Increasing pressure from industry and environmental sectors has begun to force the

Australian cotton industry to rethink its approach to chemical application. This has

led to an increase in ground-based applicators this current year to a record number.

While this is a positive step, it in effect deregulates the industry, moving from a

highly accurate controlled rate applicative technique by a small number of highly

trained operators to a large number of relatively unskilled applicators. As a result the

application of a given chemical in a field and growing area may vary widely with little or no control.

Ground based application of insecticides does allow for banding of costly or limited products, timely application when conditions are more conducive to maximum efficacy, and for optimum target efficiencies. New spraying units offer wide booms, high load capacity, high clearance, air assist nozzles, four wheel drive and speed that combined are able to compete with aerial based application.This project was designed to consider the issues involved in the spraying task and aimed to coordinate efforts with other researchers to achieve the following:

I) Benchmarking of current operational parameters of ground based spray application equipment and techniques. This included the recognition of grower questions and concerns regarding their current practice.

2) Summarising the results from the survey and define the areas of concern that can

be readily addressed. These may include but are riot limited to the effect of speed

on application, use of shields, end of row problems, and nozzle configuration (angle

of incidence, number, position). This will be done in the wind tunnel (if practical) and the field.

3) Develop documentation of project outcomes and report back to the industry. This will include testing protocols, a listing of datum settings for ground based application rigs and recommendations of changes with increasing bush size.

The research had three parts: * Quantify the V AM fungi at depth in the soil * Determine the rate of colonisation of roots of cotton by V AM fungi. and * Develop understanding of the relationship between rate of colonisation and quantity of V AM fungi

Drip irrigation has been advocated as one way of improving both yield and water use efficiency for irrigated cotton. It has even been claimed that drip irrigation can be used to 'crop areas previously considered unsuitable for conventional irrigation methods .... because. ... 'the root zone is maintained at both optimal water and nutrient levels' (Anon,

1988). In this context drip irrigation may be considered a 'non independent' irrigation system where the uniformity of application of water and nutrients by the irrigation system overcomes viability in soil properties. Irrigators have been led to believe that the precision of application of water to the crop from drip irrigation will enable soil and climatic limitations to be to be adequately managed. Field experiment on cotton comparing irrigation treatments were conducted at Warren in the 1999/2000 and 2000/2001 seasons. The control was irrigated at 100% of predicted crop water use (ETcrop), and three treatments that applied 50%, 75% and 125% ETCrop .

Cotton yield was greatest in the 100% treatment followed by the 75% and 125% treatments with lowest yield coming from the 50% treatment for 1999/2000 season. In contrast the 100% and 125% were similar followed by the 75% and 50% for the 2000/2001season. This yield trend, combined with similar soil moisture contents in both the 100% and 125% treatments, suggests that the 100% treatment was supplying adequate water to satisfy crop demand for the 1999/2000 season. Some waterstress was observed in the mid season in 2000/2001 season because of small amounts of underirrigation (0.5 mm Iday).

We found that the irrigation efficiency was limited in both seasons by the large amount of water required to germinate the crop (27% of water applied to the 100% treatment). It is clear that it would be better to use this extra irrigation water to obtain the greater production recorded between the 50% and 100% treatments than to use it only for crop establishment.

We found that gradual development of waterstress (by under-irrigating daily) allowed cotton plants to make osmotic adjustments that allowed the 50% treatment to yield only 17% less than the 100% treatment despite only receiving 31% less water.

Neutron probe readings showed that treatments receiving insufficient water to satisfy crop demand were able to extract water from part of the soilprofile that was not wet by irrigation. Use of this water allowed the 50% and 75% treatments to grow at similar rates to the 100% and 125% treatments for one month in peak growing conditions after the soil was saturated by rain in late December(1999/2000 season) while rain in November of the 2000/2001 season had a similar effect.

Neutron probe readings proved to be sensitive to small changes in applied water and hence are a useful scheduling tool for drip irrigated cotton.

Hands-on training in soil management was given to one hundred & seventy members of the Australian cotton industry at a series of 11 courses between October 1997 and

September 1999. The courses were held in the Narrabri, Warren, Moree, Emerald, Dalby, Wee Waa, Goondiwindi, Gunnedah, Theodore, Walgett and Bourke districts.

The main aim of the courses was to demonstrate how to use 'SOILpak/by Cotton Growers, ThirdEdition ' *, with emphasis on soil sampling for yield map interpretation. Soil monitoring for farm accreditation schemes were also discussed. Most of the soil

inspections were carried out via 1.5 metre deep backhoe pits, which usually were dug in triplicate.

In early season growth disorder, or 'bacterial stunt', bacteria infect the roots of cotton and inhibit plant growth and VAM development. The disease is most severe on heavy clay soils that are often high in nutrients. The fine roots of seedlings turn brown (not black) when infected. Bacterial stunt was detected in 17 of 43 fields examined. Maturity was often delayed and yield losses were occasionally as high as 50 %. A low level of bacterial stunt appears to be widespread. The pathogenic bacterium can be isolated using simple laboratory media and collaborators at the University of QLD have used DNA fingerprinting to confirm its identity. None of the currently available varieties have resistance to the bacterial stunt pathogen and there is little potential for controlling bacterial stunt by chemical means. Large increases in early growth and boll production were obtained in fields with bacterial stunt by maintaining moisture in the topsoil, using mulches and supplementary irrigation. This enabled proliferation of cotton roots in the most fertile part of the soil. Apart from selecting cultivars with good agronomic characteristics, manipulation of soil water content and maintenance of good soil structure using cover-crop mulches and modified irrigation are the best options for improving early season growth of cotton affected by bacterial stunt. It is anticipated that if cotton crops with a mulch cover are managed to prevent early cut out, then the increases in early season growth observed in this project can be converted to yield increases

