Bacterial Inhibition on Contributes to Microbiota Stability in .

Given the multiple roles of associated microbiota in improving animal host fitness in a microbial environment, increasing numbers of researchers have focused on how the associated microbiota keeps stable under complex environmental factors, especially some biological ones. Recent studies show that associated microbiota interacts with pathogenic microbes. However, whether and how the interaction would influence microbiota stability is limitedly investigated. Based on the interaction among , its associated microbiota, and one pathogen , the associated microbiota's response to the pathogen was determined in this study. Besides, the underlying mechanism for the response was also preliminarily investigated. Results showed that neither infect larvae nor did it colonize inside the associated microbiota, 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 during its invasion, while fungal microbiota did not inhibit conidial germination and mycelial growth of . According to the above results, individual dominant bacterial species were isolated, and their inhibition on conidial germination and mycelial growth of was reconfirmed. Thus, these results indicated that bacterial instead of fungal microbiota blocked conidia and stabilized the associated microbiota of larvae during invasion. The findings deepened the understanding of the role of associated microbiota-pathogen microbe interaction in maintaining microbiota stability. They may also contribute to the development of novel biological control agents and pest management strategies.