Delivering Regional Extension in Qld Farming Systems - Central Queensland

The CQ Cotton Regional Extension project has been a key to the delivery of emerging, cutting edge research information and knowledge to the Central Queensland cotton industry. The direct relevance of southern research to cotton production under the conditions experienced in CQ always has been an issue which could be addressed through regional assessment and adaptation. The project links the national research to the region through development and extension, with a strong focus on the major industry production issues including but not limited to disease, Integrated Pest Management (IPM), soils, nutrition and integrated weed management. Susan Mass has supported the implementation of national industry-wide programs particularly the industry Best Management Practices program (myBMP). This project has successfully transitioned to a focus on delivering national outcomes in target lead areas as part of National Development and Delivery Team established by Cotton CRC, CRDC and Cotton Australia, while maintaining a regional extension presence for Central Queensland cotton & grain farming systems. Susan Mass has very effectively merged and integrated strong regional extension support to cotton growers in Central Queensland with delivery of industry extension priorities across the entire industry in the Development and Delivery Team model. Susan is the target lead for disease and farm hygiene. Recognising the challenges of having regionally relevant research in Central Queensland, this project has facilitated locally based research including boll rot, Bt cotton resistance management, and mealybug biology through strong collaborations. This collaborative approach has included linkage to Department of Environment and Resource Managmeent (DERM) groups and myBMP programs resulting in a high uptake in CQ.

Strategic tillage in no-till farming systems in Australia's northern grains-growing regions: I. Drivers and implementation

Development of no-tillage (NT) farming has revolutionized agricultural systems by allowing growers to manage greater areas of land with reduced energy, labour and machinery inputs to control erosion, improve soil health and reduce greenhouse gas emission. However, NT farming systems have resulted in a build-up of herbicide-resistant weeds, an increased incidence of soil- and stubble-borne diseases and enrichment of nutrients and carbon near the soil surface. Consequently, there is an increased interest in the use of an occasional tillage (termed strategic tillage, ST) to address such emerging constraints in otherwise-NT farming systems. Decisions around ST uses will depend upon the specific issues present on the individual field or farm, and profitability and effectiveness of available options for management. This paper explores some of the issues with the implementation of ST in NT farming systems. The impact of contrasting soil properties, the timing of the tillage and the prevailing climate exert a strong influence on the success of ST. Decisions around timing of tillage are very complex and depend on the interactions between soil water content and the purpose for which the ST is intended. The soil needs to be at the right water content before executing any tillage, while the objective of the ST will influence the frequency and type of tillage implement used. The use of ST in long-term NT systems will depend on factors associated with system costs and profitability, soil health and environmental impacts. For many farmers maintaining farm profitability is a priority, so economic considerations are likely to be a primary factor dictating adoption. However, impacts on soil health and environment, especially the risk of erosion and the loss of soil carbon, will also influence a grower's choice to adopt ST, as will the impact on soil moisture reserves in rainfed cropping systems. © 2015 Elsevier B.V.

Winter sowing for more reliable boll filling in Central Queensland

The Central Highlands region has a unique climate that presents both challenges and novel farming systems opportunities for cotton production. We have been re-examining the Emerald climate in a bid to identify opportunities that might enable the production of more consistent cotton yields and quality in what can be a highly variable climate. A detailed climatic analysis identified that spring and early summer is the most optimal period for boll growth and maturation. However, to unlock this potential requires unseasonal winter sowing that is 4 to 6 weeks earlier than the traditional mid-September sowing. Our experiments have sought answers to two questions: i) how much earlier can cotton be sown for reliable crop establishment and high yield; ii) can degradable plastic film mulches minimise the impact of potentially cold temperatures on crop establishment and early vigour. Initial data suggests August sowing offers the potential to grow a high yield at a time of year with reduced risk of cloud and high night temperatures during boll growth. For the past two seasons late winter sowing (with and without film) has resulted in a compact plant with high retention that physiologically matures by the beginning of January. Even with the spectre of replanting cotton in some seasons due to frost in August, early sowing would appear to offer the opportunity for more efficient crop input usage, simplified agronomic management and new crop rotation options during late summer and autumn. This talk will present an overview of results to date.

Response of irrigated cotton to applied nitrogen

Like all high yielding farming systems nitrogen (N) is a key component to their productivity and profitability and Australian irrigated cotton growers are tending to apply more N than is required for the level of lint yield that is being achieved. This suggests either over application of N or inefficient systems limiting the response of cotton to N inputs. To investigate this four replicated trials were established in commercial fields during the 2014/15 season. The trials were aiming to measure the difference in response of irrigated cotton to the application of N under flood and overhead irrigation systems. The application treatments utilized eight upfront rates of applied N, ranging from 0 N kg/ha to a maximum of 410 kg N/ha, with three of the fours trials receiving a growerdetermined in-crop application of N in the irrigation water. The two flood irrigation systems had lower lint yields from similar levels of N input compared to one of the overhead irrigated sites; the result from the second overhead site was impacted by disease. This paper discusses the response of plant N uptake, lint yield and fertilizer N recovery to N application..

