayu Putih (Melaleuca leucadendra L.)

“…Cu is micronutrient that is important in plant metabolism like photosynthesis, respiration, protein and carbohydrate metabolism (Horvarth, 1990;Cetinkaya et al, 2014). The results of soil analysis show 3-20 ppm and that is low Cu content.…”