Microbial Community Composition Reveals Spatial Variation and Distinctive Core Microbiome of the Weaver Ant Oecophylla smaragdina in Malaysia

Kah-Ooi Chua,Wai-Fong Yin,Hoi-Sen Yong,Wah-Seng See-Too,Sze-Looi Song,Kok-Gan Chan

doi:10.1038/s41598-018-29159-2

Abstract

The weaver ant Oecophylla smaragdina is an aggressive predator of other arthropods and has been employed as a biological control agent against many insect pests in plantations. Despite playing important roles in pest management, information about the microbiota of O. smaragdina is limited. In this work, a number of O. smaragdina colonies (n = 12) from Malaysia had been studied on their microbiome profile using Illumina 16S rRNA gene amplicon sequencing. We characterized the core microbiota associated with these O. smaragdina and investigated variation between colonies from different environments. Across all 12 samples, 97.8% of the sequences were assigned to eight bacterial families and most communities were dominated by families Acetobacteraceae and Lactobacillaceae. Comparison among colonies revealed predominance of Acetobacteraceae in O. smaragdina from forest areas but reduced abundance was observed in colonies from urban areas. In addition, our findings also revealed distinctive community composition in O. smaragdina showing little taxonomic overlap with previously reported ant microbiota. In summary, our work provides information regarding microbiome of O. smaragdina which is essential for establishing healthy colonies. This study also forms the basis for further study on microbiome of O. smaragdina from other regions.

Highlights

Oecophylla smaragdina (Fabricius, 1775), commonly known as weaver ant is an obligate arboreal species well distributed throughout Southeast Asia, Oriental regions of India and northern Australia[16,17]
We identified the core microbiota of 12 O. smaragdina colonies in Malaysia using 16S rRNA gene amplification followed by high throughput Illumina sequencing
Our findings revealed the common bacteria taxa associated with O. smaragdina workers and showed that its community composition is generally stable as 97.8% of over 2 million quality-filtered reads were clustered into only 16 major Operational taxonomic units (OTUs) which were assigned into 8 bacterial families (Supplementary Tables S2 and S4)

Summary

Introduction

Oecophylla smaragdina (Fabricius, 1775), commonly known as weaver ant is an obligate arboreal species well distributed throughout Southeast Asia, Oriental regions of India and northern Australia[16,17]. In studies that described the ability of O. smaragdina in protecting coconut Cocos nucifera from its pest Amblypelta cocophaga, the ant needs to compete for occupancy of palm trees with a codominant but not beneficial ground-nesting ant Pheidole megacephala (Fabricius, 1793). Efforts and attempts to increase the distribution and abundance of O. smaragdina, including to kill competing ants with insecticides has been suggested but not extensively practiced[21]. This is because to ensure O. smaragdina’s success as biological control agents, the ant’s competitive ability should be enhanced by establishing healthy colonies, and microbiota associated with O. smaragdina is believed to play a critical role in the host fitness. We assessed the spatial variation in the microbiota of O. smaragdina by performing comparison among colonies from different environments

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Results

Discussion

Conclusion