The Australian cotton industry has had in place since 1997 a voluntary environmental management system - its Best Management Practice (BMP) Program - that has successfully overcome the limitations of a purely regulatory approach to natural resource management. The BMP Program focuses on the management of pesticides and petrochemicals, soil and water, and native vegetation.

The industry is looking to build on the success of the BMP Program, and is in the process of negotiating for it to provide an alternative means for cotton farmers to comply with any existing or new regulations governing how land and water is managed in Queensland.

Reviews of the BMP Program and of its outcomes highlight that it has led to a decline in pesticides used on cotton farms, a decline in pesticides found in riverine environments, improved stormwater management, improved farm management and a reduction in the regulatory burden on cotton farmers This paper will outline the structure of the cotton industry's BMP Program, highlighting the factors that have been critical to its success, including a detailed discussion on the rationale behind the partnership approach, between the industry and regulators, seen as necessary to achieve inground change. The paper will then touch on the benefits the Australian cotton industry sees in working with the World Wide Fund for Nature (WWF) on its 'Better Cotton initiative.

This project is a long-running one concerned with breeding varieties adapted to Australian conditions, growing practices and markets. During the interval of this particular grant much progress occurred with the development of the original Siokras and Sicala's from a breeding program that began in 1974. The development of Siokra has been widely regarded as a noteworthy achievement since it marks the first time anywhere that an okia leaf variety has been successfully and widely grown commercially. The significance of the okra leaf has been that it has provided some tolerance to Heliothis and considerable tolerance to mites. Titls pest tolerance has resulted, where keen attention has been paid to pest management, in the savings of two or even more sprays. Very importantly both Siokra and Sicala had genes for bacterial blight resistance incorporated and had ready marketable fibre. These properties led to their readily acceptance by cotton farmers and they soon comprised between 65-75% of total Australian cotton plantings.

This talk is heavily dependant on slides, so the following 1s really only a &quote;background&quote; paper. My approach when giving such a talk to canegrowers, has been to devote the first half to explaining why it is essential that an industry be seen to be environmentally sensitive. If you, the grower ( be it cane or cotton ) don't appreciate that need, you are not likely to listen with any degree of interest. I've heard Maree McCaskill, Executive Director of the Australian Cotton Foundation speak at a Canegrowers' conference, and imagine many of you are already aware of the public relations benefits of such an approach.

Southern Valley irrigators recently sought funding to assist with an education and outreach program to assist with two issues which had been identified in their region. The two issues chosen to tackle were:

1. Spray drift – this is a very topical issue throughout the cotton growing regions and therefore thought it would be beneficial to continue the education process throughout the southern valleys.

2. Irrigation – Water as the most precious resource, and labour one of the most expensive inputs into production systems was considered to of great benefit for growers. The plan was to expose growers to a range of irrigation management plans and farm setups in an aim to showcase efficiency gains that could be made within their own businesses.

A series of workshops were co-ordinated to educate growers and industry about spray drift. These workshops were rolled out in Deniliquin, Griffith, Barellan and Lake Cargelligo. A total of 183 participants attended.

In collaboration with IREC, a bus trip to Queensland was arranged. The tour north was an opportunity for people both from the cotton industry, as well as other irrigated enterprises to go and look at other farming operations. This allows growers to take ideas that may be applicable to their situations at home to help improve their production systems and ensure tlong term sustainability and profitability.

This project, led by the Tasmanian Institute of Agriculture focused on the use of data and

autonomous technology in helping farmers make informed decisions and improve their

irrigation efficiency on pastures. The project collected data on water and energy usage as well as

pasture production from five commercial pivot irrigated sites across the North and Northwest of

Tasmania over three irrigation seasons from 2015 to 2018. Using the data, the project team

worked with the farmers involved to make changes improving water use efficiency and

monitored each site to measure the success of these changes.

