Precision agriculture (PA) as a crop management philosophy was first hypothesised in the early 1990's as a way of utilising the development of technology such as the Global Positioning System (GPS) and variable-rate crop applicators to produce crops in a more sustainable fashion. Historically, fields have been managed as homogeneous units, receiving equal amounts of crop production inputs. The rational behind precision agriculture, or site-specific crop management, is that by identifying within-field variability in crop and soil attributes (e. g. cotton yield, soil nitrogen levels) and their origin, it then becomes possible to optimise crop production inputs such as pesticides and fertilisers on a point-by-point basis. Implicitly, this lowers the potential for the over and under-application of these crop production inputs, thus increasing profitability for the grower whilst simultaneously reducing the probability of adverse environmental impacts such as groundwater or surface water contamination from the over application of agrochemicals. While progress in developing a filmy integrated PA system has been slow over the past decade, research from a number of industries worldwide has highlighted there will be many benefits to be galled from adopting such a system. Secondly, triller technological advances in airborne imagery collection, on the-go sensor development and computer processing techniques means there is an unprecedented number of tools available to aid in crop management. Furthermore over the last decade it has emerged that each country and crop will its own unique requirements within the larger framework of PA.

Cotton fibres, or lint, are very long single cells containing almost pure cellulose. The fibres develop in the weeks after flowering from single cells on the surface of the young seed. Each fibre cell is single at first but elongates and develops rapidly, eventually forming the mature cotton fibre. These processes require the ordered expression of genes which mate enzymes, structural proteins and signalling molecules that together determine the properties of the fibre. Domestication has modified fibre development to produce cotton varieties with greatly improved fibre length, strength and quality. However, the selection and breeding of plants with desirable fibre characteristics is slow and expensive. As such, future crop improvement is likely to depend upon genetic engineering and the cotton industry has been a leader in research and commercialisation of transgene technology, with momentous consequences for the agronomic properties of the crop such as insect and herbicide resistance. Whilst fibre improvement has not been the initial focus of the application of DNA technology, research to this end has been vastly accelerated in the last decade, particularly in the USA. The recent formation of the international Cotton Genome initiative between scientists in USA, France and Australia represents a global effort to develop a saturated and fully integrated genetic and physical map of the cotton genome. Gene discovery is also advancing rapidly, with the release of over 20,000 partial gene sequences (called ESTs) from elongating fibres of both diploid and tetraploid cotton, and the use of CDNA microarrays to facilitate global expression profiling.

White speck neps cause significant financial losses to the textile industry and the following studies look at several factors that may affect white specks. Processing factors, such number of lint cleaners used at the gin, mill card settings, and combing are studied, as well as varietal differences, to see the effect on white specks in the finished fabrics. This paper examines the white speck phenomena as seen in the US and Australian studies. The first study has 4 extreme US varieties that were grown specifically to produce different levels of white specks. In this study, it happens that the tandem card was improperly set during insulation results in much higher levels of white specks than single carding, showing the importance of proper settings and maintenance. The second study looks at 26 US leading varieties studied (LVS) by AMS (Agriculture Marketing Service of the USDA, they measure what are perceived to be the important quality measurements on all cotton produced in the USA). This study also includes five extreme varieties grown in the same field (similar to the first study) and processed identically in the gin and mill. This shady also compares carding with combing. Four varieties from the 26 Leading Variety Study by AMS were carded and combed and the fabrics are analysed for white specks. The final two studies are collaborative studies between US and Australia. The cottons were gown in Australia and the studies compare ring to rotor spinning and different levels of lint cleaning at the gin. The first year used small seed cotton samples (300lbs) and the second year used full modules of seed cotton. Combing was found to reduce the white speck problem, while other processing seems to open and separate the immature fibers spreading the white speck problem. Ultimately we would like to develop strong predictions of white specks from high-speed instruments that test bale fibers, and have the white speck potential included in the classification of cottons.

As with all post mortems the aim is to work out what happened and why. By understanding this we will be better able to address the issue of how much of Australia's cotton will be affected by this pest and what is the level of the threat. A good starting point is the basic set of requirements for a silverleaf whitefly outbreak and here we need to consider the &quote;outbreak pyramid&quote; (Fig. I, modified after Peter Ellsworth, University of Arizona, Maricopa). The two most critical factors are climate and cropping systems, without both of these an outbreak is unlikely.

Helicoverpa spp remain the most important pest in the Australian cotton industry. They are resistant to most of the insecticides used by the industry. The cotton industry is determined to reduce their independence against this pest. As a result there is a strong push by the industry in recent years to adopt a true IPM program in order to minimise insecticide use. Semio (signalling) chemical that may impact on pest behaviour are currently being studied to isolate potential chemicals for efficacy against cotton pests. Chemicals on the leaf surfaces of refuge crops, cotton cultivars and other plant species will be isolated , purified , formulated, bio assayed against cotton pests and the potential ones deployed in cotton IPM. Field and mesh house trials of different plant species and refuge crops have been screened for oviposition and feeding preference against Helicoverpa spp adults and larvae. Results, so far showed that several less preferred crops and plant species deter Helicoverpa ssp. adult oviposition and also cause mortalities in the larvae. An unidentified plant, codenamed &quote;PlantX&quote; was found to reduce Helicoverpa spp. Egg lay by 94 %. The top, middle and base leaves caused 89, 78 and 89 % mortalities respectively to H. punctigera second stage larvae. The seeds also caused 74% mortality to the larvae. Further studies are continuing to extract toxic compounds in PlantX and bioassay it against Helicoverpa spp. If successful a new IPM tool will be developed for cotton growers for use in IPM programs.

