The broad aims of CCC CRC 5.2.03 ‘Delivering science to agribusiness: Smart approaches to cotton irrigation management’ were to; conduct irrigation research for emerging crop management issues and alternative cotton cropping systems; provide industry with an enhanced version of HydroLOGIC; and document a decision framework for integrating irrigation management tools. This project formed a key application and feedback link within the Cotton Management Support System Team, which developed targeted, cotton specific management tools for the Australian industry. This project also supported the CSIRO Plant Industry water research team of Mr Stephen Yeates (scientific development), Mr Dirk Richards (DSS development and application) and Mr James Neilsen (plant water relations).

Key research findings and outcomes were:

* Bollgard water use and scheduling

* Extraction patterns and the depth of rooting were similar in the Bollgard and conventional treatments by the end of the season.

* Bollgard®II had the potential to use less water whilst maintaining a yield advantage.

* Bollgard®II may be more sensitive to larger deficits (>55-60% PAWC), late in flowering and should be watered before conventional fields.

* A reduction in gross and irrigation water use efficiency was only found in Bollgard®II where moisture stress was experienced at or close to cut-out.

Application and use of HydroLOGIC in the industry

* Feedback from HydroLOGIC trial co-operators and users indicated a mixture of strategic and tactical use including; area to plant depending on water available; confirming scheduling decisions (consultants); benchmarking crop water use after harvest. A key application of the software was late in the season and when determining the last irrigation, with HydroLOGIC often indicating that the final irrigation was not required.

* HydroLOGIC user surveys indicated great value in this decision support tool with:

* 36% of respondents using the software to compare water use across farms,

* 44% of respondents finding the software easy to use, while recognising that the tool addresses complex issues and this requires significant training,

* 50% of respondents finding the data required by the software easy to collect,

* 78% of respondents saw HydroLOGIC fitting into their enterprise, and

* 60% of respondents indicating their wanted to learn more about HydroLOGIC.

* The greatest value in HydroLOGIC was in the areas of limited water (18%), irrigation scheduling (11%) and first irrigation (8%).

Documentation and integration of irrigation decision tools

* Research over two seasons demonstrated the value in using the Irrimate™, WaterTrack™, and HydroLOGIC tools to assist in separate aspects of water management. These experiments indicated the combined use of these products can result in significant water savings through improved irrigation efficiency, optimised water scheduling, identification of on-farm losses, and changes in farm management and infrastructure.

* All tools provided good commercial estimates of crop water use and use of any would result in better irrigation practice.

Research results from this project were successfully communicated to the Australian cotton industry via industry publications, media release, presentations and all other relevant media. An essential component of the projects success was the close collaboration with commercial cotton growers, consultants and the Cotton CRC extension network.