Soil compaction in the cotton industry has been identified as a major limitation to crop growth. This led to the establishment of several CRDC funded research projects dealing with the management of soil compaction. However, it has proved difficult to diagnose this problem in the field. In mid-1987 the Macquarie Valley Soil Management Service was set up to aid growers with their soil management decisions; they found that in about 30% of cases, it was difficult to make recommendations about the degree of soil compaction. A majority of this uncertainty was due to poorly defined techniques for assessing soil condition. The aim of this project was to evaluate, and where necessary refine, the techniques currently available for soil structural assessment in the field. The techniques for the assessment package, where possible, have to be rapid and repeatable, with low degrees of operator subjectivity. They will help farm agronomists, consultants and extension personnel to make better soil management decisions, and monitor the changes in structural condition from year to year. The package will be incorporated into the SOLpak manual.

The purpose of this CRC funded project was to provide scientific assistance to the Queensland Cotton (QC) commercial trial program in the Burdekin region.

To achieve a greater understanding of the regulation of cotton fibre differentiation, more fundamental information is needed on the signals and mechanisms associated with fibre initiation. The extensive genetic knowledge of Arabidopsis leaf trichomes could aid in the elucidation of the genetic mechanisms controlling cotton fibre differentiation. Trichomes are small hairs on the plant surface, originating from single epidermal cells in a developmental process that appears very similar to that of cotton fibres. Arabidopsis trichome development has been extensively investigated, and several genes that control the process have been characterised. One gene essential for trichome initiation is TRANSPARENT TESTA GLABRA1 (TTG1), and loss-of-function mutations in TTG1 result in an almost complete absence of leaf trichomes. TTG1 plays additional roles in numerous pathways in Arabidopsis, including root hair initiation, anthocyanin production and seed coat mucilage production. In order to isolate genes required for fibre initiation in cotton, functional homologues of Arabidopsis TTG1 in cotton have been sought.

Four putative homologues of Arabidopsis TTG1 have previously been isolated in this laboratory by RT-PCR of mRNA prepared from cotton fibres, and are termed GhTTG1-4. Sequence comparisons between the four cotton deduced proteins and Arabidopsis TTG1 showed that they form two groups, with GhTTG1 and GhTTG3 being closely related to each other (87% identical and 93% similar) and to TTG1 (79% and 80% amino acid identity respectively). GhTTG2 and GhTTG4 formed the second group, with 95% amino acid identity to each other and lower (approximately 62%) identity to TTG1. An analysis of the genomic originis of the GhTTG genes demonstrated that each is derived from the same ancestral diploid genome.

The availability of accurate and continuous weather and climate data is essential for strategic research, operation of decision support systems (eg. CottonLOGIC, OZCOT crop simulation model) and numerous operational aspects of cotton agronomy and management. In addition historical climate data is being used by researchers to assess the potential of cotton growth in new regions and to analyse the performance of crops in current seasons in the context of the whole climatic record. Increasingly consultants and growers are using this information for making informed management decisions.

At the start of this project the industry supports the maintenance of 14 stations spread throughout the cotton growing regions. These stations require regular maintenance and annual calibration. The information collected from these stations is made available via the Cotton CRC’s web site. After numerous problems installing the network they were operating at an acceptable level. However, the stations are now over 9 years and components are failing more frequently and the stations show visible signs of degradation from the weather.

A brief outline of the major results and outcomes form this project is given below.

1. Provision of weather information through the existing cotton industry weather station network.

These weather stations are now over nine years old. Of the initial 14 only five remain functioning. The parts from the stations removed from the field are being used to maintain these functioning stations. Three are being used for experiments while two remain in the field (Merah North and Breeza). More reliable and continuos data is now available through the SILO Internet site.

During this time as part of this project we also installed a new weather station at ACRI.

2. Provision of historical climate patched point data sets to the Australian Cotton Research Institute for research purposes.

ACRI and Cotton CRC researchers now have reliable and easy access to up to date weather information and historical data for research purposes. Researchers access this data through an internal website from a data server located at ACRI. On a daily basis the SILO web services updates the server with the latest numerical weather measurements recoded. This service has enabled any project utilising this data to run more effectively. No longer is there a significant cost in time and dollars to obtain this data.

3. Collaboration with partners of the SILO project to develop weather and climate tools specific to the cotton industry.

In gaining reliable and easy access to continuous climate datasets has enable a number initiatives where tools for research and decision support to be developed in collaboration with the SILO team. Currently all tools developed are available free to members of the Australian cotton industry. The tools developed and initiatives undertaken during this project are as follows:

SILO/Cotton CRC day degree calculator - allows user to enter a starting date and finishing date to calculate the day degrees.

SILO/Cotton CRC day degree target calculator - This decision tool is similar to the day degree calculator described above only that it differs in enabling the users to specify a target day degree.

Early season diagnosis tool - The early season diagnosis (ESD) tool was developed for the Cotton CRC’s website to assist with the agronomic management of cotton crops. The ESD has been linked to the SILO day degree calculator, and allows the users to enter the sowing date and the dates on which the measurements were taken.

HydroLOGIC - Fundamental to the effective use of the HydroLOGIC software released to the cotton industry in September 2003 is gaining access to daily weather data. The SILO initiative was able to contribute to the development of HydroLOGIC by providing access to Historical patched point datasets for major cotton growing regions and developing computing routines were developed to enable HydroLOGIC to directly access SILO’s patched point datasets from the Internet.

