Assessment of AgNPs exposure on physiological and biochemical changes and antioxidative defence system in wheat ( Triticum aestivum L) under heat stress

Abstract

The present study was designed to check the role of silver nanoparticles (AgNPs) on physiological, biochemical parameters and antioxidants of wheat (Triticum aestivum L.) under heat stress. Plant extract of Moringa oleifera was used for AgNPs synthesis followed by characterization through UV-Vis spectroscopy, SEM, XRD and Zeta analyser. Heat stress was applied in range of 35-40°C for 3 hrs/ day for 3 days to wheat plants at trifoliate stage. Heat stress decreased the RWC (13.2%), MSI (16.3%), chl a (5.2%), chl b (4.1%) and TCCs (9.9%). Wheat plants treated with AgNPs showed significant increase in RWC (12.2%), MSI (26.5%), chl a (10%), chl b (16.4%), TCCs (19%), TPC (2.4%), TFC (2.5%), TASC (2.5%), SOD (1.3%), POX (1.5%), CAT (1.8%), APX (1.2%) and GPX (1.4%), under heat stress. Lower concentration of AgNPs (50 mg/l) decreased the sugar (5.8%) and proline contents (4%), while increase was observed in higher AgNPs concentrations. Overall, AgNPs treatment enhanced thermo-tolerance in wheat plants, but the mechanism of AgNPs action needs further investigation at genome and proteome level in wheat plants under heat stress.

Research Progress in Membrane Lipid Metabolism and Molecular Mechanism in Peanut Cold Tolerance

“…Antioxidant enzymes are located among different sites of plant cells and work together with ROS-generating pathways to maintain ROS homeostasis (Zhang et al, 2015; Nejat and Mantri, 2017; Iqbal et al, 2019). The transcription factor APETALA2/ethylene response factor (AP2/ERF) plays an important regulatory role in signal transduction of the plant responses to various stresses including low temperature (Sakuma et al, 2002), which confers cold tolerance by promoting polyamine turnover, antioxidant protection, and proline accumulation.…”

Silver nanoparticles and silver salt (AgNO3) elicits morphogenic and biochemical variations in callus cultures of sugarcane

“…7 C ). Hussain et al [56] and Iqbal et al [57] reported that the total protein content was obstructed by the presence of AgNPs. In addition, Mehrian et al [58] revealed variations in amino acids content in tomato plants treated with AgNPs compared with untreated plants.…”

“…According to Mishra et al [59] plants produce different types of osmolytes such as proline as a counter‐part to abiotic stresses and involved in stress tolerance through osmotic adjustment and ROS detoxification. Mohamed et al [60] and Iqbal et al [57] reported overproduction of proline in wheat plants. Similarly, Mehmood and Murtaza [61] observed an increase in organic solutes due to AgNPs in pea ( Pisum sativum L.) seeds.…”

“…Similarly, Mehmood and Murtaza [61] observed an increase in organic solutes due to AgNPs in pea ( Pisum sativum L.) seeds. It has been reported in the literature that proline concentrations increased several times under various stresses such as drought [62], salt [63], UV‐B stress [64], heat stress [57] and biotic stress [53] as compared to normal conditions. Complementary to osmo‐protective role of proline, few studies have highlighted that this molecule can help to retain redox balance in the cells [65].…”

“…Similarly, Ma et al [73] reported a profound increase in ROS production in Arabidopsis seedlings when exposed to CeO 2 and In 2 O 3 nanoparticles demonstrating oxidative stress clearly. According to Iqbal et al [57], the production of ROS takes place due to high metabolism in response to external stresses, as a result, plant cells elicited to produce antioxidant enzymes. Plants produced intracellular antioxidant (GSH) as their defence mechanism to minimise the lethal effects of ROS species inside the cell [4].…”