ROS generated from biotic stress: Effects on plants and alleviation by endophytic microbes

Abstract

Aerobic living is thought to generate reactive oxygen species (ROS), which are an inevitable chemical component. They are produced exclusively in cellular compartments in aerobic metabolism involving significant energy transfer and are regarded as by-products. ROS have a significant role in plant response to pathogenic stress, but the pattern varies between necrotrophs and biotrophs. A fine-tuned systemic induction system is involved in ROS-mediated disease development in plants. In regulated concentrations, ROS act as a signaling molecule and activate different pathways to suppress the pathogens. However, an excess of these ROS is deleterious to the plant system. Along with altering cell structure, ROS cause a variety of physiological reactions in plants that lower plant yield. ROS also degrade proteins, enzymes, nucleic acids, and other substances. Plants have their own mechanisms to overcome excess ROS and maintain homeostasis. Microbes, especially endophytes, have been reported to maintain ROS homeostasis in both biotic and abiotic stresses by multiple mechanisms. Endophytes themselves produce antioxidant compounds and also induce host plant machinery to supplement ROS scavenging. The structured reviews on how endophytes play a role in ROS homeostasis under biotic stress were very meager, so an attempt was made to compile the recent developments in ROS homeostasis using endophytes. This review deals with ROS production, mechanisms involved in ROS signaling, host plant mechanisms in alleviating oxidative stress, and the roles of endophytes in maintaining ROS homeostasis under biotic stress.

WITHDRAWN: Green method for the analysis of nitenpyram and pymetrozine in tea

“…The PCX sorbent functions through the retention mechanism of cation exchange and reversed-phase characteristics. The ion exchange capacity of PCX cartridges is enhanced when an acidic environment is introduced for base compounds (Cao et al 2016;Sahu et al 2022). When the loading solvent is acidi ed (pH < 3), the nitrogen-containing chemical groups are protonated, resulting in the positively charged ions of pymetrozine and nitenpyram being retained by the PCX sorbent.…”

Levan differentially primes barley defence against infections by Fusarium graminearum, Rhizoctonia solani and Pyricularia oryzae

“…Both biological and abiotic stresses on plants have a common feature, that is, the generation and accumulation of ROS (Sahu et al., 2022). ROS accumulates in plants at the early stage of stress as a stress signal (Suzuki et al., 2012).…”

“…In order to avoid oxidative damage, plants have also evolved effective detoxification mechanisms to maintain the balance of ROS; for example, enzymatic reactions include superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) and non‐enzymatic reactions include alkaloids, carotenoids and phenols (Abd El‐Hameid & Sadak, 2020; Sadak & Bakry, 2020). Besides ROS, plants can regulate biological stress through different plant hormone pathways (Sahu et al., 2022). For example, Arabidopsis activates the salicylic acid (SA)‐mediated signal pathway against tobacco mosaic virus (Jia et al., 2016) while oilseed rape activates the jasmonic acid (JA)‐mediated signal pathway against Sclerotinia sclerotiorum (Yin et al., 2013).…”

Natural Plant Extract – Loganin: A Hypothesis for Psoriasis Treatment Through Inhibiting Oxidative Stress and Equilibrating Immunity via Regulation of Macrophage Polarization

“…44 Meanwhile, increasing evidence supports that M1 from psoriatic skin far exceed those from normal skin, thereby producing substantial ROS as well inflammatory cytokines that further initiate OS and switch on a series of pathogenic events in psoriasis. 9,11,22,23 The excessive and sustained stimulation of ROS in turn encourage the enhancement of intracellular oxidative metabolites and the impairment of antioxidant defense that contribute to more ROS accumulation, the formation of oxidized lipids and denatured protein, and the destruction of nucleic acids, finally resulting in cytotoxicity and damaging cells/tissues 57,58 Moreover, ROS aggressively activate transcription factors in KCs as well as VEGF-independent/VEGF-dependent pathways to facilitate psoriatic KCs hyperproliferation and abnormal angiogenesis in the dermis, contributing to psoriasis progression 59,60 Notably, ROS conversely induce and maintain M1 polarization via activating MAPK and NF-κB signals, which constantly stimulate pro-inflammatory genes expression in macrophages and aggravate OS damage to psoriasis individuals. 44,61…”