Final report- IPM in Bollgard II: coping with changes in pests and climate

The cotton boll contains the seeds of the plant to which long, white fibres are attached. The cotton industry takes advantage of these fibres to spin yarns for textile production. A major challenge facing the cotton industry is that of crop loss to insect attack. The primary insect pests of cotton preferentially attack the boll, causing damage to the commercially important fibres. The recent introduction of Bt-transgenic varieties, containing genes with anti-pest properties from the soil bacterium Bacillus thuringiensis, has had positive impacts on pest control and pesticide usage. These transgenes are under control of constitutive promoters, resulting in endotoxin expression in all parts of the plant. This constant high level transgene expression may have several detrimental effects, such as placing strong selective pressure on pest populations to develop resistance, non-target effects of the transgene on other organisms, a yield penalty to the plant, and the presence of transgenic protein in secondary commercial products. For these reasons, this project aims to identify promoters that could be used for tissue-specific expression of anti-pest molecules in only the boll wall of the plant. A differential screening approach was used to identify several boll wall-specific mRNAs and the temporal and spatial abundance of these transcripts was determined using Northern analysis. The promoters corresponding to these transcripts were identified using Genome Walker® PCR and isolated from genomic DNA by PCR. Transient transformation of various cotton tissues with these promoters driving reporter expression resulted in predominant boll wall expression. The cotton promoters identified here provide an alternative tool to constitutive promoters for use in future transgenic varieties.

SIRATAC is an on-line computer-based pest management system for irrigated cotton. It makes recommendations for insect control on the basis of samples collected from individual management units. Daring the 1980s, the SIRATAC methodology was marketed through SIRATAC Ltd. A reimplementation of SIRATAC was initiated in 1986 (SIRATACPlus). However, by 1988, it had become clear that on-line management systems were an evolutionary dead end. SIRATAC Ltd went into liquidation in mid-1989. The SIRATAC Plus project was abandoned in early 1990. During the 1989/90 and 1990/91 cotton seasons, SIRATAC was operated by a newly-formed User Group (SUG). The collapse of the SIRATAC framework coincided with the initiation of Project CS51L, Economic optimisation in SIRATAC. The abandonment of the SIR ATAC framework also coincided with increasing doubt concerning the ability of cotton to compensate for early insect damage. This circumscribed the usefulness of the SIRATAC crop model for formal optimisation. Thus, during the course of the project, the emphasis shifted from mathematical optimisation using validated simulation models towards the development of a novel approach to decision support as a replacement for SIRATAC.

This project has part funded maintenance of HVI900 and FMT3 cotton fibre testing instruments in CSIRO’s fibre testing laboratory at ACRI for the 2005/06 season. The laboratory supports measurements of fibre quality from cotton experiments in CSIRO’s breeding program and research projects by other organisations and projects.

More than 20,000 samples were tested by HVI and 10,000 samples by FMT.

Global cotton production and market dynamics indicate Australia needs a future edge with fibre quality to ensure buyers will want our cotton in preference to our competitors. This means developing varieties, management and processing to ensure we deliver better fibre. There may be opportunities for premium fibre products in future. Thus the CSIRO cotton breeding program raised the emphasis on developing improved fibre varieties to address these needs.

Negative associations between yield and fibre quality present challenges for variety development. We have accurately measured these associations and developed breeding population sizes to ensure the rare combinations of high yield and quality can be identified. Accurate measurement of fibre quality is an important component of that work.

A number of new breeding lines have been developed to address the objective of improved fibre quality and at high yield levels. In addition there are lines with excellent fibre properties to potentially target speciality (premium) markets. These lines are under further evaluation and are also used in developing speciality Bollgard®II varieties. Sicala 350B, released in 2005, has very long fibre and is attracting interest in the market. We have identifies possible superior lines of this type.

The VIII International Colloquium on Invertebrate Pathology and Microbial Control and the

VIth International Bacillus thuringiensis Conference were held at Iguassu Falls, Brazil,

August 18-23,2002.

Of the 347 registrants at the Colloquium, >l00 were from Latin America, primarily from

Brazil and Mexico. There was an unusually strong contingent from the UK, indicative of an upswing in there. The only Australian registrants were

Dudley Pinnock (Microbial Products, Adelaide), Cheryl Beard (CSIRO Entomology) and me.

The Colloquium had the usual full program of symposia, contributed paper, poster sessions

and workshops, including one on Ethics, Legal and Regulatory Concerns of Transgenic

Plants. The plenary session was devoted to baculoviruses, presumably because of the interest

of the Chairman of the Organising Committee because there appeared to be no new

developments flagged in any of the four presentations. As there were three concurrent

sessions, my attention was given largely to the bacterial presentations. The highlights of the

conference were the report of resistance to Bt in a natural populations of a second species, the

large interaction between plant variety and Bt toxins, and the absence of non-target effects of

Bt.

I presented two contributed papers and chaired a Contributed Papers session. At the Business

Meeting during the conference, I took over the role as secretary of the Society for

Invertebrate Pathology, having previously been elected by postal ballot.

The Leaf Chamber Fluorometer is an exciting new addtion to the physiological instrumentation available to the scientists at ACRI. The LCF has raised the investigative capabilities of the cotton research team and made it possible to study in greater depth stress related physiological responses in cotton. Its application will be broad encompassing stresses induced by pests and environmental extremes such as temperature and available water. Current and future projects will be measuring gas exchange and chlorophyll fluorescence concurrently, exploring and revealing the physiological origins of stresses in cotton that could result in declining yield and fibre quality. Significant findings using the LCF are expected over the next few years which will maintain research of an innovative standard in areas of cotton physiology for the team at ACRI.