NGN Water quality impacts on herbicide efficacy.

Description:

The quality of water used in spraying operations is crucial for achieving optimal weed control in cropping systems. Poor water quality can reduce the effectiveness of herbicides, which can significantly contribute to the development of herbicide resistance in weeds. This, in turn, negatively impacts profitability if spray applications do not effectively reduce the weed population. Growers have raised this issue at Northern Region NGN forums in 2023 and 2024, highlighting it as a matter of concern.

Enhancing growers' understanding of water quality test results will enable them to make more informed weed management decisions. This could involve either improving water quality or selecting appropriate herbicides based on the test results.

This investment aims to develop resources that support growers in understanding the importance of water testing in effective weed management. These resources will guide them on how to interpret water test results and use this knowledge to create a business action plan. Focus groups will be utilized to inform the development of these resources, ensuring that the outputs meet growers' needs and can be used in broader extension activities.

Outcome: By May 2027, a minimum of 60 growers, advisors, and spray contractors in the Northern Region will better understand the quality of their bore water. This knowledge will help them make informed decisions to improve herbicide efficacy.

Outputs:

Output 1.

Title: Focus Groups

Description: By May 2027, growers in key area who rely on bore water will understand the quality of water they have access to on property for use with herbicide mixing and options available to them to improve water quality and herbicide efficacy as well as improved decision making of herbicide choice.

Deliverables include:

•Establishment of a minimum of 12 targeted focus groups.

•Focus groups should be established in the Upper and Lower Namoi and Lachlan valleys of NSW and the Central Queensland, Balonne, Darling Downs and Border Rivers regions of Queensland - Water quality testing costs to be covered in the project operating expenses.

•Develop written materials that support the focus groups.

•Support growers to interpret water quality test results.

•Focus groups will improve understanding amongst participants of impact of water quality on herbicide efficacy.

•Assist growers to develop an action plan for their business that details potential infrastructure options and or herbicide options that best suit their available water and cropping system.

Focus group activities and feedback may also identify opportunities for this issue to be communicated to the broader industry through output 2.

Output 2.

Title: Communication and Extension.

Description: By May 2027, delivery of extension and communication activities targeted at growers, advisors and spray contractors to increase their understanding of water quality issues on herbicide efficacy and actions that can be taken to improve this.

Deliverables include:

•Minimum of 4 case studies to be developed that are derived from Output 1. Case studies to be promoted through GRDC communication channels.

•Conduct a webinar or similar that communicates water quality issues on herbicide efficacy.

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

•Develop written content from issues or opportunities raised in the focus group from output 1, that will be formatted, published, and promoted through communication platforms such as GRDC.