Aims : To utilise the Cotton Research Unit (CRU) and the Agricultural Production Systems Research Unit (APSRU) modelling capabilities to identify where and how cotton management can be improved and to deliver these outcomes to the cotton industry. Specific objectives will be to: . * to utilise the total modelling capacity of CRU (CERCOT) and APSRU (APSIM) to undertake a risk analysis study, for each cotton region, to provide information for better agronomic management, especially addressing the issues of soil fertility, nitrogen application, sowing date effects, use of limited irrigation water, varietal selection and row configuration *. to demonstrate the value of linking crop and soil monitoring with the predictive capability of a cropping systems model (APSIM) to make better decisions regarding planting options (crops), timing and fertiliser input requirements * to assist with development and validation of stable parameters to quantify differences between cotton varieties and incorporate these into CERCOT, to allow the model to accurately reflect varietal differences in performance and enhance the value of predictions * to involve industry in developing and implementing mechanisms for delivery of simulation outcomes and to provide access to information from this project for evaluation.

Field experiments at Narrabri in 1993, 1994 and 1995 have utilised overhead sprinklers and, portable rain-out shelters. Results have indicated that microbial damage is initiated and, develops when mature exposed lint is subject to wet weather in the field prior to harvest., Microbial deterioration of cotton fibre continued within the module when the module moisture, was high. Techniques have been developed to apply anti-microbial substances to seed cotton, prior to producing modules and to generate different moisture contents in "mini'' modules for, storage experiments

Aims: 1. Identify the most appropriate cotton plant types or varieties for dry season production in NW Australia based on characteristics of yield, quality and maturity 2. Investigate the effects of specific agronomic/ physiological factors on cotton growth and performance in the dry season and integrate those factors into a robust agronomic package tailored to the most appropriate varieties 3. Develop and evaluate pest management systems with minimal inputs of pesticide, maximal use of natural mortality factors based on transgenic cottons expressing Bt genes for management of Lepidopteran pests. 4. Integrate appropriate varieties , agronomy and pest management to provide a technological package for the establishment of an irrigated dry season cotton production system in NW Australia.

Water use efficiency is a key measure of an irrigation system and its management. Benefits from highly efficient irrigation systems include: greater whole farm water security, lower operating costs, improved production per megalitre of irrigation water supplied, maximised production during dry years, and improvements in environmental management both on-farm and within the broader catchment. In the context of the Australian cotton industry, increases in water use efficiency can be achieved through limiting irrigation losses within the system of conveyance, storage, distrlbution and field application of irrigation water.

As competing demands for water resources grow, so to does the need to find solutions for better and more efficient water use and irrigation practices to meet farm, industry, domestic and whole catchment requirements. Only recently has the environment been recognised as a user of water resulting in concerns regarding existing irrigation water allocations. The cotton industry in Australia is seen as a large user of water and consequently is one industry facing pressure due to competing demands for water. Some 80% of cotton grown in Australia is irrigated. Security of irrigation supply determines the level of production and hence the industry has a major interest in the efficient management of the water resource. Improvements in on-farm water use efficiency have been identified by government, industry, community and water providers as part of a solution to the competing demand for the limited water resource. In the past there has been debate about the level of efficiency of the cotton industry with regards to its water use practices. Most arguments have traditionally been based on perception rather than fact. Hence, there is a need for a system of benchmarking on-farm irrigation efficiencies in the Australian cotton industry, and to better evaluate irrigation design, management and practice options that assist in improving industry benchmarks.

Online content is now a major resource for many in the agricultural community, with downloadable publications, interactive apps, and multimedia platform providers such as YouTube increasingly being utilised by government and businesses to extend detailed messages to clients.The primary objective of the project was to build on the repository of easily accessible short multimedia (video) files created in DAQ1302 that communicate scientifically-based crop production, crop protection and best practice principles to a diverse audience. Over the past decade, information extension has moved from being predominantly hard copy publications and face-to-face presentations to an eclectic mix of material, both print and multimedia.

Industry support for both video projects has been excellent, with 70 individuals from 25 different organisations, as well as growers participating as presenters or content contributors. There have also been many conference delegates or field day attendees who have provided short comments that were utilised in some of the videos.

Between July 2016 and June 2018, this project had produced 43 videos for public viewing on the YouTube Channel, plus several more for promotional purposes relating to cotton conferences.

The project’s focus is to expand the searchable archive of production and industry-related topics currently available on the CottonInfo YouTube channel (youtube.com/cottoninfoaust). As at 30 June 2018, the channel had received a total of 760,623 views, with a total estimated watch time of 769,647 minutes (equivalent to 76.35 weeks).

The project team had also assisted with videos for other groups or individuals, with services from editing and production, to branding and closed captions. he cotton industry already has a considerable investment in many information products such as the cotton production guidelines and infoPAKS, and videos add value to this repository by utilising vision and audio to communicate and extend ideas and concepts in an informative and entertaining way.

The cotton industry’s joint extension program, CottonInfo, is designed to service the commercially unmet cotton research and development information needs of growers and to support industry efforts to improve practices, productivity, competitiveness and environmental performance. The videos produced in this project are CottonInfo-branded, supporting the CottonInfo strategic goal of making R&D information, trusted advice and specialist technical R&D knowledge readily available through a variety of different communication channels.