Gut Microbial Alterations in Diarrheal Baer's Pochards (Aythya baeri)

The structure and composition of gut microbiota correlate with the occurrence and development of host health and disease. Diarrhea can cause alterations in gut microbiota in animals, and the changes in the gut microbial structure and composition may affect the development of diarrhea. However, there is a scarcity of information on the effects of diarrhea on gut fungal composition and structure, particularly in Baer's pochard (Aythya baeri). The current study was performed for high-throughput sequencing of the fungal-specific internal transcribed spacer 1 (ITS-1) to detect the differences of gut mycobiota in healthy and diarrheal Baer's pochard. Results showed that the gut mycobiota not only decreased significantly in diversity but also in structure and composition. Statistical analysis between two groups revealed a significant decrease in the abundance of phylum Rozellomycota, Zoopagomycota, Mortierellomycota, and Kickxellomycota in diarrheal Baer's pochard. At the genus levels, fungal relative abundance changed significantly in 95 genera, with 56 fungal genera, such as Wickerhamomyces, Alternaria, Penicillium, Cystofilobasidium, and Filobasidium, increasing significantly in the gut of the diarrheal Baer's pochard. In conclusion, the current study revealed the discrepancy in the gut fungal diversity and community composition between the healthy and diarrheal Baer's pochard, laying the basis for elucidating the relationship between diarrhea and the gut mycobiota in Baer's pochard.

Isolation of Rhizosheath and Analysis of Microbial Community Structure Around Roots of Stipa Grandis

Background：The root zone microbial structure is particularly complex for plants with rhizosheaths, which may play an important role in the future agricultural sustainable development. However, one of the important reasons for restricting our study of rhizosheath microbial structure is that there is no definite method for rhizosheath separation. The aim of this study was to explore the isolation methods of rhizosheath and the diversity characteristics of microorganisms around the rhizosphere. In this study, we isolated the rhizosheath of Stipa grandis, a dominant species in desert steppe, and the microorganisms in the roots, root epidermis, rhizosheath, rhizosphere soil were extracted and sequenced by 16SrRNA and ITS.Results:The bacterial alpha diversity index was in the order rhizosphere soil > rhizosheath>root epidermis>endophytic, and the fungal alpha diversity index wasrhizosphere soil and rhizosheath> root epidermisand endophytic. There were significant differences in bacterial community structure between the root epidermis and endophytic, rhizosheath, rhizosphere soil. Different from bacterial community structure, the community structure of root epidermis fungi was similar to endophytic, but significantly different from rhizosheath and rhizosphere soil.Our method is feasible for separating plant rhizosheath and root epidermis.Conclusions：We suggest that the root epidermiscan act as the interface between the host plant root and the external soil environment.We will have to re-examine the biological and ecological significance of root sheath and microorganisms in rhizosheath, as well as the mechanism of its close relationship with plant root epidermis.This study will provide theoretical and technical guidance for the isolation of plant rhizosheath and the study of microorganisms in it.