Modulation of Plant Defense System in Response to Microbial Interactions

Abstract

At different stages throughout their life cycle, plants often encounter several pathogenic microbes that challenge plant growth and development. The sophisticated innate plant immune system prevents the growth of harmful microbes via two interconnected defense strategies based on pathogen perception. These strategies involve microbeassociated molecular pattern-triggered immunity and microbial effector-triggered immunity. Both these immune responses induce several defense mechanisms for restricting pathogen attack to protect against pathogens and terminate their growth. Plants often develop immune memory after an exposure to pathogens, leading to systemic acquired resistance. Unlike that with harmful microbes, plants make friendly interactions with beneficial microbes for boosting their plant immune system. A spike in recent publications has further improved our understanding of the immune responses in plants as triggered by interactions with microbes. The present study reviews our current understanding of how plant-microbe interactions can activate the sophisticated plant immune system at the molecular level. We further discuss how plant-microbe interaction boost the immune system of plants by demonstrating the examples of Mycorrhizal and Rhizobial association and how these plant-microbe interactions can be exploited to engineer disease resistance and crop improvement.

Interactive Effects of Mycorrhizae, Soil Phosphorus, and Light on Growth and Induction and Priming of Defense in Plantago lanceolata

“…Priming prepares plants for future attack without directly activating costly defenses ( Martinez-Medina et al, 2016 ). JA-dependent priming forms the basis of induced systemic resistance (ISR) triggered by a variety of beneficial soil microbes ( Van Wees et al, 2008 ; Zamioudis and Pieterse, 2012 ; Pieterse et al, 2014 ; Miozzi et al, 2019 ; Yu et al, 2019 ; Nishad et al, 2020 ). In addition to priming of JA-signaled defenses, MIR can also be simply mediated by induction of different classes of defense metabolites that has been widely observed in response to AMF colonization (e.g., Andrade et al, 2013 ; Vannette et al, 2013 ; Shrivastava et al, 2015 ).…”

Recent development and new insight of diversification and symbiosis specificity of legume rhizobia: mechanism and application

“…5c to d, to e). For '-N', the decreased application of chemical nitrogen fertilizer could remove the inhibition for the nodule formation and nitrogen fixation (Lim et al 2014;van Noorden et al 2016;Lin et al 2018), which could be caused especially by nitrate lower than 5 mmol l À1 in environments (Day et al 1989;Ohyama et al 2011;Irmer et al 2015;Sarr et al 2015;Nguyen et al 2019) (Fig. 5b).…”

“…4). These responses are also called MPMP-triggered immunity (MTI) (Nishad et al 2020), resulting in rapid calcium influx, reactive oxygen species (ROS) accumulation, cell wall alterations and defence gene expressions (Nishad et al 2020). In our recent studies, gene mutations involved in Mg 2+ transporter, endo-enzymes, intracellular proteins, flagellin and SH3-domain containing protein in Bradyrhizobium diazoefficiens USDA 110 endowed the strain to entry plant cells of S. flavescens and to develop nitrogen-fixing nodules, while the wild type strain could not (Liu et al 2018).…”

Plant Defense Responses to Biotic Stress and Its Interplay With Fluctuating Dark/Light Conditions

“…Plants possess a continuous ever-evolving armor of defense mechanisms to prevent the colonization of harmful pathogens ( Jones and Dangl, 2006 ; Nishad et al, 2020 ). Plants identify the signatures from the impeding pathogens and microbes via PAMPs, HAMPs, ETI, and PTI ( Zipfel, 2014 ; Cui et al, 2015 ; Peng et al, 2018 ) (see section “Biotic Stress and Plant Defense Responses”).…”