Dryland group of concerned growers * Central Queensland early planting trial and field walk * Weeds Update * Nitrogen trials *What is happening at ACRI

The majority of Australia’s cotton producing soil is grey or black vertosols which have high clay content and are naturally prone to waterlogging following heavy rain or surface irrigation. Waterlogging events can lead to the loss of the excess applied nitrogen, these losses have been reported to be up to 50-100 kg N/ha (Rochester, 2003). Cotton (Gossypium hirsutum) production in Australian relies heavily on the application of irrigation water, and therefore there are many possible events for large nitrogen losses within a single growing season. Poor irrigation management or old inefficient irrigation infrastructure would also increase the potential nitrogen lost from an irrigation system. Janat (2008) found that modern irrigation application methods (such as drip irrigation) could improve Water Use Efficiency (WUE) by up to 30%.

The findings of this project showed that cotton management strategies influence the nitrogen cycle within an irrigated cotton system. Management options such as switching the furrow that is irrigated, the volume of water applied during an irrigation event and optimising nitrogen and water application, influenced the crop uptake of nitrogen and the amount of nitrogen (and its associated gases, such as nitrous oxide) lost from the system. Of the 36 kg N/ha that was lost from irrigation tail water through the cotton season 50% was lost at the first irrigation event. Developing strategies and best management practices (BMP) to reduce the effect of the first irrigation would have a significant impact on reducing the emissions from an irrigated cotton farm.

The agronomic management options that were investigated in this project could be applied with little to no impact on the farming operation. Such as irrigating down the furrow that had the fertiliser direct drilled and increasing the volume of applied water in the first irrigation event. These management options reduced the nitrogen lost in the tail water (up to 50%), while importantly had no impact on farm productivity (cotton yield).

Cotton consultants have been reluctant to monitor levels of egg parasitisin, primarily because of the tiine involved in collecting eggs. A new ratio, called the Beneficial Impact Ratio (BIR) was proposed to assist consultants in understanding in-field mortality due to

egg parasitoids without having to collect eggs. The BIR is the ratio of young larvae (Vs+S) to eggs. IdealIy the egg counts that are used in the BIR calculation should be from counts that were completed 2-4 days prior to the larval counts. However same day counts call be used to estimate in-field egg and young larval mortality. The lower the BIR the better, e. g. a BIR of almost zero was recorded when the levels of egg parasitisim were high.

On farm sorghum appeared to affect the abundance of egg parasitoids in nearby cotton, as high levels of egg parasitism were found in the sorghum immediately prior to those recorded in the cotton. There were also several plantings of sorghum on the farm. This sorghum provided a regular supply of eggs that supported substantial populations of Trichogramma.

The unsprayed INGARD cotton yielded just as well as the sprayed INGARD because:

- The Bt. toxin in the plant was effective against very small larvae early-mid season.

- The populations of beneficial species built up in the absence of chemical sprays. High numbers of predators (over 20/m) were recorded late season.

-Trichogramma were abundant from mid-late January onwards. Cotton plants have a natural ability to compensate for fruit loss.

The above factors combined represent successful, sustainable IPM.Intervention with chemical insecticides is not always required.

The success of IPM depends on not disrupting parasitoids and predators with chemicals. It is not enough to go soft early, because beneficials really come to the fore until mid-late season. If you are serious about IPM you must strive to avoid multiple applications of organophosphates and synthetic pyrothroids because they are extremely disruptive to beneficials, including Trichogramma. The impact of Trichogramma on the Darling Downs will become more noticeable as the use of broad spectrum chemical sprays throughout the region declines. Some insecticides, such as Dipel and Gemstar, are safe on Trichogramma, and should be used to control heliothis larvae whenever possible. All cotton growers and consultants should try to collect eggs and develop an appreciation for the Trichogramma, they are amazing little wasps!

The phosphorus dynamics of dryland cotton production require further elucidation, particularly the role of residual fertiliser P and mycorrhizal infection in yield. Incitec Pivot Ltd., in collaboration with independent researchers, has conducted a long term farming systems experiment at Tulloona , NSW , since 1995. The experiment is a complete randomised block, split plot, design with the treatments being 0 , 10, 20 kg/ha P and 0, 30, 60 , 90, 120 kg/ha N : and all permutations of the above. Nutrients, as urea and MAP, have been applied either pre or at plant for each crop planted, and rotations have included, sorghum , mungbean, wheat, chickpeas, and barley, throughout the duration of the project. The site is responsive to both N and P, with background Colwell P values > 10mg/kg, and with soil N levels varying depending on fallow mineralisation.

For the 2014/15 summer the rotation crop chosen for the site will be raingrown cotton. This will follow rain grown wheat sown June 2013. There has previously been very little previous experimentation investigating performance of raingrown cotton under these scenarios, and in this region. With soil test Colwell P values showing residual soil P levels ranging from 10 mg/kg P where no P has been applied, to 98 mg/kg following annual 20 kg P/ha applications.

