Viruses to aid biological control of major root-feeding pests of sugarcane

Summary

Australia’s $1.7 billion sugar industry is threatened by severe root-feeding pests such as canegrubs and soldier flies. There are no effective control strategies for soldier flies and reliance on pesticides for canegrub control has severe negative impacts on the industry and the wider environment, rendering it unsustainable. This project will innovate new biopesticides for these pests by identifying novel naturally occurring insect-specific viruses using cutting-edge genomics and evaluate the efficacy of other entomopathogenic viruses. Expected outcomes include the development of a new tool for an environmentally safe biological control of these devastating pests. This will provide significant benefits to sugarcane growers, leading to economic gains and reducing environmental risk.

Objectives

• Application of metagenomics to identify novel entomopathogenic viruses in key root-feeding pests of sugarcane (soldier flies and canegrubs).
• Assessment of the efficacy of recently identified and imported insect pathogenic viruses against the major sugarcane pest, the greyback canegrub.
• Evaluation of the prevalence and geographic distribution of these naturally occurring insect-specific viruses in the greyback canegrub populations and evaluation of their pathogenicity against the pest.
• Determination of feasibility of deploying these viruses as effective commercial biocontrol agents.

Expected Outputs

(1) Identification of new biological control agents by i) assessing the efficacy of recently identified and imported entomopathogenic viruses against the greyback canegrub ii) improving our knowledge of insect-specific viruses of root-feeding pests of sugarcane, iii) investigation of the impact of these insect-specific viruses on the greyback canegrub. These will provide a better understanding of the potential interactions between these viruses and their hosts, potentially leading to identification of new biological control agents.

(2) Identification of novel plant viruses that are a potential biosecurity risk through sequencing insect gut content which feed on infected plant materials.

Expected Outcomes

The outcomes of this research will make significant contributions to the biocontrol of economically important root-feeding pests and establish a biosecurity tool for exploring existing viruses in sugarcane fields. The target audience of this research is the Australian Sugar industry who will benefit by having (i) an alternative option for control of canegrubs in the event of imidacloprid having restricted use in the future and (ii) a new approach to managing soldier fly which cannot currently be controlled with insecticides or deployment of less susceptible sugarcane varieties. Consequently, the long-term aim of this project is to reduce economic losses due to these pests and reduce the industry’s reliance on chemical insecticides.
From a broader perspective, the outcomes will have important implications for our understanding of virus evolution, providing a basis for preventing and managing plant health threats. The outcomes of this project will enhance SRA’s intellectual position in this field by providing potential research training and opportunities for growers and students. It will improve industry capability to develop alternative management recommendations to cane growers and other stakeholders.

SRA PROJECT CONTACT: Dr Stephen Mudge

RESEARCH AGENCY: The University of Queensland

CHIEF INVESTIGATOR: Dr Kayvan Etebari

PROJECT NUMBER: 2022/016

END DATE: 1/08/2027