– Gut microbes break through the intestinal tract to activate the insect immune system –
Researchers) KIKUCHI Yoshitomo, Group Leader, Environmental Biofunction Research Group, Bioproduction Research Institute
- First elucidation of how insect gut microbes contribute resistance to pathogens.
- Identifies soil microorganisms that break through the gut epithelium and enter the body to activate the insect's immune system.
- Possibility to increase killing efficiency of biological pesticides (pest pathogens) by controlling intestinal microorganisms.
Gut microbes breach the intestinal epithelium and activate the insect's immune system.
A researcher in AIST, in collaboration with the Centre national de la recherche scientifique (CNRS) of France, has clarified for the first time how pest insects become resistant to disease through the power of gut microbes.
Biological pesticides with low environmental impact are attracting attention in order to achieve sustainable agriculture. Compared to chemical pesticides, biological pesticides (e.g. pathogenic microorganisms of pest insects) can reduce residues harmful to the human body and biodiversity, but to improve their effectiveness in controlling pests, it is still necessary to know more about the immune mechanisms of pests against pathogenic microorganisms. In this study, the authors investigated the immune mechanism of the soybean pest, Riptortus pedestris, and found that some gut microbes break through the epithelial cells of the gut and interact with phagocytes and immune cells (fat body) inside the stink bug, stimulating the systemic immunity. Furthermore, the authors found that stink bugs whose immune systems are activated by gut microbes show a high survival rate even when pathogens infect them. These findings open a new window in the field of insect immunity and are important for improving the insecticidal efficiency of biopesticides.
Amid recent concerns about the impact of chemical pesticides on biodiversity, pest control technology that does not rely on chemical pesticides is becoming increasingly important to realize sustainable agriculture. Under such a situation, the utilization of pathogenic microorganisms of pests is attracting attention as an alternative to chemical pesticides as a pest control method with low environmental impact.
In order to effectively utilize pathogenic microorganisms for pest control, a more detailed understanding of the immune mechanisms of pests against pathogenic microorganisms is needed. However, the immune system of pests remains unclear, and little is known about how pests counteract pathogens, especially in the agriculture fields.