This provides an ideal, and unique, scenario to investigate cotton crop performance under a range of residual P values, but also to investigate whether applied fertiliser P at sowing is providing a crop response or if labile P being released into solution is in fact the primary source of P. This experiment will also assist with validation of soil test critical values investigating current soil P test extraction methods such as Colwell P, BSES P, and less commonly used on Grey Vertisols DGT P. Core sampling throughout the trial will also allow quantification of the effect of P status on mycorrhizal colonisation of cotton following a 12 month fallow. the full report is available.

CottonMap is currently an ongoing annual investment.

The Cotton Field Awareness Map pinpoints the location of cotton fields, to assist in minimising off-target damage from downwind pesticide application, particularly during summer fallow spraying. The CottonMap is an industry initiative, which the farming community from farmers to consultants and contractors are encouraged to use. The map is a joint collaboration between Cotton Australia, Cotton Research and Development Corporation (CRDC), Grains Research and Development Corporation (GRDC) and Nufarm Australia Limited, developed to meet industry needs.

2014-15 was the first season where the area mapped on CottonMap equated to 100% of the

planted hectares for the season, however the figure of >100% mapped indicates a need to increase accuracy of the program. Cotton Australia have focussed extension efforts to improve this. Late mapping has been identified as an issue.

2015 marked 25 years of CRDC. In this special publication, CRDC takes a look back at 25 years of delivering research, development and extension (RD&E) outcomes for the benefit of Australia’s cotton growers, the cotton industry and the wider community.

This publication outlines the 25 major achievements in cotton RD&E over the past 25 years: 25 key areas in which the co-investment into RD&E by cotton growers and the Australian Government has significantly benefited the industry - like our strong improvements in water use efficiency; our efforts to improve environmental performance; our contributions to building the capacity of the industry’s most important resource, its people; and our contribution to the industry’s best management practices program. These are all examples where investment in RD&E has helped to deliver highly valuable outcomes.

The publication also features 25 key industry people who provide their thoughts on CRDC and the contribution of cotton RD&E.

The 40 year anniversary of the construction of the Fairbairn Dam and Emerald Irrigation Scheme prompted the

Central Highlands Cotton Growers & Irrigator's Association (CHCG&IA), alongside motivated growers and industry personnel, to commence

production of a book that will encapsulate the history behind the

development of a resilient and reliable cotton production valley. Captured within these pages, is a history through the words of those involved, with personal recounts from irrigator's - both past and present, industry representatives and those involved with

the construction of the dam. This project provided funding to assist with the research and compilation of the history.

This proposal builds on many years of weeds work supported by CRDC and aims to value add to the earlier work, while providing strategic information to cotton growers in support of MyBMP, based around updating WEEDpak, the Guide to Integrated Weed Management in Cotton.The project aims to develop and expand strategic areas of WEEDpak, providing:• Up-to-date guidelines for Integrated Weed Management in the Roundup Ready Flex system,• Up-to-date information on key weed questions in MyBMP,• More and better information on the potential for damage issues from herbicides used in other parts of the farming system, and• An improved, more user-friendly and more robust weed control threshold for cotton.

The project uses a combination of field and glasshouse experiments, laboratory studies and observations in commercial cotton fields, in collaboration with the weeds work undertaken by researchers at QDPI, Toowoomba.

Work will continue on the weed threshold, with analysis of 8 years of data to re-develop a weed biomass-based threshold, improving on the current density based threshold which doesn’t adequately allow for staggered weed germination. This work will be written up in a series of scientific papers and submitted as a PhD by the Principal Researcher. The work will be supplemented by experiments to validate the weed control threshold using the background weed population, supplemented to ensure strong weed pressure, manipulated with a range of timings and number of applications of glyphosate. An infra-red sensor (GreenSeeker ™) is used to estimate weed biomass.

The weed growth and development information will be validated using a large number of 200 L drums at ACRI, which will be filled with soil and flood irrigated according to normal practices. The drums closely mimic field conditions, but allow individual weeds to be studies without the complications of competition and other field issues. The work will be undertaken as a PhD, supervised through UNE, Armidale, with assistance from the field staff in this project for much of the initial work. The work will complement work by the QDPI team at Toowoomba, who will use at number of large, controlled environment chambers to examine the seasonal requirements for weed emergence, and additional work at ACRI using our 4 germination cabinets. The research will examine 18 weeds which have been identified as being at high risk of developing herbicide resistance (analysis from the QDPI group) and are weeds which are showing up in the Monsanto weed audits as being problematic in Roundup Ready Flex crops. This weed set will be covered in both the QDPI and this project. The project will also cover additional species which are currently in the WEEDpak Weed Growth & Development Guide.

