Neps are clusters of fibres or entanglements of fibres. They are classified as biological neps, mechanical neps and white specks. Biological neps are those that contain foreign material; mechanical neps contain only fibres and are the result of mechanical manipulation during processing; and white specks are neps that are found as light or white spots on fabric due to their resistance to dyeing. Upwards of 90 % of visible neps in the dyed fabric contain immature fibre and appear as white specks. It had been estimated that the United States alone has lost as much as two hundred million dollars annually due to these dye defects. To develop predictions of white specks, large field-to-fabric studies have been undertaken jointly by the U. S. and Australia. A new image analysis system has been developed and provides quick and accurate measurements of the problem. Now, high-speed fibre measurements can be related to the fabric white speck level. Micronaire, detects extreme cases of white specks, but is more useful when the mature level of micronaire is known for an individual variety. AFIS also shows promise in detecting white speck potential Equations using micronaire and AFIS data are being developed to predict white speck. Meanwhile, variety, micronaire and level of cleaning should be tracked for all ginned cottons along with quality data from the end buyer or at least records of bales which industry has questioned as problematic for neps. This historical data will yield databases which will let the producer/ginner know what micronaire ranges are acceptable for their varieties. The information can be then be used to estimate whether or not a particular cotton is more prone to neps.

The Cotton Pest Management Guide 2013-14 is the industry’s premium resource for insect, mite and weed control, disease prevention, biosecurity and spray application information. The Guide builds on the wealth of knowledge from research the cotton industry has undertaken since the publication first began in the 1980s and is an important tool for growers, agronomists and consultants alike. Importantly, when it comes to protecting the crop, growers are not alone - insects, weeds and diseases do not respect farm boundaries, so it’s important that the industry works together to manage pests.

The Cotton Pest Management Guide is published by the industry’s joint CottonInfo team and is updated each year to incorporate consistent improvements in industry best practice.

Cotton growers generally recognise crop performance or yield as the best indicator of soil biology. The record yields of recent seasons indicate that farmers are generally looking after their soils well from the perspective of plant nutition and control of soil bourne diseases. However, there are a number of concerns which may impinge on the continued success of cotton crop performance. These include questions such as:

1)Are current cotton growing practises sustainable in the long term?

2)Will declining soil carbon levels present problems in the future?

3)Is the quality/biology of cotton soils under threat?

4)Are there better ways of looking after our soils?

Crop yield can be primarily driven by a combination of factors associated with soil chemical and physical fertility and best practises in crop selection and management. However, for a more complete integration of all components of soil biology into decision-making tools used by farmers, there is increasing recognition of the contribution of soil biological processes to 'healthy' soil.

Weeds are a significant threat to all farming systems in NSW. Glyphosate tolerant cotton has been rapidly adopted by the Australian cotton industry since its introduction 18 years ago and currently accounts for about 99% of all cotton crops sown. This has led to a change in weed management practices with growers moving away from applying residual herbicides in anticipation of a weed problem, to dealing with known weed issues in fields using predominantly glyphosate to control surviving weeds.

These changes have resulted in a shift in the weed species found across cotton growing regions. Increasingly the broadleaf weeds: flax-leaf fleabane and sow thistle, dominate weed spectrums in cotton crops, and with increasing weed burdens in the non-cotton component of the rotation. Other important weeds include: the emerging threat of awnless barnyard grass and increasing problems with feathertop Rhodes grass and windmill grass. This project undertook a number of weed surveys to get a baseline measure of the level of glyphosate resistance in hard to control weeds of cotton farming systems.

This project aimed to develop increased weeds research capacity within the cotton industry and improve the knowledge and understanding of critical areas including:

• The current herbicide resistance status of weeds in the cotton system including awnless barnyard grass, feathertop Rhodes grass, windmill grass, fleabane and sowthistle.

• The impact of tillage operations for pupae busting on weed control in cotton systems

• Controlled environment studies to better understand the role of temperature, rainfall, growth stage and different populations on the survival of important weeds, especially awnless barnyard grass.

The project also incorporated the role of Technical Lead for Weed management within the CottonInfo team, as lead researcher. The project has worked closely with CottonInfo Regional Extension Officers (REO’s) to deliver extension messages and communicate results from herbicide resistance testing.

