A difficulty faced by growers using nucleopolyhedrovirus (NPV) products such as Gemstar can be inconsistency of the products' performance for Helicoverpa spp. control. This problem has lead to the advent of additives developed to improve biopesticide performance. In this paper we investigated several liquid additives for their potential to augment the performance of Gemstar. The results suggest that Aminofeed and Aminofeed UV both increase the efficacy of Gemstar.

The cotton growing environment can be a high risk environment for bees. Periods of extended dry weather can make cotton one of the most attractive sources of pollen and nectar for honey bees, as pollen sources in native vegetation become increasingly scarce. Cotton is recognised by the honey bee industry as a potentially useful feed source for bee breeding and honey production. The reduced reliance on insecticides in the cotton industry has increased the willingness of some hive owners to place bees in close proximity to cotton – meaning growers should be vigilant to the presence of honey bee hives in their area, particularly as honey bees can travel for up to seven kilometres in search of pollen and nectar.

Historically, green mirids are common pests of seedling cotton but not during fruit set and green vegetable bugs(GVB) are rarely a problem. This is because broad-spectrum pesticides applied against Helicoverpa larvae usually control mirids and GVB through the rind- and late season. With the introduction of Bt-cotton however, the number of Helicoverpa sprays used has declined allowing green mirids and GVB to build to potentially damaging levels in some instances. Spraying for Helicoverpa is expected to drop even further with two-gene cotton (Bollgard II), raising the concern that sucking pests may become a significant problem during the fruiting period. The effect on yield and fibre quality by the increased feeding of mirids and GVB on bolls not well understood. In one of the few studies to date, Khan and Bauer (2001) found that damage to young bolls(<10 days old) often causes shedding. Damage to older bolls (10-20 days old) usually does not cause shedding but the damaged locules may not develop properly. This has implications for the capacity of the crop to compensate for damage by producing more bolls, making undamaged bolls larger or making undamaged locules in damaged bons larger.

Ladybirds are common beneficial predators that feed primarily on a aphids in Australian cotton crops. Predation by ladybirds Helicoverpa spp. eggs has been observed, however the relationship between predator density, egg density, aphid availability and habitat size has not been investigated. Under laboratory conditions three banded ladybirds were the most effective egg predators and variable ladybirds the least effective of the four ladybird species tested. In greenhouse experiments three banded and variable ladybirds showed similar predatory capability and under natural conditions variable ladybirds may be the most effective coccinellid predators of Helicoverpa spp.

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.