The considerable loss of crop productivity each year due to plant disease or pathogen invasion during pre- or post-harvest storage conditions is one of the most severe challenges to achieving the goals of food security for the rising global population. Although chemical pesticides severally affect the food quality and health of consumers, a large population relies on them for plant disease management. But currently, endophytes have been considered one of the most suitable biocontrol agents due to better colonization and acclimatization potential. However, a very limited number of endophytes have been used commercially as biocontrol agents. Isolation of endophytes and their screening to represent potential characteristics as biocontrol agents are considered challenging by different procedures. Through a web search using the keywords “endophytes as biocontrol agents” or “biocontrol mechanism of endophytes,” we have succinctly summarised the isolation strategies and different in vitro and in vivo biocontrol screening methods of endophytic biocontrol agents in the present review. In this paper, biocontrol mechanisms of endophytes and their potential application in plant disease management have also been discussed. Furthermore, the registration and regulatory mechanism of the endophytic biocontrol agents are also covered.

In the recent past, microbiome manipulation has emerged as a promising approach to improve plant growth performance by exploring the deep insight of plant–microbe interactions. The exploration of a plant microbiome either present on an ectosphere or endosphere can provide a far better understanding about the potential application of plant-associated microbes for the improvement of plant growth, protection from pathogen invasion, and tolerance to environmental stresses of a diverse nature. In this context, next-generation sequencing methods, omics approaches, and synthetic biology have made significant progress in plant microbiome research and are being frequently used to explore the intriguing role of plant-associated microorganisms. Despite the successfulness of conventional approaches, the incorporation of CRISPR/Cas9, RNA interference technology, rhizosphere engineering, microbiome engineering, and other manipulation techniques appear to be a promising approach to enhancing plant performance, and tolerance against biotic and abiotic stress factors. The present review presents the significance of plant microbe interaction, vital functional aspects, collaborative action, potential constraints, and finally the latest developments in bioengineering approaches destined for microbiome modulation with an objective to improve the performance of a host plant challenged with environmental stressors.