Survey of invertebrate pests and beneficials harbouring in the chaff residue of harvest weed-seed controlled systems in

Background

Harvest weed seed control (HWSC) systems including chaff piles, chaff tramlining, chaff lining, are important alternate tactics to herbicide management of weeds. Adoption of these HWSC systems is increasing in the Southern Region and grain growers are observing an increase of invertebrates in paddocks where the HWSC chaff is present and there is concern to the potential risk of associated crop damage. Further adoption of HWSC systems may be deterred by the unknown impact of invertebrate pests in subsequent crops.

A GRDC research investment in WA (DAW1904-009RTX) determined that the geographic location of the paddock with chaff, influenced the abundance and composition of invertebrates, and that the presence of HWSC chaff increased the number of pest and natural enemy invertebrates present. This investment will quantify and interpret the pest and natural enemy invertebrate populations that harbour in the chaff residue of the HWSC systems; chaff lining, chaff tramlining and chaff piles and assess the associated crop damage. The research will be conducted in representative locations across GRDC Southern rainfall zones.

Investment description

This investment will expand the understanding of the species and the population numbers of invertebrate pests and natural enemies that harbour in HWSC chaff residue of GRDC's Southern region and assess the associated crop damage. The research outcomes will inform future initiatives on management of crop pests and address potential barriers to HWSC systems adoption by quantifying the risk to crop from invertebrate pests.

GRDC now seek to approach the market for a suitable applicant to provide applied field research and entomology expertise in invertebrate diagnostics and ecology.

*SAGI South are available for consultation during the development of your tender.

Outcome

By March 2024, growers and advisors of GRDC Southern rainfall zone will have access to current information on invertebrate pests and beneficial species harbouring in HWSC chaff residue system and the associated crop damage risk. This knowledge will lead to an increased confidence in adoption of appropriate HWSC techniques to manage weeds.

Outputs

Output 1 - By March 2024 growers and advisors will have access to current information on invertebrate pests and beneficial species harbouring in HWSC chaff residue systems in the GRDC Southern region.

Description:

• Surveillance of pest and beneficial invertebrate species population in 3 types of Harvest Weed Seed Control systems (chaff line, chaff tramlines and chaff cart dumps) and a control site without HWSC in representative locations across the GRDC Southern rainfall zones. Surveillance to be conducted 3 times during the season (post-harvest, seedling emergence and grain fill) over 2 seasons.
• Use of proven methodology from Western research investment DAW1904-009RTX and through consultation with SAGI – South on experimental design and data analysis as required.
• Observational survey of crop damage caused by invertebrate pests associated with HWSC chaff residue at seedling emergence and grain fill.
• May use data logger to capture location microclimate.
• Analysis and interpretation of the relationship between invertebrate biodiversity, environment and microclimate of HWSC systems to inform potential risk to crop and subsequent development of management strategies.

Output 2 - By March 2024, delivery of a communication package stemming from the research outcomes.

Description:

• A communications and extension plan will be developed in consultation with GRDC within the first 3 months of project commencement.
• The communications plan will ensure the outputs generated in this investment reach the intended audience and promote adoption of recommendations.
• Communication and extension will be delivered and promoted through existing GRDC, WeedSmart, National Pest Information Network and the contractor’s media channels and platforms.
• Communications may include development of publications to inform growers, agronomist and advisors.
• Extension may include presenting at GRDC Research Updates, Grower Network Meetings or in webinars or podcast interviews.