The major objective of the project was to identify key irrigation system modifications and

practices that could be efficiently and effectively adopted by dairy farmers in achieving

improvements in energy and water usage and increasing pasture production per ML of irrigation

applied. A second objective was the development and testing of an autonomous sensor based

pressurised irrigation scheduling system that could improve energy, water and labour inputs.

Each pivot’s area was mapped to determine variability in soil types and elevation. Soil samples

obtained provided the soils’ water holding capacity and other details of major soil properties.

Weekly pasture growth rates were collected from each of the sites during each irrigation season

using a rising plate meter. As part of the programs management there was no interaction with

the farmer’s during the first irrigation season (2015/16). At the end of the first season,

workshops were held with all participants to discuss what had been found with the energy and

water use and pasture production, on each farm and to provide feedback on possible methods of

improving the management of each irrigation system. During the 2016/17 irrigation season, a

weekly update of rainfall and evapotranspiration for each site was provided to the participating

farmers along with free access to soil moisture and temperature data that could assist with each

properties irrigation scheduling.

In addition to providing weekly rainfall and evaporation data in the 2017/18 season, weekly

discussions were held with each farmer to assist them with their irrigation scheduling decisions.

On one of the five commercial sites, cameras were installed to assess the ability of cameras to

measure pasture growth rates autonomously, and assist the development of the autonomous

irrigation control platform (VARIwise). The camera technology was tested in the 2016/17

season and the VARIwise control platform tested during the 2017/18 season and compared to

both flat rate and variable rate water applications based on VRI prescription maps developed

from electromagnetic conductivity (EM38) and elevation data from the site.

Field days and workshops were held across Tasmania as well as in Victoria, Western Australia,

South Australia and New South Wales, during the three year project. A series of presentations

were developed for use at field days, workshops and online webinars. A factsheet was

developed on Variable Rate irrigation and a number of short videos were developed and

uploaded to YouTube for extension and training purposes. There were also a large number of

media interactions including radio and TV presentations and publication of project outcomes in

newspaper and magazine articles, both in Tasmania and nationally.

The Australian cotton industry has been practising curative conventional insecticide resistance management for thirteen years now. initially it was targeted at pyrethroid and endosulfan resistance management in Helicoverpa armiger&quote; but more recently has also included other conventional insecticide groups (such as the organophosphates and carbamates) and acaricides for control of Tetranychus urticae. In addition, the imminent commercialisation of transgenic cotton expressing the CrylAc insecticidal crystal protein from Bacillus thuringiensis, has necessitated the introduction of a preventative Resistance Management Strategy. This paper aims to give a brief history of the Australian conventional Insecticide Resistance Management (IRM) Strategy and an outline of the proposed Resistance Management Strategy for Bt transgenic cotton.

Following the establishment phase of the Smarter Irrigation for Profit project, a Rural R&D for Profit initiative, participants identified that one of the key barriers to farmers using scheduling tools is the diversity of tools available, each with its own strengths and weaknesses, they expressed a need for a simple resource that could assist farmers and extension officers in the selection of an appropriate irrigation scheduling tool or tools for their needs. This project aimed to provide a summary of a range of irrigation scheduling tools that have been reviewed, tested or utilised by Smarter Irrigation for Profit participants.

Experience on the ground also found that if scheduling tools are to be adopted by industry, they need to be simple — simple to install, setup, use, interpret and respond to. Many of the tools tested required significant effort to learn how to use appropriately so as to achieve any potential benefit. Providing a simple way to compare and consider a range of tools to enable the selection of a suitable tool was proposed as the basis for this document.

It is envisaged that this resource will provide a starting point for others who need to review tools prior to implementing them on farm. This project is not endorsing any particular product. Any appropriate tool will need to be considered for the circumstances in which it is to be used.

Irrigation Scheduling

Crops that are kept within acceptable stress limits during their growth cycle have the potential to produce optimum yields of high quality. The aim of irrigation scheduling is to keep soil moisture within a desired range, usually between field capacity (full point) and a predetermined refill point for optimal growth.