CSE1304 set out to test assumptions for refuges; tested if tolerance in addition to resistance could be a potential threat to Bt cotton efficacy and looked at ways to improve refuge governance. This project has identified some issues with refuge assumptions, and increased understanding of tolerance that will be presented to the TIMS technical panel for discussion.

While some assumptions for refuges such as moths from Bt and non-Bt refuges readily mate, and the population is not segregated were found to hold, others did not. It was found that much higher numbers of both Helicoverpa species are emerging from Bt cotton than expected. This suggests that 50% of all moths in Bt/refuge complex (ie excluding unstructured refuges) are originating from Bt cotton. This highlights the importance of both a healthy and attractive refuge, but also growing a healthy Bt cotton crop.

Susceptible Helicoverpa, especially in latter instars, could survive in Bt cotton by feeding on plant structures with low levels of toxin. While H.armigera may be more likely to develop resistance to Cry2Ab, H.punctigera may be more likely to develop tolerance to Cry1Ac. H.punctigera exposed to low levels of Cry1Ac toxins in later instars produced offspring with higher tolerance to Cry1Ac toxin; and those emerging from Bt cotton had higher tolerance to Cry1Ac. Exposure to both Cry1Ac and Cry2Ab concurrently lead to an increase in tolerance levels.

Some planned genetic studies of tolerant colonies were not able to proceed because it was identified that Cry2Ab colony had the HaR01 Cry2Ab resistance gene. It is likely the original 2011 susceptible colony had an undetectable level of the gene that increased in concentration with exposure to low level toxins. Tolerance may assist the survival of RS individuals, thereby assisting the spread of resistance, but this needs more investigation. Tolerance was found to decrease over generations when larvae are no longer exposed to toxins, so refuges may help to reduce the impact of both tolerance and resistance.

Narrow refuges did not detract from the attractiveness of pigeon pea, and attractive pigeon pea did not increase egg lays in neighbouring Bt cotton. Given the mobility of, and the ability of late instar pupae to survive and build tolerance (particularly H.punctigera tolerance to low levels of Cry1Ac toxin) , it was identified that larvae moving from non-Bt plants to Bt (eg deteriorating refuges to Bt cotton) was a threat. Recommendation to have Bt cotton and refuges separated will be raised with the Bt tech panel.

Pigeon pea attractiveness was found to be higher at the end of the season, meaning these refuges may act more like trap crops. The case for destruction of pigeon pea crops at the end of the season will be raised with Bt tech panel.

While satellite imagery is not useful in identifying field attractiveness at a particular point in time, it does indicate season-long vitality and shows potential to check for problematic refuges remotely, although more work would be needed to fully develop techniques.

Moths of the genus Helicoverpa are the most destructive pests in Australian cotton. They have been also some of the most difficult to manage because H. armigera (in particular) has quickly developed resistance (within 5-8 years) to nearly every insecticide used in its control (Whitehouse et al. 2007). To hinder H.armigera developing resistance to Bt cotton, a Resistance Management Plan (RMP) was put in place when Bt cotton was first used commercially in Australia in 1996. As this was over 15 years ago, the RMP has been successful. Nevertheless, in light of the development of resistance to Bt cotton by H. armigera in other parts of the world (Tay et al. 2013) it is important to remain vigilant and keep testing the tools used in the RMP.

A key tool of the RMP is the use of refuges. Refuges help maintain the potency of Bt cotton by producing unselected Helicoverpa moths that mate with any resistant moths emerging from the Bt crop, thereby diluting their genetic contribution to the next generation and slowing the development of resistance.

Refuge governance is based on models with assumptions that are difficult to test on farms. The Helicoverpa Genome Project has mapped all of Helicoverpa’s genes, making it easier to test two assumptions on the frequency of resistant (R) and susceptible (S) genes, and on the degree to which moths mix both within valleys and between Bt cotton and its refuges. If these assumptions are incorrect, then refuges may be underperforming.

