Omics-Based Mechanistic Insight Into the Role of Bioengineered Nanoparticles for Biotic Stress Amelioration by Modulating Plant Metabolic Pathways.

Madhuree Kumari,Alok Kumar Pandey,Ved Prakash Giri,Lalit Agarwal,Sanjay Dwivedi,Shipra Pandey,Shashank Kumar Mishra,Aradhana Mishra,Chandra Shekhar Nautiyal

doi:10.3389/fbioe.2020.00242

Abstract

Bioengineered silver nanoparticles can emerge as a facile approach to combat plant pathogen, reducing the use of pesticides in an eco-friendly manner. The plants’ response during tripartite interaction of plant, pathogen, and nanoparticles remains largely unknown. This study demonstrated the use of bioengineered silver nanoparticles in combating black spot disease caused by necrotrophic fungus Alternaria brassicicola in Arabidopsis thaliana via foliar spray. The particles reduced disease severity by 70–80% at 5 μg/ml without showing phytotoxicity. It elicited plant immunity by a significant reduction in reactive oxygen species (ROS), decreases in stress enzymes by 0.6–19.8-fold, and emergence of autophagy. Comparative plant proteomics revealed 599 proteins expressed during the interaction, where 117 differential proteins were identified. Among different categories, proteins involved in bioenergy and metabolism were most abundant (44%), followed by proteins involved in plant defense (20%). Metabolic profiling by gas chromatography–mass spectroscopy yielded 39 metabolite derivatives in non-polar fraction and 25 in the polar fraction of plant extracts. It was observed that proteins involved in protein biogenesis and early plant defense were overexpressed to produce abundant antimicrobial metabolites and minimize ROS production. Bioengineered silver nanoparticles performed dual functions to combat pathogen attack by killing plant pathogen and eliciting immunity by altering plant defense proteome and metabolome.

Highlights

Plant diseases possess a potential threat toward the productivity and quality of food and fiber, putting agriculture on a higher pressure to feed the ever-increasing population
Leaves were dipped in 5 ml of nanoparticles for 30 min and placed on 0.8% agar plates while leaves dipped in sterile water served as control
Antifungal activity of biosynthesized silver nanomaterial was tested in the model pathosystem of A. thaliana and A. brassicicola

Summary

Introduction

Plant diseases possess a potential threat toward the productivity and quality of food and fiber, putting agriculture on a higher pressure to feed the ever-increasing population. Several management practices have been employed to overcome this problem, but the phenomenon of multidrug resistance acquired by pathogen and climate change has made the situation more difficult (Juroszek and Tiedemann, 2015; Kim et al, 2016). Silver nanoparticles are potent antimicrobial agents, having proved their utility in medical applications (Mariana and De, 2019; Monir et al, 2019), their application in plant disease management is still in nascent stage (Ocsoy et al, 2013; Mishra et al, 2014). Silver nanoparticles exhibit multiple modes of actions of killing, which includes DNA unwinding, membrane disruption, changing permeability of membrane, and production of free radicals, making it very difficult for pathogens to acquire resistance against them (Verano-Braga et al, 2014; Kumari et al, 2017a,b)

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Conclusion