Low Diversity Bacterial Community and the Trapping Activity of Metabolites from Cultivable Bacteria Species in the Female Reproductive System of the Oriental Fruit Fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae)

Zhanghong Shi,Hongyu Zhang,Lili Wang

doi:10.3390/ijms13056266

Abstract

Our goal was to identify the bacteria inhabiting the reproductive system of the female oriental fruit fly, Bactrocera dorsalis (Hendel), and evaluate the chemotaxis of B. dorsalis to the metabolites produced by the bacteria. Based on 16S rRNA-based polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), 18 operational taxonomic units (OTUs) were assigned to the five bacterial classes Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, Bacilli and Actinobacteria. Nine OTUs were assigned to Gammaproteobacteria, which was the most highly represented class. Enterobacteriaceae constituted the dominant family, and within this family, three genera and five species were identified, including Enterobacter sakazakii, Klebsiella oxytoca, Klebsiella pneumoniae, Raoultella terrigena and Enterobacter amnigenus. In this set, the first two species were the dominant components, and the latter three species were the minor ones. Finally, we found that the metabolites produced by R. terrigena, K. oxytoca and K. pneumoniae were attractive to the B. dorsalis adults, and in field studies, B. dorsalis adults were most attracted to K. oxytoca. Collectively, our results suggest that the female reproductive system plays an important role in the transfer of enterobacteria from the gut to fruit. Our data may prompt the development of a female-targeted population control strategy for this fly.

Highlights

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a destructive pest whose females lay eggs in the agricultural fruits of South East Asian and Pacific countries
By PCR-DGGE analysis, the clones were grouped into 18 operational taxonomic units (OTUs) (Figure 2) and assigned into five bacteria classes: Gammaproteobacteria (9 OTUs), Bacilli (5 OTUs), Betaproteobacteria (2 OTUs), Alphaproteobacteria (1 OTU) and Actinobacteria (1 OTU)
We identified a bacteria community consisting of the five classes Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, Bacilli and Actinobacteria in the female reproductive system of B. dorsalis adults

Summary

Introduction

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a destructive pest whose females lay eggs in the agricultural fruits of South East Asian and Pacific countries. The fly infests over 250 plant species, including economically important crops such as coffee, chili peppers, and carambola, peach, citrus, mandarin and mango fruit trees [1]. When the B. dorsalis larvae develop, the infested fruits rapidly deteriorate, leading to vast crop losses. Many pest-control strategies, such as methyl eugenol/protein baiting, the sterile insect technique and insecticide spraying, have been widely employed for decades, but due to the high fecundity and adaptability of this species, B. dorsalis is still not under effective control. The number of female flies has resulted in significant losses in the fruit industry; a novel control technique targeting female flies is urgently needed.

Objectives

Results

Discussion

Conclusion