Combating biotic stresses in plants by synthetic microbial communities: Principles, applications and challenges

Abstract

Presently, agriculture worldwide is facing the major challenge of feeding the increasing population sustainably. The conventional practices have not only failed to meet the projected needs, but also led to tremendous environmental consequences.Hence, to ensure a food-secure and environmentally sound future, the major thrust is on sustainable alternatives. Due to challenges associated with conventional means of application of biocontrol agents in the management of biotic stresses in agroecosystems, significant transformations in this context are needed. The crucial role played by soil microbiome in efficiently and sustainably managing the agricultural production has unfolded a newer approach of rhizosphere engineering that shows immense promise in mitigating biotic stresses in an eco-friendly manner. The strategy of generating synthetic microbial communities (SynComs), by integrating omics approaches with traditional techniques of enumeration and in-depth analysis of plant-microbe interactions, is encouraging. The review discusses the significance of the rhizospheric microbiome in plant's fitness, and its manipulation for enhancing plant attributes. The focus of the review is to critically analyse the potential tools for the design and utilization of SynComs as a sustainable approach for rhizosphere engineering to ameliorate biotic stresses in plants. Furthermore, based on the synthesis of reports in the area, we have put forth possible solutions to some of the critical issues that impair the large-scale application of SynComs in agriculture.

Burkholderia gladioli strain KJ-34 exhibits broad-spectrum antifungal activity

“…Biocontrol is a traditional, effective, and sustainable solution for food security. The discovery of new microorganisms that can be used as biocontrol agents is attracting researchers' attention (Pradhan et al, 2022). In this study, we isolated and characterized biocontrol strain KJ-34, which exhibited high antifungal activity against a broad range of fungal phytopathogens.…”

Assembly and Function of Seed Endophytes in Response to Environmental Stress

“…This is likely due to the ease with which seed-associated bacteria can participate in both endogenous phytohormone regulation and external regulation to promote plant growth by enhancing plant adaptation and inhibiting pathogen infestation [ 69 , 75 ]. In addition, although the use of synthetic communities [ 109 , 110 ] rather than a single strain should be considered to explore the possible phenotypic characteristics and functions of seed endophytes based on omics, it is a major challenge to understand the interaction between seed endophytes and host plants and other microbes, which is a complex process that may depend on endophyte species, environmental conditions, and gene types of host plants. For example, the interaction of seed fungi and bacteria with arbuscular mycorrhizal fungi ( Rhizophagus irrigularis ) has a negative feedback effect on the growth of Trifolium repens , and this negative effect may be competition over resource allocation and temporal priority as well as the release of secondary metabolites [ 111 ].…”

Harnessing Emergent Properties of Microbial Consortia: Assembly of the Xilonen SynCom

“…Synthetic communities (SynComs) have emerged as valuable tools for establishing causal relationships between members (or their genes) and community functions (phenotypes) (42,43). These laboratory-assembled communities can be designed to represent natural communities but with reduced complexity (42), thereby enabling precise experimental manipulation aimed at generating microbial consortia for enhancing plant health and productivity (44)(45)(46). However, the design of simplified, tractable and ecologically relevant SynComs is still challenging (39)(40)(41).…”