Comprehensive Transcriptome of the Maize Stalk Borer, Busseola fusca, from Multiple Tissue Types, Developmental Stages, and Parasitoid Wasp Exposures.

The Busseola Fusca Genome Consortium

doi:10.1093/gbe/evaa195

Abstract

Busseola fusca (Fuller) (Lepidoptera: Noctuidae), the maize stalk borer, is a widespread crop pest in sub-Saharan Africa that has been the focus of biological research and intensive management strategies. Here, we present a comprehensive annotated transcriptome of B. fusca (originally collected in the Western Province of Kenya) based on ten pooled libraries including a wide array of developmental stages, tissue types, and exposures to parasitoid wasps. Parasitoid wasps have been used as a form of biocontrol to try and reduce crop losses with variable success, in part due to differential infectivities and immune responses among wasps and hosts. We identified a number of loci of interest for pest management, including genes potentially involved in chemoreception, immunity, and response to insecticides. The comprehensive sampling design used expands our current understanding of the transcriptome of this species and deepens the list of potential target genes for future crop loss mitigation, in addition to highlighting candidate loci for differential expression and functional genetic analyses in this important pest species.

Highlights

The maize stalk borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae; Figure 1), is an important pest of cereal crops in sub-Saharan Africa
With the release of the genome and the publication of the first transcriptome, we have basic genomic information for this species
The current study expands on the geographical range of B. fusca populations surveyed; while the previously published transcriptome is based on tissues from individuals that originated in South Africa, our work focuses on individuals originating from Western Province, Kenya

Summary

Introduction

The maize stalk borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae; Figure 1), is an important pest of cereal crops in sub-Saharan Africa. Its impact on the food security and economic well-being of people has led to a number of studies into the physiology and ecology of the species (reviewed in Calatayud et al 2014). In particular, the identification of candidate genes related to important traits such as developmental timing, reproduction, insecticide resistance, adaptation to plant defense mechanisms, immunity, and chemoreception requires sampling multiple time points, exposures, and populations. This is relevant in B. fusca, where certain strains are known to be differentially vulnerable to infection by parasitoid wasps (Kfir 1995). This information, in turn, can inform or enhance management strategies (e.g., those developed for Plutella xylostella [You et al 2013])

Methods

Results

Discussion

Conclusion