Although refuges are designed to counter Bt resistance developing from genetic mutations, a recent CRDC project (03UA002) showed that under laboratory conditions, the exposure of Helicoverpa to low, non-lethal doses of Bt toxins over 12 generations can cause H.armigera to develop inducible tolerance to Bt toxins, to the extent that they are not killed by levels of Bt toxin fatal to susceptible H.armigera. As stressed Bt cotton plants may produce less toxin, and some parts of the plant produce low levels of toxin, inducible tolerance could be another pathway by which Helicoverpa could survive on Bt cotton. An aim of this project is to test the likelihood that inducible tolerance could occur in field crops of Bt cotton, and if so, if refuges could reduce that risk.

For refuges to counter genetic resistance and inducible tolerance to Bt toxins, they must be working optimally on farms and produce as many moths as possible. To do so refuges need to attract sufficient egglays, and then support as many of the resulting Helicoverpa larvae as possible until maturity. For many growers it isn’t clear if their refuges are countering the development of resistance; how to improve the productivity of their refuges; or how to measure the effectiveness of their refuges in order to improve efficacy. Monitoring refuge productivity is a challenge, with current reporting often at odds with on farm realities. A remote method of checking refuges could be used to identify refuges facing difficulties, which could be then ground-truthed. The ultimate aim of this work is to incorporate best management practises into myBMP to improve refuge governance and also to develop better monitoring techniques to identify under-performing refuges which may need more assistance.

The overall aim of this project is to improve the ability of refuges to counter both the threat of resistance developing via genetic mutation, and the potential threat of crop failure via inducible tolerance. By accessing and countering these threats while concurrently developing better refuge management and benchmarking techniques to improve refuge governance, the ultimate aim is to avoid the cost of losing Bt cotton efficacy.

The Cotton Research and Development Corporation (CRDC) has made significant R&D investments in soil health research over recent years.

Initially the focus was on nutrition: studying nitrogen, phosphorus, potassium, iron and zinc. The research focus then moved to soil physical fertility: studying compaction and ways to manage this, including gypsum, deep ripping, rotations, minimum tillage, permanent beds and controlled traffic rows using GPS technology. More recently the research emphasis has moved to soil biology: What do soil organisms do, can they enhance fertility and what can we do to promote their presence.

This study aimed to examine current knowledge and understanding of soil health and management issues. It also aimed to identify the cotton community’s “soil health” needs in order to enhance the research and extension effort in this area.

The Soil Health survey extended from Hay in the south, to Emerald in the north. Thirty farmers were interviewed during July 2005 at: Hay, Hillston, Narromine, Trangie, Warren, Breeza, Gunnedah, Narrabri, Pilliga, Moree, Mungindi, St. George, Dalby, Warra and Emerald. All interviews were face to face except for the Emerald growers and one Moree grower, who were interviewed by phone.

If we exclude growers who are currently using poultry and feedlot manure, three growers were currently involved in utilizing alternative approaches to biological soil health. Of the remaining growers, some were open minded about alternative methods but felt that without good scientific rigour to support the products currently on the market, they were reluctant to take these products on board. Other farmers in the survey expressed a degree of caution towards the subject of soil health.

‘Soil Health’ is seen as such a general term, it is understandable that there are a variety of definitions. It may be more useful to call it ‘Soil Biology” or ‘Soil Ecology’, as a ‘healthy’ soil encompasses physical, chemical and biological properties. Hence the growers in this survey all seemed to have a varied understanding of what ‘Soil Health’ means to them.

However, they all agreed that it embraced a number of factors: It needed to be an active soil; to have good structure with plenty of organic matter; be well balanced nutritionally and to be rich in macro and micro organisms. It needed to be a soil that was easy to manage, grow good crops and be able to repair itself.

Growers were very comfortable discussing the physical and chemical aspects but were a little unsure about biology and admitted that they had seen very little scientific information on this topic.

Growers spoke about a range of factors which they thought were key to good soil health including rotations, organic matter, organic carbon, sodicity and nutrition.

Their opinions on the factors which can limit production included: nutrition, sodicity, soil biology, salinity, soil management, disease, Vesicular Arbuscular Mycrorhiza (VAM), residual herbicides, organic matter levels, waterlogging, water use efficiency and education.

