Microbiota associated with Deia antiqua

Given the multiple roles of associated microbiota in improving animal host fitness in a microbial world, increasing numbers of researchers have focused on how the associated microbiota keeps stable under complex environmental factors especially some biological ones. Recent researches have proved that associated microbiota would interact with pathogenic microbes. However, whether and how the interaction would influence microbiota stability is limitedly determined. Basing on the interaction among Delia antiqua, its associated microbiota, and one pathogen Beauveria bassiana, whether and how the associated microbiota would response to the pathogen were determined in this study. Results showed that B. bassiana neither infect D. antiqua larvae nor did it colonize inside the symbiosis, and both the bacterial and fungal microbiota kept stable during the interaction. Further experiments showed that bacterial microbiota almost completely inhibited conidial germination and mycelial growth of B. bassiana during its invasion, while fungal microbiota did not. According to the above results, dominant bacterial species were isolated, and they significantly inhibited conidial germination and mycelial growth of B. bassiana. These results indicated that bacterial instead of fungal microbiota blocked B. bassiana conidia and stabilized the associated microbiota of D. antiqua larvae during B. bassiana invasion. This work would deepen the understanding of the role of associated microbiota-pathogenic microbe interaction in maintaining microbiota stability, and contribute to developing novel biological control agents and pest management strategy.