The field experiments will be conducted at the ACRI, Narrabri, with treatments applied at various crop growth stages. Experiments will use detailed crop measurements to assess the post-treatment impact of treatments on cotton plants, monitoring plant height and development, leaf number and area, squares, flowers and bolls throughout the season, and crop yield, fibre quality and time to maturity. The research will expand the Herbicide Damage Guide to cover 29 different herbicides, including information on the identification of herbicide damage and detailed information on the likely consequences of damage on subsequent crop growth and development. Additional detailed work will also be undertaken on 2,4-D damage, and the crop’s response to post-damage management.

Work will continue on the weed threshold, with analysis of 8 years of data to re-develop a weed biomass-based threshold, improving on the current density based threshold which doesn’t adequately allow for staggered weed germination. This work will be written up in a series of scientific papers and submitted as a PhD by the Principal Researcher. The work will be supplemented by experiments to validate the weed control threshold using the background weed population, supplemented to ensure strong weed pressure, manipulated with a range of timings and number of applications of glyphosate. An infra-red sensor (GreenSeeker ™) is used to estimate weed biomass.

The weed growth and development information will be validated using a large number of 200 L drums at ACRI, which will be filled with soil and flood irrigated according to normal practices. The drums closely mimic field conditions, but allow individual weeds to be studies without the complications of competition and other field issues. The work will be undertaken as a PhD, supervised through Dr. Brian Sindel at UNE, Armidale, with assistance from the field staff in this project for much of the initial work. The work will complement work by the QDPI team at Toowoomba, who will use at number of large, controlled environment chambers to examine the seasonal requirements for weed emergence, and additional work at ACRI using our 4 germination cabinets. The research will examine 18 weeds which have been identified as being at high risk of developing herbicide resistance (analysis from the QDPI group) and are weeds which are showing up in the Monsanto weed audits as being problematic in Roundup Ready Flex crops. This weed set will be covered in both the QDPI and this project. The project will also cover additional species which are currently in the WEEDpak Weed Growth & Development Guide.

The field experiments will be conducted at the ACRI, Narrabri, with treatments applied at various crop growth stages. Experiments will use detailed crop measurements to assess the post-treatment impact of treatments on cotton plants, monitoring plant height and development, leaf number and area, squares, flowers and bolls throughout the season, and crop yield, fibre quality and time to maturity. The research will expand the Herbicide Damage Guide to cover 29 different herbicides, including information on the identification of herbicide damage and detailed information on the likely consequences of damage on subsequent crop growth and development. Additional detailed work will also be undertaken on 2,4-D damage, and the crop’s response to post-damage management.

In addition to the research highlighted in this application, the project will allow the researcher to continue his role in advising cotton growers on weed issues, giving expert technical advise to the TIMS Herbicide Tolerant Crop Technical Panel and continuing to review pesticide applications on behalf of NSW DPI for the APVMA that involve the cotton farming system.

Financial performance benchmarking studies have identified increasing fertiliser input costs in the cotton industry. Farm profitability has been eroded as a result of an emerging trend by cotton growers to apply high rates of nitrogen fertiliser. Many growers believe 300+ kgN is required to grow the latest commercially available cotton varieties and achieve potential yields of 14-15 bales per hectare.

Further research is required to validate these claims that high nitrogen (N) fertiliser inputs are necessary to achieve high yields. High N inputs may in fact be the product of poor nitrogen use efficiency (NUE) where a significant proportion of the N applied is either lost through denitrification, volatilisation, run-off or leaching processes, or simply not utilised.

This project will collaborate with other nitrogen related research projects to build a comprehensive understanding of nitrogen loss pathways in cotton farming systems. The research will focus on the impact of various irrigation and nitrogen (N) application strategies on N uptake, nitrogen use efficiency, fibre quality and yield.

Trial results will be shared with collaborating researchers to develop irrigation and nitrogen management recommendations to assist growers optimise N fertiliser applications, improve nitrogen use efficiency, reduce greenhouse gas emissions and improve farm profitability.

This project provides the foundation for greater cotton agronomy research and development capacity within NSW DPI.

NSW DPI is committed to establishing a fully funded permanent position at Narrabri and is currently progressing through the recruitment phase. Dependant upon the experience of the successful research officer the project will focus strongly on professional development and building expertise in cotton agronomy by linking in with existing research projects and establishing collaborative relationships.

This project relates to management of the following programme items for CRDC: Inside Cotton is a complete online historical record library of all information relating to research and industry. representing. Final Report s to date for all Research projects are accessible at www.insidecotton.com. The Primary Industry Health and Safety Partnership(PIHSP) is a collaborative partnership working together under the flag to communicate the National Farm Safe Message. The Aboriginal Employment Scheme(AES) and CRDC have a 12 year partnership for the placement of Year 10 Aboriginal students into a two year work placement programme in an industry position of interest.