Vews of which management practices can affect soil health included: rotations, stubble management and organic matter accumulation, care of soils under wet conditions, min-till, permanent beds, controlled traffic systems using GPS technology and field architecture relating to waterlogging were felt to give the biggest benefits in the short to medium term.

Growers displayed a certain amount of cynicism towards soil health products and programs. A small number were more supportive. They discussed a range of topics relevant to commercial products and programs including commercial soil testing for soil health, the use of soil health products and their profitability.

The majority of growers have a basic understanding of VAM. Current drought conditions, forced long fallows and the fear of long fallow disorder heightened grower awareness of VAM and the consequences of low VAM numbers.

On environmental issues growers were very satisfied with the information received and practices in place by CRDC and the Cotton CRC. For example: breeding.

This paper is aimed at presenting some aspects of this debate and seeks to answer the following questions: *Are the dryland industrys needs being met by the spin-offs from the current breeding program? *Given the success of the irrigated breeding program, is there a need to duplicate it to cater for the dryland cotton industry of the future?

Experiments to establish if the use of GM cotton has an impact on the soil microbes that grow in association with the plant roots has shown that there are no differences in number or function when compared to non-GM conventional cotton under field conditions. However, varietal differences were observed in both the field and glasshouse.

Experiments were run in cotton field trials over three seasons at the Australian Cotton Research Institute, near Narrabri, NSW. Rhizosphere soil, the soil that makes contact with the root and is directly influenced by the plant, was routinely sampled. Bacteria and fungi were recovered from this soil using traditional cultural techniques on several selective agar media and found not to differ in numbers between GM and non-GM. Experiments to investigate activity (measured as respiration) and amount of microbes (assessed as biomass) also showed no differences between the GM and non-GM plants under our experimental conditions. A desk top environmental impact assessment of insecticide use, made during the project, also indicated that GM cotton is less environmentally damaging than it’s conventional counterpart and their associated pesticide usage. With these two considerations in mind, GM cotton would appear to be the more sustainable and less environmentally harmful option of cotton production currently available in Australia.

Despite no significant GM to non-GM differences being observed in microbial biomass and activity, cotton varietal differences were noted during the course of the project. Molecular work, using a technique known as DGGE to produce a ‘fingerprint’ of microbial communities, produced evidence that varieties were selecting specific microbial populations in association with their roots. This was apparent from glasshouse trials conducted in Narrabri and Adelaide, on both cotton and non-cotton soils. Lack of consistent differences under field conditions could be attributed to stresses due to environmental factors such as temperature, water availability and plant physiology differences between glasshouse and field.

Varietal differences were again noted when border cells produced by cotton cultivars were assessed. Border cells are produced at root tips and are involved in environmental sensing by the plant. Border cell numbers were much lower in many of the currently available GM and non-GM cotton varieties. Tested varieties produced between 2000 to 12000 border cells per root tip. Reasons for this varietal difference were unclear, but there was evidence that border cell number plays a role in Fusarium resistance.

Assessment of the impact of leaf drop following defoliation indicated that this sudden carbon deposit onto the soil significantly/dramatically increased adjacent soil biota. No consistent varietal differences in the microbial biomass levels were observed, however, the composition of microbial communities associated with decomposing leaf residues was influenced by variety. This work does raise questions regarding the functional significance of this explosion of biota and if management could alter or better utilise this process. Future research to fill this knowledge gap is recommended.

Establishing recommendations for improved farm management and soil conditioning through cotton variety selection is currently not possible. This is because we still know very little about the soil biological environment. Further investigation of the soil biota is warranted to develop tools to predict how soil responds to changes imposed upon it through either crop selection or management. Additionally, over the course of this project we have seen clear evidence that cotton variety choice can have an impact on the soil microbiota. With the yearly release of new varieties the extent and significance of this impact is difficult to gauge. Establishing the extent and nature of these variety differences and their significance for soil microbiota has formed the basis of a new CRDC funded project.

When it comes to varieties 1 don't believe that the growers needs will ever be totally met, we are always looking for improvement in varieties to satisfy, not only the ever tightening cost-return squeeze, but we have to satisfy the changing requirements of the market place.

Agenda Fifth Australian Cotton Conference ,Hotel Conrad and Jupiters Casino,Broadbeach, Gold Coast, Queensland