Total dependence on broad spectrum insecticides led to nerve insensitivity resistance in Helicoverpa armigera and, eventually, to the collapse of the previously successful cotton industry at Kununurra in 1974. The final year of production saw an average of 40 insecticide sprays per crop, at which stage the industry was no longer economically or ecologically sustainable (Michael & Woods, 1980). New research commenced in 1994 to evaluate the potential for successfully reintroducing cotton to the Kimberley, but within a biologically sustainable framework. The new approach aims to develop pest management security for a future industry by minimising the impact of pest species, minimising pesticide inputs and enhancing the benefits of naturally occurring predators and parasitoids. Key features of the new strategy include winter cropping, the use of transgenic varieties, resistance management policy and an integrated pest management (IPM) production philosophy (Strickland and Constable, 1995). The preliminary studies reported here were based on conventional cotton varieties due to the unavailability of transgenic types. However, in 1995, additional observations were made on the insect fauna in a transgenic cotton crop grown for seed production on behalf of Cotton Seed Distributors by Mr T Sass-Nielsen. The aim of the studies was to obtain basic data on insect abundance and impact on yield for contemporary cotton varieties grown during the winter months at Kununurra. The intention was use this data as the basis for developing more detailed research on IPM systems, with transgenic varieties, when they became available from 1996 onwards.

The imminent release of transgenic cotton brings with it the need for some changes in production techniques to provide effective refuges as part of the pre-emptive resistance management strategy (see papers by Fitt and Forrester, this proceedings). Refuges are clearly the most unusual aspect of the strategy. Here we briefly describe our work to quantify the value of different types of refuge for Helicoverpa where the chief measure of value is the number of moths produced per unit area overtime. A refuge which produces twice as many moths is twice as valuable for resistance management, all else being equal.

We tested the suggestion that early season damage may limit the crops subsequent exploitation of moisture in the skip row, which may in turn 11nxit the crops ability to recover. Over two seasons the recovery response of dryland double skip cotton was investigated, where artificial damage was used to simulate damage caused by thrips or Helicoverpa. Treatments included defoliation and/or tip damage. None of the treatments significantly affected yield, however there was a consistent trend towards lower yield in heavier damage treatments. Moisture extraction from the plant row and skip did not appear to be correlated with plant damage, although seasonal weather conditions may have affected this result. Earliness was not specifically assessed but heavy damage treatments appeared slightly delayed. These experiments suggest that factors other than early season damage may be affecting the plants ability to extract moisture from the skip row. Further work in this area needs to be conducted to assess the impact of damage on skip row cotton and factors affecting extraction.

Irrigation of cotton while substantially increasing yields, presents several new problems to the industry. Perhaps the most immediate of these is deep drainage, which in turn poses water use efficiency and groundwater pollution problems. Excess root zone salinity and soil structural problems due to irrigation should also be issues of great concern. There are many factors that contribute to the development of these problems, the most crucial of which is the irrigation water quality and the soil properties. The expansion of cotton into areas such as the Darling Downs has seen the increasing use of higher conductivity, occasionally sodic groundwater for irrigation. With this trend set to continue, and with significant quality decline in surface waters predicted (MDBC Salinity Audit 1999), the need to investigate the extent of the problems this will cause is even more pressing.

Since 1992, CSRO Cotton Research Unit has conducted large scale insect management trials in the upper and lower Namoi Valley. The trials have utilised large field areas on privately owned farms, generally in collaboration with a commercial consultant. Over the past 4 seasons, an average of 3 trials per season have been conducted, covering both long and short season irrigation areas and dryland production. The primary aim of the trial has been to field test and validate the insect management decision support system entomoLOGIC. This included testing the functionality of the program and also establishing its value as a tool for monitoring field trials. The second aim of the work was to compare different pest management approaches, including a range of &quote;hard&quote; and &quote;soft&quote; options. The aim of the &quote;soft option&quote; was to preserve beneficial insects for as long as possible to determine whether their impact on pest numbers was sufficient to reduce the total number of sprays. In all cases, the aim was to produce the maximum possible yield and earliness, regardless of the treatments imposed. This was important considering that the trials were conducted on a commercial scale on private farms.

