Microbes mediated induced systemic response in plants: A review

•Biotic stress leads to reduced crop yield and quality.•Induced systemic response (ISR) is one of the major mechanisms employed by the microbes in biocontrol.•Microbial elicitors such as volatiles, siderophores, rhamnolipids and lipopeptides play a major role in induce systemic response.•Molecular mechanisms of immunization in plants by microbial elicitors. Biotic stress affects economically important crop species and leads to quality and yield losses. Plants exhibit the ability of responding to the pathogen attack by synthesizing compounds which leads to either the inhibition or reduction of disease incidence. Plants live in close association with microbial communities. Microbes and their metabolites impact the health of the plants by supplying mineral nutrients, hormonal modulation and protection from the pathogenic organisms. Induced systemic response is one of the major mechanisms employed by the microbes in biocontrol. Beneficial microbes release certain compounds as elicitors in the rhizospheric region which are perceived by the plant roots as signals that increase the defense and resistance of the plants against the phytopathogens. The phytohormones such as ethylene, jasmonic acid, and salicylic acid are involved in regulation of the induced defense responses. The present review highlights the negative impact of the biotic stress on the plants and how induced systemic response is induced in the plants further discussing the role of the microbial elicitors in induced systemic response, their molecular mechanisms and hormonal regulation and draws the attention of the scientific community to explore new microbial elicitors as disease control alternatives.