BYGUM – a new tool for BarnYard Grass Understanding and Management

Weed management has become increasingly challenging for cotton growers in Australia in the last decade. Glyphosate, the cornerstone of weed management in the industry, is waning in effectiveness as a result of the evolution of resistance in several species. One of these, awnless barnyard grass, is very common in Australian cotton fields, and is a prime example of the new difficulties facing growers in choosing effective and affordable management strategies. RIM (Ryegrass Integrated Management) is a computer-based decision support tool developed for the south-western Australian grains industry. It is commonly used there as a tool for grower engagement in weed management thinking and strategy development. We used RIM as the basis for a new tool that can fulfil the same types of functions for subtropical Australian cotton-grains farming systems. The new tool, BYGUM, provides growers with a robust means to evaluate five-year rotations including testing the economic value of fallows and fallow weed management, winter and summer cropping, cover crops, tillage, different herbicide options, herbicide resistance management, and more. The new model includes several northernregion- specific enhancements: winter and summer fallows, subtropical crop choices, barnyard grass seed bank, competition, and ecology parameters, and more freedom in weed control applications. We anticipate that BYGUM will become a key tool for teaching and driving the changes that will be needed to maintain sound weed management in cotton in the near future.

Investigation into various fungicides and alternative solutions for controlling postharvest diseases in papaya fruit

In Australia, Sportak® (a.i., prochloraz) has been registered since the early 1980's for the postharvest control of both anthracnose and stem-end rots in papaya fruit, despite the persistence of fruit breakdown due to disease during transit and at market destinations. Consequently, the Australian papaya industry has been concerned over the efficacy of prochloraz and whether substitute or alternative solutions were available for better disease control, particularly during times of peak disease pressure. This study therefore investigated the effects of various postharvest treatments for disease control in papaya. Fruit were harvested at colour break from coastal farms in Far North Queensland and treated with commercial rates of various fungicides, including prochloraz, imazalil, thiabendazole and fludioxonil. Additional solutions known to inhibit disease were examined, including chitosan and carnauba wax both with and without ammonium carbonate (AC). Following treatment, fruit were ripened and assessed for quality over their shelf life. Fludioxonil when applied as a hot dip was found to be a more efficacious treatment for control of disease in papaya than prochloraz. The other fungicides were moderately effective, as both thiabendazol and prochloraz exhibited an intermediate response and imazalil was the least effective. Disease severity was lowest in fruit treated with AC followed by chitosan, whilst chitosan delayed degreening. Overall, the study found that hot fludioxonil provided an effective replacement of the currently registered chemical prochloraz, and that alternate solutions such chitosan and AC may also be beneficial, particularly for low chemical input farming systems.

A model to achieve sustainable improvement and innovation in organisations, industries, regions and communities

The achievement and measurement of improvements and innovations is not often an overt practice in the design and delivery of government services other than in health services. There is a need for specific mechanisms proven to increase the rate and scale of improvements and innovations in organisations, communities, regions and industries. This paper describes a model for the design, measurement and management of projects and services as systems for achieving and sustaining outcomes, improvements and innovations.The development of the model involved the practice of continuous improvement and innovation within and across a number of agricultural development projects in Australia and nternationally. Key learnings from the development and use of the model are: (1) all elements and factors critical for success can be implemented, measured and managed; (2) the design of a meaningful systemic measurement framework is possible; (3) all project partners can achieve and sustain rapid improvements and innovations; (4) outcomes can be achieved from early in the life of projects; and (5) significant spill-over benefits can be achieved beyond the scope, scale and timeframe of projects

Effect of sugarcane cropping systems on herbicide losses in surface runoff

Herbicide runoff from cropping fields has been identified as a threat to the Great Barrier Reef ecosystem. A field investigation was carried out to monitor the changes in runoff water quality resulting from four different sugarcane cropping systems that included different herbicides and contrasting tillage and trash management practices. These include (i) Conventional - Tillage (beds and inter-rows) with residual herbicides used; (ii) Improved - only the beds were tilled (zonal) with reduced residual herbicides used; (iii) Aspirational - minimum tillage (one pass of a single tine ripper before planting) with trash mulch, no residual herbicides and a legume intercrop after cane establishment; and (iv) New Farming System (NFS) - minimum tillage as in Aspirational practice with a grain legume rotation and a combination of residual and knockdown herbicides. Results suggest soil and trash management had a larger effect on the herbicide losses in runoff than the physico-chemical properties of herbicides. Improved practices with 30% lower atrazine application rates than used in conventional systems produced reduced runoff volumes by 40% and atrazine loss by 62%. There were a 2-fold variation in atrazine and >10-fold variation in metribuzin loads in runoff water between reduced tillage systems differing in soil disturbance and surface residue cover from the previous rotation crops, despite the same herbicide application rates. The elevated risk of offsite losses from herbicides was illustrated by the high concentrations of diuron (14mugL-1) recorded in runoff that occurred >2.5months after herbicide application in a 1st ratoon crop. A cropping system employing less persistent non-selective herbicides and an inter-row soybean mulch resulted in no residual herbicide contamination in runoff water, but recorded 12.3% lower yield compared to Conventional practice. These findings reveal a trade-off between achieving good water quality with minimal herbicide contamination and maintaining farm profitability with good weed control.