Bacterial communities in the gut of wild and mass-reared Zeugodacus cucurbitae and Bactrocera dorsalis revealed by metagenomic sequencing

Abstract

BackgroundInsect pests belonging to genus Bactrocera sp. (Diptera: Tephritidae) pose major biotic stress on various fruits and vegetable crops around the world. Zeugodacus and Bactrocera sp. are associated with diverse bacterial communities which play an important role in the fitness of sterile insects. The wild populations of melon fly, Zeugodacus cucurbitae (Coquillett) and Oriental fruit fly, Bactrocera dorsalis (Hendel) were collected from pumpkin and mango fields, respectively. The laboratory populations of Z. cucurbitae and B. dorsalis were mass-reared on bottle gourd and sweet banana, respectively. Bacterial communities present in the gut of wild and mass-reared mature (~ 12 days old) and newly emerged (< 1 h after emergence) male and female adults of Z. cucurbitae and B. dorsalis were assessed. We used Illumina HiSeq next-generation sequencing of 16S rRNA gene to profile the gut bacterial communities of wild and mass-reared mature and newly emerged Z. cucurbitae and B. dorsalis adults.ResultsWe found diverse bacterial composition in the gut of wild and mass-reared Z. cucurbitae (ZC) and B. dorsalis (BD) with varied relative abundance. Few taxonomic groups were common to both the species. The most dominant phyla in all samples of Z. cucurbitae and B. dorsalis adults were Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria. The phylum Proteobacteria occurred more in wild Z. cucurbitae (~ 87.72%) and B. dorsalis (~ 83.87%) as compared to mass-reared Z. cucurbitae (64.15%) and B. dorsalis (~ 80.96%). Higher relative abundance of Phylum Firmicutes was observed in mass-reared fruit fly than wild adults. Cyanobacteria/Chloroplast and Actinobacteria were also present with very low relative abundance in both wild as well as mass-reared melon fly and Oriental fruit fly. Enterobacteriaceae (61.21%) was dominant family in the gut of both wild and mass-reared adults. Providencia and Lactococcus were dominant genera with varied relative abundance in wild as well as in mass-reared mature and newly emerged fruit fly adults of both species. Some of the genera like Morganella and Serratia were only detected in mass-reared mature and newly emerged Z. cucurbitae and B. dorsalis adults. Principal Coordinate Analysis (PCoA) showed that fruit fly adult samples were grouped based on species and age of the adults while no grouping was observed on the basis of sex of the adult fruit fly.ConclusionsThe gut bacterial communities associated with wild and mass-reared mature and newly emerged adults of Z. cucurbitae and B. dorsalis showed variation that depends on species and age of the insects. Understanding the gut microbiota of wild and mass-reared Z. cucurbitae and B. dorsalis using high throughput technology will help to illustrate microbial diversity and this information could be used to develop efficient mass-rearing protocols for successful implementation of sterile insect technique (SIT).

Bacterial Communities in Three Parts of Intestinal Tracts of Carpenter Bees (Xylocopa tenuiscapa)

“…Porphyromonas gingivalis has been shown to increase the metabolic inflammation risk and autoimmune disorders in mice [ 50 ]. Members of the family Flavobacteriaceae were identified in melon flies, Zeugodacus cucurbitae [ 51 ] as well as in the guts of honey bees [ 17 ]. The Flavobacteriaceae_unclassified OTU from this study ( Figure 6 ) was related to Apibacter mensalis , which was isolated from Bombus lapidarius [ 52 ], and Apibacter adventoris isolated from honey bees and bumble bees [ 53 ].…”

“…However, Bifidobacterium , Dysgonomonas and family Pseudomonadaceae were found to be predominant only in the hindgut. Dysgonomonas had been identified in many insects’ guts [ 51 , 54 , 55 ]. It is involved in lignocellulose degradation.…”

Comparison of gut microbiota of healthy and diseased walking sticks, Phasmotaenia lanyuhensis

“…The microbiota of several insect species have been described to unravel the bacterial communities of the intestinal tract in insects, including Dipteran ( Zeugodacus cucurbitae, Bactrocera dorsalis, Anopheles stephensi , and Aedes albopictus etc. ; Hadapad et al, 2019; Villegas & Pimenta, 2014; Wei et al, 2017), Lepidopteran ( Bombyx mori , and Agrotis segetum etc. ; Chen et al, 2018; Sevim et al, 2010), and Hymenopteran ( Megachile centuncularis, Megaphragma amalphitanum , and different honey bee [ Apis mellifera ] subspecies etc.…”

“…Studies of insect gut microbiota have shown that gut microbiota may vary between insect species, their life stages (Hadapad et al, 2019; Villegas & Pimenta, 2014) or differences in feeding habit, especially for phytophagous insects (Chen et al, 2018; Lim & Ab Majid, 2020; Shelomi et al, 2013). Many studies have indicated that the insect gut microorganisms plays an important role in the development, digestion, metabolism, reproduction, immunity as well as many other physiological functions of their hosts (Chen et al, 2018; Hadapad et al, 2019; Pérez‐Ruiz et al, 2015; Skrodenytė‐Arbačiauskienė et al, 2019). The fact that exogenous bacteria may affect the lifespan of fruit fly ( Drosophila melanogaster ) further implicated the importance of gut microbiota in environmental fitness of the insect host (Brummel et al, 2004).…”

“…The fact that exogenous bacteria may affect the lifespan of fruit fly ( Drosophila melanogaster ) further implicated the importance of gut microbiota in environmental fitness of the insect host (Brummel et al, 2004). The correlation between nutrients (food source) and microbiota composition provides probiotics benefit to their insect hosts and the removal of these microorganisms might be a new strategy for pest control (Chen et al, 2018; Hadapad et al, 2019; Pérez‐Ruiz et al, 2015; Shelomi et al, 2013).…”