Final Report Patterns of cotton lint, seed protein and seed oil accumulation in the field

Honours - Molecular interactions between thielaviopsis basicola and cotton governing the pathogenesis of black root rot

The Australian cotton industry places a large emphasis on IPM. To boost IPM further, along with plant based threshold and monitoring procedures, IPM tools are needed. Salt mixtures are considered to be one such tool to reduce chemical rates and to decrease impact of the chemicals on beneficial insects, without reducing the efficacy to the target pest. Further research is needed to identify more chemicals that can mix with salt against mirids and stinkbugs. As with salt mixtures, biopesticides based on fungal pathogens and plant volatiles may be a useful IPM tool in managing mirids and stinkbugs with minimal disruption. The aim of this report is to present the results of the studies conducted to develop plant based thresholds and monitoring procedures for mirids and to develop a management strategy to fit with the existing IPM systems.

Final Report Modified use of the CSIRO sirolan-tensor wool fibre strength

Integrated pest management (IPM) is currently the most acceptable approach to pest control in the Australian Cotton Industry. The adoption of IPM in the cotton industry may be regarded as a continuous journey of discovery. Cotton growers are continuously learning about tools and strategies that can be used in IPM in order to minimise synthetic insecticide use. The introduction of Boilgard cotton crops will be a major boost and also a platform for IPM adoption in Bollgard cotton cropping systems. However, cotton growers will continue to grow conventional cotton crops alongside Bollgard crops as they learn more about the management of Bollgard crops for maximum yield and profitability. Subsequently, cotton growers will need new tools and strategies to manage pests on both Bollgard and conventional cotton crops with minimal synthetic insecticide intervention

Nuclear polyhedrosis virus (NPV) and Bacillus thuringiensis (Bt) are the most commonly used biopesticides for the control of Helicoverpa spp. larvae on cotton crops in Australia. These naturally occurring entomopathogens can regulate populations in agricultural and forestry ecosystems. However, in many instances, entomopathogens have not provided consistent control of pests to an acceptable level (Benz 1987) and in some cases yield loss has occurred (Mensah 2002). In Australia, NPV and foliar Bt are used to control Helicoverpa spp. on conventional cotton crops particularly early in the cotton season. The efficacy of NPV and Bt against Helicoverpa spp. larvae is often found to be inconsistent and can be inadequate when population pressure is high (Mensah 2002). This may be due to the narrow host range, retarded response and/or poor residual activity of biopesticides after application (McGuire 2000). Ultra-violet light (UV) is known to cause pathogens such as NPV and Bt to lose at least half their original activity within days of being applied in the field (Bull et al. 1976; Krieg et al 1980; Jeyakumar and Gupta, 1999). For these biopesticides to fulfil their role as effective, selective Iarvicides in cotton, it is essential that their persistence and efficacy be improved. Most studies aimed at overcoming the constraints of short persistence and low efficacy of entomopathogens, have focussed on the formulation of the pathogens, viz. fungi virus and Bt in oils within a biologically based framework (Inglis et al 2000). Oil based formulations has been reported to increase the adhesion of propagules to the insect integument, enhance spread of inoculum over the insect body, enhance penetration of the insect cuticle, protect propagules from ultra-violet radiation and enhance infection under low humidity (Ingris et al.2000). Recent research on citrus and a range of other horticultural crops led to the development of a PSO formulation which incorporated heavy base oil for maximum efficacy (Beattie et al. 1995, Beattie and Smith 1997) and UV light absorbing compounds to reduce the detrimental effects of UV light on unstable oil molecules. Minimising UV induced breakdown of the petroleum base oil can in turn reduce the potential of the PSO to damage plants (Hodgkinson et al 2002a; Hodgkinson et al 2002b). Further PSOs were developed based on this premise, to improve the effectiveness of UV labile biopesticides against cotton pests. The aim of this study was to determine the effect on persistence and efficacy of NPV and Bt of a UV protected PSO. The effect was measured by the control of Helicoverpa spp larvae, in relation to days after treatment application.

