Invisible Allies: The Role of Endophytic Entomopathogenic Microbes in Insect Pest Control

Abstract

Endophytic entomopathogenic microbes, including both bacteria and fungi, hold significant promise as biocontrol agents in sustainable pest management. While the biocontrol potential of entomopathogens are well-established, their role as mutualistic endophytes within plant tissues offers a relatively new avenue for enhancing pest suppression. The ability of these microbes to colonize plant tissues allows them to serve as internal defense agents against insect pests, while simultaneously promoting plant health and resilience to environmental stressors. Here, we explore the growing body of knowledge surrounding the use of endophytic entomopathogenic bacteria and fungi in pest management. These microbes contribute to pest control through direct effects on insect populations, such as mortality and feeding inhibition, as well as indirect plant-mediated mechanisms that enhance plant defenses. Additionally, endophytic entomopathogens provide a range of benefits to their plant hosts, including growth promotion, nutrient acquisition, and protection against pathogens. Despite the clear advantages of using endophytic entomopathogens, there remain key challenges to their widespread implementation. Environmental factors can influence their persistence and efficacy in the field, and their relatively slow mode of action compared to chemical pesticides presents a hurdle for rapid adoption in commercial agriculture. Non-target effects and the development of effective formulations to ensure consistent colonization are also areas that require further investigation. Addressing these challenges through continued research into the complex interactions between endophytes, insects, plants, and their environments will be essential for advancing the integration of endophytic entomopathogenic microbes into sustainable pest management systems.