Cotton integrated pest management (IPM) is a constantly evolving approach to managing insect and mite pests in cotton. The goal of IPM is to integrate all means of managing pest populations with the aim of reducing insecticide use whilst maintaining profitability (IPM Guidelines, 1999/00). The Australian cotton crop is subject to a range of pests that often show a wide range in abundance between seasons. Whilst a number of new relatively selective chemical control products have become available the increasing scrutiny on chemical use by regulators has made application of some chemicals, both new and old, very difficult. This has provided a strong motivation to use more environmentally friendly insecticides and to reduce overall insecticide use. The rapid adoption of the 'new' chemistry by growers and consultants is reflected in an increasing awareness of the value of beneficial insects in the Australian cotton agroecosystem. Cotton IPM in Australia is not easy; indeed pest management in cotton has not been easy since the single tactic of programming Synthetic Pyrethroids began to fail in the early 1980's. Insecticide resistance and environmental impact are the legacy of over reliance on a limited number of control options for heliothis. Resistance, increasing insecticide costs and the need to reduce environmental pollution are driving the continual development of a management approach that seeks to combine all the 'tools and tactics' available to growers and consultants to deal with multiple pest species in various combinations. The objective of IPM is to use all the tools in the toolbox in a way that creates a balanced approach that results in an overall reduction in pesticide use, hence reducing environmental problems and resistance while maintaining profitability. Successful cotton IPM in Australia takes a commitment to planning so that all the tools and tactics that are available can be used effectively

Over the last six or seven years, seasonal forecasts provided by the Bureau of Meteorology's National Climate Centre have been based on statistical relationships between rainfall and the EI Nino-Southern Oscillation (ENSO) phenomenon. The Southern Oscillation Index (Sol), a measure of the atmospheric pressure differences between Darwin and Tahiti, has been used extensively as an indicator of ENSO events. Significant correlations with the Sol, however, are limited to certain seasons and locations only, and strong relationships are often only found once an ENSO event is well developed. In particular, correlations over the period from late spring to early autumn in the cotton growing areas of eastern Australia are generally quite poor. Forecasts have also been restricted to 3 month seasonal average values commencing immediately from the time of issue. Some improvements in statistical techniques using trend and phase information has extended the use of Sol based forecasts to provide coverage for most of the year round, and useful assessments of overall conditions are provided, but for cotton growing areas the skill has not increased to the point of bulletproof reliability. What then can be expected in the future?

The Queensland Department of Primary Industries is currently investigating IRM techniques for heliothis in cotton and some vegetable crops. The research includes evaluation of native egg parasitoids as biological control agents of heliothis. In 1994 a strain of Trichogramma pretiosum was obtained from heliothis eggs on sunflowers at Kununurra (Western Australia). The results of initial field testing of this species of wasp as an in inundative bio control agent are provided below.

Perhaps the best way to answer this question is to firstly define what is meant by an integrated pest management (IPM) program. Basically an IPM program should - I. Provide effective control of the pest complex. 2. Reduce reliance on synthetic insecticides. 3. Be economically viable. 4. Be simple and flexible. 5. Utilise compatible control measures. 6. Be sustainable. 7. Have minimal harmful impact on the environment, the producer and consumer. Agriculture continues to change in response to the needs of society (Dent, 1995). The development of IPM is often explained as a response to problems facing farmers that result from overuse of insecticides, such as pesticide resistance and secondary pest outbreaks. However, increasingly the development of IPM reflects the expectation of society for pest management systems that do not degrade the environment or cause health problems. The primary aim therefore of an IPM system is to reduce reliance on synthetic insecticides

The cotton industry in Australia continues to be Tenant on insecticide and fertiliser inputs to maintain yields. Over the past decade the off farm movement of these pollutants in runoff water has created a number of environmental issues of concern for the industry (Edge; 1996). In particular, pesticide can be transported off farm in solution or attached to suspended sediment, which are a major factor in pesticide contamination of rivers particularly as storm runoff (Schoefield et al1998). As part of a major R&D program undertaken by the cotton industry, the transport mechanisms and fate of cotton pesticides and nutrients were investigated to address the contamination issue. Key findings from the work identified the high-risk period as early season and highlighted the importance of storms and sediment in moving pesticides off-site and the importance of ground cover in reducing movernent (Simpson et al 1996 and Silburn et al 1996). At the completion of the program, the cotton industry had a much better understanding of the process of pollutant movement from farm to river. However, few proven practical techniques were available to growers to reduce the risk of off-site movement of pollutants in runoff.