The irrigation management decision-making process involves deciding “how much” to irrigate, at “what position” in the field, and “when” to irrigate by considering:

* the current water content of the soil

* the current rate of crop water use.

* the soil’s readily available water-holding (RAW) capacity and refill point

* the application rate (millimetres per hour) of the irrigation system. This allows the calculation of how many hours are needed to apply the required amount of water (in millimetres).

* the evenness of water application (uniformity) and efficiency of the irrigation equipment in your field

Irrigation scheduling tools seek to assist farmers to make informed decisions with either the current water content of the soil, the rate of crop water use, or both.

As a result the range of scheduling tools can be grouped into those that monitor the soil water content, those that use weather data to estimate how much water the plant has been consuming, and those that monitor the plant for water stress.Experience has shown that using multiple methods to assess the amount and timing of irrigations can improve scheduling decisions. The ability to manage and interpret data has improved considerably, and some scheduling tools are now combining a range of soil and plant data into one software platform in order to improve the ease the process of making irrigation scheduling.

This project provides a summary of tools used by participants in the Smarter Irrigation for Profit project grouped on the basis of measuring:

* soil water content

* weather based crop water use

* plant stress

* combinations of those above

Combination tools include the growing number of software delivery platforms that can connect to a range of different sensors and deliver data to web connected devices for growers and advisors.

This review has not sought to be comprehensive and cover every available tool, but instead focusses on those that have been used by participants in the Smarter Irrigation for Profit project. The following details the list of tools that have been included in this document. The project is not endorsing any particular product. Any appropriate tool will need to be considered for your own circumstances.

This funding supported the tour of a number of southern irrigators as part of the Maximising On-Farm Irrigation Profitability project, a sub-project under the Smarter Irrigation for Profit project. A group of irrigators from southern NSW and northern Victoria travelled to the Gwydir Valley to attend the Gwydir Valley Irrigators Association annual research field day as well as visit other irrigation properties and the ACRI/CSIRO Research site. The impact of the tour was immediate, both providing networking opportunities for growers of the north and south and providing exposure to new precision irrigation systems technology.

Cotton production in Australia is limited by the lack of water availability in most years. This project aimed to enable growers to adapt and tailor their irrigations to an uncertain future climate and water availability situations based on definitive data to manage risk. Earlier research supported by the CRDC enabled developing an irrigation scheduling method for furrow irrigated cotton based on canopy temperature monitoring. Through being strongly related to soil water availability, canopy temperature measurements enable continuous monitoring of a crop’s requirement for irrigation using a plant-based method that is practical to use on commercial farms. Through this project the canopy temperature method was further refined for fully irrigated systems and its use tested in partially irrigation situations. The three key areas of research for this project were:

1. Integrated Irrigation Agronomy for High Yielding Systems:

To achieve the highest yields the irrigation management of the crop needs optimizing through the entire crop development period. We conducted detailed research trials at the Australian Cotton Research Institute (ACRI) near Wee Waa (NSW) to optimize irrigation strategies at planting and during early, mid and late season which are explained below:

We conducted a comparative investigation of pre-watering and watering up at the ACRI to determine the best irrigation strategies for crop establishment. Watering up one day after planting resulted in slower germination and 25% less plants established compared with the crop pre-irrigated a week before planting. Soil temperature in the watered up treatment was up to 2.4 °C cooler than in pre-watered soil which most likely affected germination and establishment. These results are important in that there was only one cold shock (i.e. minimum air temperature <12 °C) during this trial in 2015-16 season compared with 20 and 10 cold shocks in the following two years, respectively, yet plant establishment was affected. It is important to consider these effects of watering up in cotton and, where watering up is unavoidable because of other farm factors, planting time may be adjusted to avoid cooler soil temperatures.

