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Abstract

Abstract-The submerged living larvae of Acentria ephemerella were fed in the laboratory with either M. spicatum or Potamogeton perfoliatus, two of their host plants. Larvae exhibited a reduced growth when fed M. spicatum, a freshwater angiosperm that contains high concentrations of tannins, secondary metabolites known for their herbivore-deterrent and antimicrobial properties. In this study, we investigated the influence of food-derived tannins on gut microbiota. Bacterial densities in the guts did not differ between the food regimes, ranging from 2.8 to 13.3 × 10 6 cells per gut. Gut bacteria were characterized with cultivation techniques and subsequent identification of the strains by molecular methods. We isolated 17 bacterial strains belonging to all subdivisions, i.e., we identified α-, β-, and γ -proteobacteria, Cytophyaga/Flavobacteria (CF) and several Gram-positive bacteria. All except one Gram-positive strain were found in the guts of larvae fed with P. perfoliatus. Gram-positive bacteria and bacteria of the CF cluster were more sensitive to polyphenol-containing extracts of M. spicatum in an agar diffusion assay than strains of the α-or γ -proteobacteria subdivision. Our results suggest an influence of food-derived tannins on gut microbiota in A. ephemerella.

The Multifunctional Roles of Polyphenols in Plant-Herbivore Interactions

“…by affecting the activity of wood rotting basidiomycete fungi in symbiosis with leaf cutter ants [151]. Tannins from Eurasian watermilfoil (Mtriophyllum spicatum L. Family: Haloragaceae) have been found to have allelochemical effect on the gut symbiont of water veneer (Acentria ephemerella Denis and Schiffermüller), thereby affecting their larval growth [158]. Although these examples provide an insight into the highly diverse and tightly regulated species-specific effects of polyphenols, investigating how different polyphenolic molecules act inside the insect body, their targets, and consequently their cellular and ecological effects is still a black box and needs further investigation.…”

Host Plant Species Influences the Composition of Milkweed and Monarch Microbiomes

“…Secondary plant compounds act not only as defensive tools against insect herbivores but can be highly effective against microorganisms as well. Secondary plant compounds may alter the microbial communities of both plants and herbivores, possibly due to antimicrobial effects that select against sensitive taxa while enriching for those capable of degrading or detoxifying plant defensive chemicals ( Walenciak et al, 2002 ; Gao et al, 2003 ; Keshavan et al, 2005 ; Davis and Hofstetter, 2012 ; Raffa, 2014 ; Hammer and Bowers, 2015 ; Mason et al, 2015 ; Pham et al, 2021 ; Rat et al, 2021 ). Although this study does not directly test for which plant microbes are affected by secondary plant compounds, our analysis (see Figure 3 ) identified differentially abundant bacterial families between milkweed species found in the rhizosphere (Dongiaceae, Moraxellaceae, Schlesneriaceae, Sneathiellaceae) and the phyllosphere (Phormidiaceae, Rhizobiaceae); which are potential candidates to further test for interactions with milkweed secondary compounds.…”

Impact of the Glucosinolate Sinigrin on Bacterial Communities in <i>Pieris rapae</i>

“…The observation that secondary plant metabolites can influence microbiota structure is not specific to glucosinolates or to Lepidoptera. For example, food-derived tannins, compounds found in high concentrations in aquatic angiosperms, were observed to influence the gut microbiota of the herbivorous aquatic moth, Acentria ephemerella, whereas the midgut microbiota of Schistocerca gregaria, the desert locust, and the termite, have also been influenced by secondary plant compounds [7] [8] [30]. While these specific phytochemicals can create perturbations to the microbiota, a measure of resilience can indicate the influence of plant compounds on the microbial community structure.…”