In 1998 when we first started Benchmarking we were not sure what we were going to find. At the time the Darling Downs In particular had suffered a number of years of rising insect pressure and insect control costs, Ingard was just being released with mixed results and insect resistance was rising rapidly. The long term economic sustainability of growing cotton was being threatened. The objective we set at the beginning of the CotBench. Benchmarking Program was &quote;to provide cotton growers with a quality analysis, as well as the motivation and support to evaluate their cotton operation's gross margin and to take action to improve their profitability and sustainability'

In recent years community interest in the development of the irrigation industry throughout Australia has increased significantly. furlong these industries it has been the cotton industry that has been most notable in its water infrastructure and management systems development. This has happened during a period in which governments, particularly the Federal Government, have retreated from infrastructure development. So we in the cotton industry, as well as those in other irrigation industries, have picked up the ball and undertaken massive private investment in water infrastructure development. Naturally the private investor has been most keen to invest in schemes that are not subject to government controls and legislation. As a result, we have seen particularly in Queensland in recent years, a dramatic increase in the numbers of on-farm storages built to harvest unregulated overland flow. Now in 1998 community scrutiny of privately developed water infrastructure is higher than ever before and the development of appropriate regulation measures, if any at all, has become a major challenge for every State government.

The Australian cotton industry now has a new version of the SOILpak manual.

The silverleaf whitefly (SLW), Bemisia tabaci B-biotype, was first discovered in Australia in 1994 (Gunning et al 1995). SLW is a major pest of cotton and other crops in many overseas countries and poses a considerable threat to cotton in Australia. SLW is the second biotype of B. tabaci be found in Australia. A closely related indigenous biotype (IBW) was first recorded from Australia in 1959 (Carver and Reid 1996). Molecular phylogenetic studies (De Barro unpublished data) indicate that IBW is unique to Australia and some near Pacific Island countries. IBW is an efficient vector of tomato geminiviruses that were extremely damaging to the Northern Territory tomato industry, but unlike SLW does not cause feeding related damage. Since its detection, SLW has spread widely in New South Wales and Queensland. However, its spread into the cotton growing regions of both states has been slower than in the areas dominated by vegetable horticulture. Given the threat posed by SLW to cotton in Queensland a monitoring system using surveys was established and has been run over the past two years

Traditional methods of generating soil information on the field scale have involved the design and adoption of soil sampling regimes and laboratory analysis. Due to the time consuming nature of this approach only limited soil information can be collected. Nevertheless, soil maps are generated and inferences about the spatial distribution of soil properties, and soil condition etc. are made from this cursory information. Unfortunately, the use of such maps leads to errors in interpretation and possibly soil management. In more specific investigations such as soil salinity assessment and determination of irrigation\drainage efficiency more detailed quantitative soil information is required, in order to provide the necessary information to manage soil salinity or related problems.

Has the introduction of Bt genes into the cotton plant affected its capacity for compensation after insect damage? This question is relevant for three reasons. First, and most obviously, Bt cottons remain vulnerable to non-Iepidopteran pests, including thrips and minds. Second, they are susceptible to Helicoverpa spp. when Bt efficacy drops because of crop ageing. Third, under some (yet undefined) environmental conditions, Bt efficacy can be low even in young crops, and we have seen fruit shedding in young commercial Bt crops that has been attributed to Helicoverpa damage. We assessed the degree of tolerance of Bt cotton to actual and simulated insect damage in three field experiments carried out at ACRl in 1996/97. Yield and maturity responses to damage of Bt cottons compared well with those of conventional varieties. The introduction of Bt genes into cotton does not seem to have reduced the considerable capacity of the crop to tolerate insect damage, and this attribute should be considered in the development of pest management strategies for Bt crops.

In some major producing countries, up to half of the returns to cotton farmers come from government subsidies. In some cases, the subsidies are counter cyclical so that the recipient farmers never face the realities and disciplines of the world cotton market. These countries also maintain substantial barriers to imports of yams, textiles and clothing. The consequences of highly protective policies for non-subsidising countries are disastrous. When international prices start to fall, there is no supply response in countries, such as the United States, which heavily subsidise their producers. The subsequent over-supply greatly exacerbates the downturn in world prices so that all the adjustment is forced onto non subsidising countries. This in nun causes significant social disruptions, particularly in developing countries.

VAM are important in the growth of cotton and the production of lint. VAM are a normal part of cotton plants and they are usually present in the roots. Only in their absence do we realise their importance. In syndromes like Long Fallow Decline or growth decline following land-planing, reduced plant growth and cotton production coincide with reduced VAM in roots, and reduced phosphorus content in mature plants. While we realise their importance, VAM are difficult to study. VAM are an association between soil-borne fungi and the roots of most plants. For the fungi, the association is obligate, and growth of the fungi relies entirely on the host plant. We cannot see the fungi in soil, nor in the roots of the plant unless we use laboratory based processes. Thus study of the fungi and their effect on plants requires specialised equipment and trained staff. CRDC has funded VAM research for several years, This paper summarises the research on the population biology of VAM fungi in cotton soils in eastern Australia completed at the University of Sydney.

(I) To continue and develop the work begun in UsQ6C which focuses on residue handling in back to back cotton and rotation crops while optimising the control of diapausing heliothis pupae. (2) To visit growing areas (irrigated and rain fed) and confirm a basis for other machinery needs in the industry, including planting and cultivation equipment. (3) Field test equipment changes. (4) Seek backing from commercial entities to limit funding drain of research monies. (5) Pursue the involvement of commercial manufacturers where appropriate to help in the adoption of improved technology. (6) To monitor commercialisation of a fully tested computer based guidance system

Farming systems are continually attracting interest amongst the growing community, since input costs are continually increasing and returns behave in a cyclic nature. Growers are now stepping back from the enterprise, to assess the production unit for agronomic, economic and environmental issues before selecting the rotation crop for the farm, endeavouring to achieve the most sustainable production system. This has research dollars invested, to examine the effects of rotation crops on the cotton production system.