The timing of first in-season irrigation (excluding at planting) drives the establishment of a plant with sufficient vegetative growth to support high yields. Bollgard® varieties with high fruit retention may benefit from vigorous plant growth translating into high yields. A trial conducted at ACRI during 2015-16 to optimize the timing of first irrigation did not generate the expected treatment differences in plant development and yield because of wet weather conditions. It was identified that thermal cameras can be an effective tool for monitoring plant water stress during early season when canopy temperature infrared sensors cannot be used because of smaller canopy.

Timely application of mid-season irrigations is most important in terms of its effect on yield. In practical situations most cotton farmers may have to make an irrigation decision few days in advance. We investigated integrating canopy temperature and short-term weather forecast to make an irrigation decision five days in advance. Irrigations were planned in advance by either using an average daily stress time value based on historic data (treatment 1), or applied earlier or later than the predicted date based on short term weather forecast using dynamic deficit approach (treatment 2). Both the treatments underestimated the canopy temperature stress time compared with the measured observations. It was concluded that an irrigation decision

made in advance should be based on canopy temperature that is predicted from short term weather forecast rather than historical climate data.

Detailed trials were conducted at the ACRI to optimize the timing of last irrigation using canopy temperature sensors in a fully irrigated cotton system. The results showed canopy temperature sensors can be used for scheduling last irrigation with a need for further testing in different weather conditions to build confidence in the results.

2. Irrigation scheduling with limited water

We conducted detailed trials to develop irrigation decision frameworks in limited water situations to limit the risk and seasonal variability. The utility of canopy temperature sensors was investigated in partially irrigated systems with three different row configurations commonly used in cotton industry. There were strong relationships between yield and canopy temperature (and its derivatives) in all row configurations. As canopy temperature is affected by a plant’s access to (or lack of) soil water, regardless of location of water within soil profile, this method may help improve irrigation scheduling in partially irrigated systems where different row configurations are used. We tested applying a single irrigation during flowering at canopy temperature stress thresholds higher than that used in fully irrigated systems. In the years we conducted these studies we could extend/delay our irrigations with little impact on yield and yield gains in one instance. Further research will be needed to understand how we can best utilize our ability to better quantify stress (using canopy temperature sensors) in years that are dissimilar to those experienced in this study to manage risk in limited water situations.

3. Research Support for high impact delivery and adoption

Research support was provided in collaboration with the Cottoninfo team through on-farm trials and field days. On-farm trials were conducted in different cotton growing valleys in New South Wales (Wee Waa, Rowena, Walgett) and Queensland (Emerald, St. George), where farmers integrated the canopy temperature approach in their irrigation decision making. The overarching philosophy of these trials was to provide farmers the opportunity to integrate different tools for making an irrigation decision. Trials in Emerald and St. George resulted in saving at least one irrigation on both farms using canopy temperature sensors without impacting yield. This research enabled farmers to use an irrigation scheduling tool that is based on real-time monitoring of a crop’s need for water. A commercial partner has been identified to extend canopy temperature approach of irrigation scheduling to the Australian cotton industry.

Some important future research areas are: 1) Utility of plant-based method of irrigating such as canopy temperature for optimizing crop water use efficiency from the perspective of less water use; 2) capturing spatial variability on large farms with canopy temperature sensors, and/or how many canopy sensors per farm are required to make the best irrigation decisions? 3) Continuing research on utility of canopy temperature sensors in partially irrigated systems, and 4) Utility of thermal images in assessing crop stress during early cotton season.

This project was funded by the Department of Agriculture and Water Resources, and the Cotton Research and Development Corporation through Rural R & D for Profit program.

Grower-led irrigation system comparison in the Gwydir Valley aims to collect commercially relevant comparative data on different irrigation systems. There were two parts to this project, an irrigation system comparison and an implications for capital investment, management and the resource requirements (water, energy and labour) associated with different cotton irrigation systems and new technologies. Incorporated into this is the adoption of automation technology and different approaches to farming systems.