Alimentary microbes of winter‐form Drosophila suzukii

Abstract

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a damaging pest of fruit. Reproductively diapausing adults overwinter in woodlands and remain active on warmer winter days. It is unknown if this adult phase of the lifecycle feeds during the winter period, and what the food source may be. This study characterized the flora in the digestive tract of D. suzukii using a metagenomics approach. Live D. suzukii were trapped in four woodlands in the south of England and their guts dissected for DNA extraction and amplicon-based metagenomics sequencing (internal transcribed spacer and 16S rRNA). Analysis at genus and family taxonomic levels showed high levels of diversity with no differences in digestive tract bacterial or fungal biota between woodland sites of winter-form D. suzukii. Female D. suzukii at one site appeared to have higher bacterial diversity in the alimentary canal than males, but there was a site, sex interaction. Many of the biota were associated with cold, wet climatic conditions and decomposition. This study provides the first evidence that winter-form D. suzukii may be opportunistic feeders during the winter period and are probably exploiting food sources associated with moisture on decomposing vegetation during this time. A core gut microbiome has been identified for winter-form D. suzukii.

High Diversity and Functional Complementation of Alimentary Canal Microbiota Ensure Small Brown Planthopper to Adapt Different Biogeographic Environments

“…Previous studies had also shown that gut symbionts in stinkbugs (Acrosternum hilare; Hemiptera: Pentatomidae) and harlequin cabbage bug (Murgantia histrionica; Heteroptera: Pentatomidae) are significantly influenced by temperature (Prado et al, 2010). A special core gut microbiome that was identified in the spotted wing Drosophila (Drosophila suzukii, Diptera: Drosophilidae) was also associated with a cold, wet climate (Fountain et al, 2018).…”

“…Although the tropical areas have high temperatures all year, they have two seasons of rain and drought and the highest annual temperature and precipitation. Latitude, temperature, and moisture are most important ecological factors that affect the diversity of insect gut microbiota (Kikuchi et al, 2016;Fountain et al, 2018). Previous studies had also shown that gut symbionts in stinkbugs (Acrosternum hilare; Hemiptera: Pentatomidae) and harlequin cabbage bug (Murgantia histrionica; Heteroptera: Pentatomidae) are significantly influenced by temperature (Prado et al, 2010).…”

Explorative Data Analysis of Drosophila suzukii Trap Catches from a Seven-Year Monitoring Program in Southwest Germany

“…While a high number of reproduction hosts is known from fruit sampling and lab studies, the complete feeding ecology is yet to be described. Early attempts to identify the ingested plant DNA and microbes in the guts of adult individuals have been successful [12,13]. Further studies using these techniques will help to understand the whole feeding ecology of this pest species.…”

Fly foregut and transmission of microbes

“…Yet, it has. Using a metagenomics approach, Fountain et al (2018) concluded that the microbiome of wintering adults from four different woodland areas in S. E. England showed no major differences in their microbiomes. In their study there was no snow cover preventing the flies from feeding on various substrates.…”

“…The idea of gut microbiome replenishing has been challenged by Pais et al (2018) and was previously discussed. A similar study to Fountain et al (2018) needs to be done on the microbiome of the crop (i.e. the crop has been ignored in this species) in a temperate area where snow covers the ground preventing feeding.…”