Effects of the Diet on the Microbiota of the Red Palm Weevil (Coleoptera: Dryophthoridae)

Abstract

Rhynchophorus ferrugineus, also known as the red palm weevil, is regarded as the major pest of palm trees. Although studies of the microbiota associated with this species have been performed in recent years, little attention has been dedicated to the influence of the diet in shaping the host bacterial community. Here, we investigated the influence of food sources (i.e. palm tissues vs apple based substrate) on the microbial diversity associated with RPW, which was compared with the microbiota associated with wild individuals of the sister species Rhynchophorus vulneratus. The bacterial characterization was performed using a culture independent approach, i.e. the 16S rRNA pyrotag, and a culture dependent approach for a subset of the samples, in order to obtain bacterial isolates from RPW tissues. The bacterial community appeared significantly influenced by diet. Proteobacteria resulted to be the most abundant clade and was present in all the specimens of the three examined weevil groups. Within Proteobacteria, Enterobacteriaceae were identified in all the organs analysed, including hemolymph and reproductive organs. The apple-fed RPWs and the wild R. vulneratus showed a second dominant taxon within Firmicutes that was scarcely present in the microbiota associated with palm-fed RPWs. A comparative analysis on the bacteria associated with the palm tissues highlighted that 12 bacterial genera out of the 13 identified in the plant tissues were also present in weevils, thus indicating that palm tissues may present a source for bacterial acquisition.

Effect of Different Lignocellulosic Diets on Bacterial Microbiota and Hydrolytic Enzyme Activities in the Gut of the Cotton Boll Weevil (Anthonomus grandis)

“…Host diet shapes the community structure and metabolic function of gut microbiota in different animals, including insects (Leser et al, 2000; Middelbos et al, 2010; Cardoso et al, 2012; Colman et al, 2012; Montagna et al, 2015). In termites, several studies have focused on how the dietary specialization determines the composition of the gut microbiota, and proposed that host diets shape termite gut microbiomes (Colman et al, 2012; Mikaelyan et al, 2015; Rahman et al, 2015).…”

“…There is extensive experimental evidence pointing out that the host diet shape the community structure and metabolic function of gut microbiota in different animals, including insects (Leser et al, 2000; Middelbos et al, 2010; Cardoso et al, 2012; Colman et al, 2012; Montagna et al, 2015). The existence of a core microbiota, which ensures the maintenance of the function, has been well documented in a variety of hosts.…”

Crustacean hemolymph microbiota: Endemic, tightly controlled, and utilization expectable

“…The presence of hemolymph microbiota was endemic; thus, local environmental factors, such as water condition and food supply, may also be key factors that influence the occurrence and composition of bacterial flora in some insects (Montagna et al, 2015). Interestingly, sex might be also a factor that affects the bacterial counts of the crustacean hemolymph.…”

Bacterial communities associated with the gut of tomato fruit borer, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) based on Illumina Next-Generation Sequencing

“…The gut microbiota of insects comprised of a wide variety of species, including bacteria, archaea, and eukaryea. Previously, the gut bacterial community of termite (Warnecke et al, 2007) has been studied in detail, similarly total bacterial community from intestinal tract of fruit fly, Bactrocera minax Enderlein, Diptera (Wang et al, 2014) and red palm weevil, Rhynchophorus ferrugineus (Olivier), Coleoptera (Montagna et al, 2015) have also been reported.…”