Petroleum spray oils (PSOs) are now an essential part of many integrated pest management (IPM) programs in agricultural crops (Beattie et al. 1995; Mensah et al. 1995). Despite these benefits, the use of PSOs has been limited in cotton due to a perceived risk of PSO-induced phytotoxicity and the fact that PSOs do not have a quick kill effect. Recent research on citrus and a range of other horticultural crops had led to the development of PSO additives such as UV light absorbers that can reduce the risk of phytotoxicity. The additives also enhance the persistence and activity of UV sensitive products such as biological insecticides to improve their efficacy and also can be mixed with synthetic insecticides to improve efficacy against a wide range of pests (see Mensah at al this proceedings; Beattie et al. 1995; Mensah, et al 1995; Jeyakumar and Gupta, 1999). The mode of action of PSOs appears to be multifaceted. Recent studies by Mensah et al. (2001, 2000) have shown that application of PSOs can affect Helicoverpa spp. egg lays on a range of host plants. Deterrence of oviposition by any compound or product against any pest should have a significant effect on the pests&#39 population by reducing the number of eggs deposited by pests on the plant leading to a reduced pest population (Hagen et al 1971). For cotton growers to utilize the oviposition deterrent activity of PSOs in their pest management program, they need to understand the mechanisms underlying the oviposition deterrent activity of PSOs. This will give growers a detail understanding of PSO use pattern effective against cotton pests particularly Helicoverpa spp. The aim of this study was to determine the mechanism that may be involved in the oviposition deterrence activity of PSO against Helicoverpa spp

Petroleum spray oils (PSOs) have been used for many decades to control a wide range of crop pests (Beattie et al 1995) and are known to have little impact on natural enemies of crop pests (Mensah et al 1995). They form an essential part of many integrated pest management (IPM) programs (Beattie and Smith 1997). Despite these benefits, the use of PSOs in the Australian cotton industry has been limited due to a perceived risk of PSO-induced phytotoxicity. In addition, since PSOs do not have quick knockdown effect like synthetic insecticides, growers do not consider PSOs as appropriate products to use against major cotton pests such as Helicoverpa spp. when their economic threshold is reached. However, historical research has shown that the risk of PSO-induced phytotoxicity can be minimised when a number of key base oil properties are considered in good practice PSO formulation. According to Johnson (1994) the use of a high quality base oil of no less than 91% unsulfonatable residues will ensure that few unsaturated compounds remain in the base oil to cause phytotoxicity. Subsequently, research on citrus and a range of other horticultural crops has led to the development of new PSO formulations, some containing UV light absorbers to eliminate photo-oxidation to further reduce the risk of phytotoxicity. Furthermore, there has been increasing evidence that PSOs similar to summer spray are appropriate for use in cotton to reduce numbers of Helicoverpa spp. eggs and to suffocate larvae (Mensah et al 1995; Liu and Stansly 1995). The insecticidal efficacy of PSOs is related to their viscosities (Johnson, 1994; Beattie at al 1995; Rae at al 1997 and Lui et al 2001). As a result there is a need to undertake studies using high viscosity oils for the management of Helicoverpa spp. on commercial cotton crops. The aim of this study was to determine the efficacy of high viscosity PSO and other crop oils as a stand-alone insecticidal product for activity against Helicoverpa spp. on cotton.

Trichogramma pretiosum Riley is an important parasitoid of heliothis (Helicoverpa spp.) eggs throughout the Darling Downs. In the past heliothis have been managed using broad spectrum insecticides such as pyrethroids and organophosphates. These insecticides usually cause high mortality of Trichogramma and other beneficial insects. Increasingly farmers and consultants are looking for soft chemistry to control pests without killing the beneficial arthropods in the farming system. Paraffin oils are now being explored as an option to control heliothis in cotton without causing high mortality of beneficial arthropods. Trichogramma are particularly sensitive to chemical insecticides and can act as bioindicators of the toxicity of insecticidal products. If an insecticide does not impact on Trichogramma it is likely that it will be conducive to most of the beneficial fauna in the farm ecosystem. This report documents the impact of two paraffin oils (Biopest' and Canopy') on Trichogramma pretiosum during larval, pupal and adult stages of development.

Trichogramma pretiosum is a key natural enemy of heliothis (Helicoverpa spp. ) on the Darling Downs. The data presented here describe some of the biological parameters of T. pretiosum, and may be useful in future population models that predict the impact of this valuable egg parasitoid on heliothis. Here we report on the lifespan, parasitism levels and progeny production of T. pretiosum reared on Helilicoverpa armigera in the laboratory.