Biocontrol Screening of Endophytes: Applications and Limitations

Abstract

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.

Screening and characterization of biocontrol bacteria isolated from Ageratum conyzoides against Collectotrichum fructicola causing Chinese plum (Prunus salicina Lindl.) anthracnose

“…However, increasing evidence suggests that biological control using beneficial microorganisms (bacteria, fungi, and yeasts) is a safe and promising approach for the management of plant diseases ( Liu et al, 2013 ; Radhakrishnan et al, 2017 ; Hong et al, 2022 ; Mehmood et al, 2023 ). Particularly, endophytic bacteria have been isolated from various medicinal plants, which have potential biological control properties ( Shurigin et al, 2021 ; Tripathi et al, 2022 ; Kashyap et al, 2023 ).…”

“…gloeosporioides dependent on various extracellular enzymes, cyclic tetrapeptides, and VOCs that inhibit spore germination and mycelial growth ( Choub et al, 2021 , 2022 ). However, endophytic microbes are considered one of the most suitable biocontrol agents because of their high colonization and adaptation potential compared to epiphytic microbes present above or outside the surface of plant tissues ( Kashyap et al, 2023 ).…”

Tiny Giants Endophytes in Sustainable Agriculture: Trends and Prospects

“…This part of the paper aims to critically address these issues and offer possible solutions, including novel biotechnological solutions, interdisciplinary collaboration, and support for bio-based products. However, the application of endophytes in agriculture faces various challenges, such as the low availability of microbial inoculants on the commercial market, regulatory concerns, and knowledge gaps regarding endophytes' ecological and physiological functions, some of which are mentioned in the literature [6,31,125]. Potential approaches to tackle these issues involve integrating research across different scientific disciplines, advancing biotechnological methods to enhance endophyte availability, and regulatory policies that support the widespread application of bio-based products [126].…”

In vitro screening of fungal endophytes from sandalwood (Santalum album) as antagonists to phytopathogens

“…Therefore, it is essential to approach the interpretation of in vitro screening results with caution and to complement them with in vivo studies to better assess the true potential of endophytic fungi in controlling phytopathogens in the natural context. Integrating both types of research can offer a more comprehensive understanding of the efficacy and practical applicability of these fungi in agricultural and environmental settings (Kashyap et al 2023).…”

“…Endophytes can outcompete phytopathogens by utilizing available resources more efficiently, denying them essential nutrients. Nonetheless, there are examples where endophytes may face challenges in effective competition, resulting in limited success in controlling phytopathogens (Kashyap et al 2023). This study can be a reference for further research in the agricultural sector.…”