NGN Post-emergent Broadleaf Weed Control in Chickpeas in Central Queensland

Description:

Broadleaf weed control in chickpeas is particularly challenging due to the lack of available post-emergent herbicides suitable for in-crop application. This issue was raised by growers at an NGN forum in Gindie, Queensland, where there was significant interest in exploring alternative options to the limited chemistry currently used by Central Queensland growers. In Central Queensland, growers face weed burdens in chickpea crops from species such as Mexican poppy, sow thistle, and wild turnip, for which the current standard grower practice of pre-emergent application of isoxaflutole, simazine or terbuthylazine are often ineffective. There is an opportunity to demonstrate the efficacy and suitability of recently registered pre-emergent herbicides within Central Queensland systems. Currently, growers in the region lack knowledge about their use. This investment will evaluate herbicides (pre and post emergent) currently registered for use in chickpea to assess their fit in the region and efficacy against local problematic weeds through replicated small plot field studies, with extension of this information to growers through field walks and presentation of results.

Outcome:

By May 2027, the impact of broadleaf weeds on chickpea production in Central Queensland is reduced through improved grower and adviser understanding of effective management options.

Outputs.

Output 1.

Title: Field studies for broadleaf weed control in Chickpea.

Description:

By May 2027, replicated small plot field studies that demonstrate the efficacy of a range of pre-emergent herbicides on difficult to control broadleaf weeds in Chickpea within a Central Queensland environment.

Deliverables include:

-A desktop review to identify currently registered pre- and post-emergent herbicides for use in chickpea.

-Conducting a minimum of 2 small plot replicated field studies in Central Queensland during both the 2025 and 2026 winter cropping seasons

-Field study protocols will be designed to evaluate the efficacy of pre- and post-emergent herbicides not in common use in Central Queensland identified through the desktop review. Protocols may also include herbicide mixtures. Data will be collected on weed emergence, survival, and crop yield.

-Weeds of focus are to be major broadleaf weeds impacting chickpea production in Central Queensland, including Mexican poppy, sow thistle and wild turnip.

-Trial reports of each field study are to be uploaded to GRDC Online Farm Trials.

Output 2.

Title: Communications and Extension.

Description:

By May 2027, delivery of extension and communication activities targeted at growers and advisers to increase understanding of management of broadleaf weeds in chickpea.

Deliverables include:

-Conducting a webinar or similar that communicates how to incorporate newer pre-emergent chemistries into weed management programs for controlling broadleaf weeds, drawing on results from the project (Output 1).

-Written content for a Factsheet targeted at growers and advisers covering the results from Output 1. This will be formatted, published, and promoted through communication platforms such as GRDC Communications and WeedSmart.

-Hosting of field walks at a minimum of two trial sites per year.

-Be available to provide this knowledge for GRDC Research Updates if requested.

-Be prepared to jointly host a National Grower Network meeting at field day events if requested.