Central Queensland currently enjoys an ascochyta blight free status, however the use of chickpeas as a winter trap crop has created a potential risk for the introduction of the disease. To address his problem we evaluated three winter active legumes (popani vetch, namoi vetch and field peas) for their suitability to be substituted for chickpeas as a spring trap crop in central Queensland. Field peas were found to be highly attractive to egg laying Helicoverpa spp. moths, carrying on average 50-70 eggs per metre row for most of September, the period for which a trap crop should be most attractive under CQ conditions. Egg survival on field peas was low with only 27 +/- 3.5% of eggs surviving to hatch as opposed to 73 +/- 2.9% egg survival on chickpea. The results suggest that field peas may be a viable trap crop alternative for chickpeas that would avert potential problems associated with ascochyta blight in this region.

Petroleum spray oils (PSOs) have been used for control of a wide range of pests and are now an essential part of many integrated pest management programs (IPM) for agricultural and horticultural crops (Simanton and Trommel1966, Riehl 1981, Johnson 1985, Lee et al. 1991, Beattie 1995, 1997, Rae et al. 1996, 1997). PSOs have little impact on natural enemies of crop pests and therefore can complement the activity of beneficial insects in crop systems. However, the use of PSOs in the cotton industry is limited due to the risk of PSO induced phytotoxicity which is related to the high molecular weight of the oils (Riehl 1969). Recent research on citrus and a range of other horticultural crops has led to the development of new technology in UV light protectants, which reduce the risk of damage to plants.

In developing strategies for insect pest management growers and consultants have demonstrated that adopting a more dynamic approach to insect thresholds is more important than using any predetermined threshold. In combining dynamic thresholds with the use of less disruptive insecticides and the conservation of beneficial insects growers have be able to improve farm profits. When adopting a flexible approach to insect pest management it is important to monitor crop growth rates and fruit development to avoid excessive periods of crop damage. Acceptable damage levels will vary depending on growers yield expectations and climatic conditions, which will determine the seasonal length. Assessing fruit load in conjunction with regular insect monitoring provides significant benefit when making insect management decisions. This is particularly valuable when a range of insect pests are presenting the crop such as mirids and Helicoverpa.

Attract and kill formulations are ideal tools for inclusion in IPM strategies to control insect pests, as they can be targeted at a single pest species without affecting beneficial insects, or creating secondary pest outbreaks. Field studies with attract and kill formulations using pheromone for H. armigera male moths indicate that contact rates with the basic formulation were very low, but manipulation of visual stimuli and lure presentation could greatly increase contact rates. There were no deterrent effects caused by inclusion of a pyrethroid insecticide in the pheromone formulation.

Predatory arthropods are important in cotton IPM programs and planting a diverse range of crops may increase the on farm bio-diversity of predators. In some growing regions, it is common for large-scale cotton monoculture to be planted. Mixed cropping is likely to increase the bio-diversity and abundance of predators which may assist in increasing the natural control of pests. It is Important that the potential number of predators produced in different crop habitats is known. Specific crops can then be planted to enhance the numbers of key predatory species. Knowledge of the types of predators produced from different crops is important because some predator species are more significant natural enemies of pests than others. The research presented here provides information on the numbers and types of predators harbouring in a range of crops on a Darling Downs dryland cotton farm.

In Australia, premature senescence (PS) is occurring with increasing frequency in cotton crops. By the time PS is noticed, it is generally too late to take corrective measures and the use of plant tissue testing as a diagnostic tool has not been widely successful in predicting K deficiency (Kerby and Adams, 1985). Therefore, it is important to detect beforehand susceptible fields, so that timely action can be taken to avoid substantial yield losses, as insufficient K is believed to be one of the main contributing factors of PS.

The Bourke region has experienced a dramatic expansion of irrigated agriculture, especially cotton production, over the last decade. For sustainable agricultural production, quantitative soil information is required for effective land management and environmental planning. There is therefore the need for updating the soil resource information of the region. Soil sodicity and structural stability are two soil quality indicators specifically investigated in this study. The study is aimed to assess the current levels of soil sodicity and aggregate stability in order to predict spatial patterns of these soil attributes with the view of identifying the risk zones. The effect of land use on the soil quality indicators is examined.

Field trial examining the use of Bacillus thuringiensis (Bt) foliar sprays on transgenic and conventional cotton varieties showed various levels of Helicoverpa control and impacts on beneficial insects. Quantification of Bt protein concentration at various growth stages of transgenic cotton varieties and bioassay with field strain of H.armigera revealed great variation of concentration and efficacy.

Elsewhere in this proceedings I have stated that the cotton industry in Australia is undertaking a journey towards the adoption of a true IPM. The industry has come a long way from indiscriminate use of synthetic insecticides to realising the major role natural enemies of cotton pests particularly predatory insects play in cotton IPM. Many beneficial insects such as predatory beetles, bugs, lacewings, spiders and parasitoids have been recorded in cotton crops in Australia. However, the potential value of these beneficial insects have riot been fully exploited in cotton pest management. This is due to the lack of understanding of the efficacy of these beneficial insects, lack of techniques to maximise their abundance and effectiveness, and the continuous use of broad-spectrum insecticides on cotton crops against major pests. Cotton fields across Australia are strictly monoculture and can affect the activities of beneficial insects. In such agro-ecosystems, pest populations increase, minor pests become major pests and non-pests become pests. This is because the food, hosts, prey, and hibernating or overwintering sites of the natural enemies are reduced thus affecting biological control (Mensah, 1997, 1999). Natural enemies of cotton pests usually have different food requirements in the larval and adult stages to develop and survive through the season. In contrast, adult pests particularly Helicoverpa spp. can normally lay their eggs without any feeding, relying only on food reserves transferred from their larval stage. Helicoverpa spp. are highly migratory and can rapidly infest cotton crops and lay their eggs. Unless natural enemies are present and well established in high numbers before the pest arrive, they cannot respond rapidly enough to control these pests (Fit, 1989; Mensah, 1997, 1999). This paper focuses only on predatory insects and how to incorporate them in pest management decisions.

We are currently evaluating unsprayed strip crops planted beside dryland INGARD cotton as nurseries for beneficial arthropods. In the first season of trial work (1999/2000) lablab was evaluated as a nursery (Scholz et o1. 2000). While lablab harboured some species of predators, it supported few Trichogramma egg parasitoids. Trichogramma wasps are considered important beneficials on the Darling Downs and a nursery crop that supports them, as well as other beneficials, may be useful for managing heliothis and other pests. Consequently, during the 2000/01 cotton season we evaluated unsprayed sorghum, maize and soybean strips as beneficial nurseries for adjacent lNGARD cotton.