Changes in bumblebee queen gut microbiotas during and after overwintering diapause.

Area of Science:

• Entomology
• Microbiology
• Ecology

Background:

• Bumblebees are vital pollinators whose gut microbiota influences host health.
• Queen bumblebee gut microbes are crucial for establishing new colonies and seeding worker populations.
• Understanding microbiota dynamics during winter diapause is essential for bumblebee conservation.

Purpose of the Study:

• To investigate shifts in bumblebee queen gut microbiota structure and metabolic potential during and after winter diapause.
• To determine if glyphosate exposure affects post-diapause microbiota recovery.
• To assess the impact of diapause on microbial abundance and metagenomic data quality.

Main Methods:

• Queens of Bombus impatiens were subjected to diapause for up to 4 months.
• Samples were collected during diapause and after a 1-week recovery period, with some exposed to glyphosate.
• Whole-community shotgun metagenomic sequencing was employed to analyze microbiota composition and function.

Main Results:

• Core bumblebee gut phylotypes persisted, but Schmidhempelia and Snodgrassella were undetectable in late diapause and recovery.
• Microbiota metabolic potential remained stable despite taxonomic fluctuations.
• Glyphosate exposure did not alter post-diapause microbiota recovery.
• Microbial abundance and metagenomic data quality decreased significantly during diapause.

Conclusions:

• Bumblebee queen gut microbiota undergoes significant taxonomic changes during diapause, with potential implications for colony establishment.
• Metabolic functions of the gut microbiota remain largely consistent during diapause.
• Current glyphosate levels do not impede post-diapause microbiota recovery in bumblebee queens.
• Reduced microbial abundance during diapause impacts data quality, necessitating careful consideration in future studies.