Two key hormones, ecdysone and juvenile hormone, control metamorphosis and moulting in insects. Stated simply, the role of juvenile hormone in insect development is to determine the type of moult that is undertaken by the insect. The presence of juvenile hormone maintains juvenile characteristics and prevents development of the adult form (Kumaran, 1990). Very low levels of juvenile hormone are found in the insect immediately preceding a larval to pupal moult, while absence of juvenile hormone in the insect leads to a pupal to adult moult. There are at least six fonts of juvenile hormone that occur alone or in combination across different insect orders and developmental states. Juvenile hormone III is the most commonly detected form across insect orders. However, there is some evidence that in the higher Diptera such as D. melanogaster JHIII is a precursor for an alternative form of the hormone, juvenile hormone III bisepoxide (Richard et al 1989).

Cotton is the most important textile crop due to its cellulose-enriched mature fibres, single celled hairs derived from ovule epidermis at anthesis. Despite the great potential for increasing cotton productivity through genetic engineering of fibre development, little progress has so far been made in this area. This is in sharp contrast to the success of pest and herbicide resistant transgenic cotton that have already made a large impact on agriculture in both the U. S. and Australia (1). The major impendence to fibre engineering is due to our poor understanding of the biology of the cotton fibre, particularly, the identities and functions of genes controlling various fibre development processes. Cotton fibres are metabolically active cells in utilising hexose or its derivates from phloem-imported sucrose for its initiation, elongation and cellulose synthesis (2,3,4,5). Sucrose synthase (SuSy)is the key enzyme in cotton fibre to break down incoming sucrose into fructose and DDP-glucose (2,3). The latter is the immediate substrate for cellulose synthesis (6). However, previous evidence on the role of SuSy in cotton fibre development is largely correlative in nature (2,3,4). Here, by using reverse genetic approach, we have now demonstrated that SuSy indeed plays a crucial role in cotton fibre initiation, elongation and cellulose synthesis.

The CSIRO Advanced Lines Trial(ALT) has been run cooperatively by CSIRO and DPIQ for 26 years and is used as the last stage in our breeding line evaluation. Early generation testing following single plant selection involves unreplicated progeny rows at the Australian Cotton Research institute, further progeny row tests and multiple row replicated trials at a limited number of farm sites. At each stage, lines with poor seedling vigour, disease susceptibility, poor fibre quality or low yield are removed from further testing. The ALT involves 13 irrigated sites in all major cotton growing regions in Australia. Management is normal commercial practice including full insect control Entries in the ALT include promising breeding lines and commercial standards. Ingard varieties are included in the ALT even though the trials are conventionality sprayed. Their performance indicates yield potential relative to their conventional counterparts and also gives an indication of the insect pressure experienced. Plots consist of three or four rows from 10 to 14 metres long and four replications are used. The centre rows of all plots are harvested with a modified picker, the seed cotton weighed and a subsample is taken for ginning at Biloela or Narrabri and fibre quality analysis at Narrabri. The most promising lines are retained in the scheme and also seed increased. In this way, by the time good performance is confirmed, sufficient seed is available for large scale testing and final seed increase for cornmercial use.

Plant diseases are currently threatening the productivity and sustainability of the cotton industry. Regular disease surveys in NSW have enabled accurate observation of the changing distribution and severity of diseases over time. The relative risks are low for bon rots, Alternaria leaf spot and bacterial blight, medium for seedling disease and Verticillium wilt, and high for black rootrot and fusarium wilt. Issues that need to be addressed include regional differences, potential new threats, and the complexity of pathosystems (pathogens x hosts x fields x regions). Research should include (1) continued investigation of factors contributing to the spread and severity of diseases and (ii) further development and evaluation of tools for integrated disease management.

Interest in Integrated Pest management (IPM) and Area Wide Management (AWM) continues to increase within the Australian Cotton industry. The costs of chemical control, coupled with pests developing increasing levels of insecticide resistance and an awareness of the potential impacts of sprays on the neighbouring environment have led many Australian cotton growers to consider new approaches to pest management. AWM an approach which acknowledges that pest and beneficial insects are mobile, and that the management regimes to control pests imposed on a given field are likely to alter the abundance of beneficial organisms and levels of insecticide resistance in the surrounding locality. By communicating and coordinating strategies, growers within an AWM group have better opportunities to implement ERM strategies like those outlined in the Integrated Pest Management Guidelines for Australian Cotton (Mensah and Wilson 1999).