IXth International Symposium on Thysanoptera and Tospoviruses, 31st August-4th September 2009, Sea World Resort, Queensland, Australia.

This proceedings contains abstracts of 108 papers focusing on the different Tospovirus diseases of various crops and their thysanopteran vectors. The genetics of these pests and pathogens, the different methods used in their control and their geographical distribution are also highlighted.

In vitro infection of sheep lice (Bovicola ovis Schrank) by Steinernematid and Heterorhabditid nematodes.

Control of sheep lice with conventional pesticides can be compromised by difficulty in contacting lice in the dense water repellent fleeces of sheep, particularly when sheep have not been recently shorn. Entomopathogenic nematodes (ENs) are motile and are able to actively seek out insect hosts. They have particular advantages for the control of pests in cryptic habitats, such as the fleeces of sheep and avoid many of the problems frequently associated with chemical controls. This study investigated whether ENs were able infect and kill Bovicola ovis and compared the effectiveness of different species at different temperatures and when applied to wool. Four species of nematodes, Steinernema carpocapsae, Steinernema riobrave, Steinernema feltiae and Heterorhabditis bacteriophora were tested. All were shown to infect and kill lice in Petri dish assays at 30C. At 35C, the percent infection for S. carpocapsae and S. riobrave was significantly higher than for the other two species and percent infection by S. feltiae was significantly greater than for H. bacteriophora (P<0.05). At 37C the percent mortality induced by S. riobrave was significantly greater than for S. carpocapsae (P<0.05). All species were able to locate and infect lice in wool when formulated in water with 8% Tween 80. In wool assays the percent lice infected with nematodes was significantly greater for S. riobrave than H.bacteriophora at 25C, but there were no other differences between species (P=0.05). S. carpocapsae, S. riobrave and S. feltiae caused significantly higher lice mortality than H. bacteriophora at both 25 and 35C in wool assays, but mortality induced by the three steinernematid species did not differ significantly (P>0.05). It is concluded that of the ENs studied S. riobrave is likely to be most effective against B. ovis when applied to live sheep because of its greater tolerance to high temperatures and 'cruiser' foraging strategy .

Healthy hardwoods. A field guide to pests, diseases and nutritional disorders in subtropical hardwoods.

Healthy hardwoods: A field guide to pests, diseases and nutritional disorders in subtropical hardwoods can be used to help identify the common damaging insects, fungi and nutritional disorders in young eucalypt (Eucalyptus and Corymbia species) plantations in subtropical eastern Australia. This guide includes photographs of each insect, fungus and nutritional disorder and the damage they cause, along with a brief description to aid identification. A brief host list for insects and fungi, including susceptibility and occurrence, is provided as a guide only. A hand lens will be useful, especially to identify fungi. Although it is possible to identify insects and fungi from these photographs, laboratory examination will sometimes be necessary. For example, microscopes and culturing media might be used to identify fungi. Information about four exotic pests and diseases has also been included in the Biosecurity threats chapter. Potentially, these would have a severe impact on plantation and natural forests if introduced into Australia. To prevent establishment of these pests, early detection and identification is crucial. If an exotic insect or disease is suspected, then an immediate response is required. Usually, the first response will be to contact the nearest Australian Quarantine and Inspection Service office or forestry agency to seek advice.

Relative host plant species use by the lantana biological control agent Aconophora compressa (Membracidae) across its native and introduced ranges

Aconophora compressa Walker (Hemiptera: Membracidae) was released in 1995 against the weed lantana in Australia, and is now found on multiple host plant species. The intensity and regularity at which A. compressa uses different host species was quantified in its introduced Australian range and also its native Mexican range. In Australia, host plants fell into three statistically defined categories, as indicated by the relative rates and intensities at which they were used in the field. Fiddlewood (Citharexylum spinosum L.: Verbenaceae) was used much more regularly and at higher densities than any other host sampled, and alone made up the first group. The second group, lantana (Lantana camara L.: Verbenaceae; pink variety) and geisha girl (Duranta erecta L.: Verbenaceae), were used less regularly and at much lower densities than fiddlewood. The third group, Sheena’s gold (another variety of D. erecta), jacaranda (Jacaranda mimosifolia D. Don: Bignoniaceae) and myoporum (Myoporum acuminatum R. Br.: Myoporaceae), were used infrequently and at even lower densities. In Mexico, the insect was found at relatively low densities on all hosts relative to those in Australia. Densities were highest on L. urticifolia, D. erecta and Tecoma stans (L.) Juss. ex Kunth (Bignoniaceae), which were used at similar rates to one another. It was found also on a few other verbenaceous and non-verbenaceous host species but at even lower densities. The relative rate at which Citharexylum spp. and L. urticifolia were used could not be assessed in Mexico because A. compressa was found on only one plant of each species in areas where these host species co-occurred. The low rate at which A. compressa occurred on fiddlewood in Mexico is likely to be an artefact of the short-term nature of the surveys or differences in the suites of Citharexylum and Lantana species available there. These results provide further incentive to insist on structured and quantified surveys of non-target host use in the native range of potential biological control agents prior to host testing studies in quarantine.

Assessing the biological control potential of an adventitiously-established "pest", Scirtothrips aurantii (Faure), on a weed, Bryophyllum delagoense (Eckl. & Zeyh.), in Queensland

South African citrus thrips (Scirtothrips aurantii) established adventitiously in Australia. Although it is a major horticultural pest in Africa, it is now advocated as a possible biological control agent against Bryophyllum delagoense Eckl. & Zeyh. (Crassulaceae). To evaluate the biocontrol potential of S. aurantii a two year field study was conducted on the western Darling Downs of southern Queensland. Imidacloprid insecticide was applied to two quadrats at each of 18 field sites to assess, in the absence of S. aurantii, the persistence of individual plants and to quantify propagule production and recruitment by this declared weed. A third quadrat was left, as a control, to be infested naturally by S. aurantii. When released from herbivory by thrips in the field, plants grew significantly more, flowered more, and were significantly more fecund than plants in the quadrats with S. aurantii. Increases in growth and fecundity translated into significantly increased plant numbers but not increased recruitment. Recruitment even declined in experimental quadrats, through the indirect effects of releasing plants from herbivory. Field sampling also revealed that S. aurantii may be sensitive to seasonal climatic fluctuations. These and other local climatic influences may limit the biological control potential of the insect.

Hardwood Plantation P&D Semiochemistry

Insects can cause considerable damage in hardwood plantations and because pesticide use is controversial, future pest management may rely on manipulating insect behaviour. Insects use infochemical cues to identify and locate mates and host plants and this can be used to manipulate their behaviour and reduce pest impacts in plantations. Infochemicals include chemical signals produced by insects, such as pheromones and kairomones, or those produced by host plants as odours or volatiles that are attractive to insects. This research is learning how insects perceive and interact with chemical cues or infochemicals in their environment and how these interactions can be manipulated for monitoring and control. Pest species being investigated include the giant wood moth (Endoxyla cinerea), Culama wood moths, the eucalypt leaf beetle (Paropsis atomaria), red cedar tip moth (Hypsipyla robusta) and several longicorn wood borers. The project will contribute to new strategies for minimising damage and controlling pest densities in Queensland's hardwood plantations.

Refining Integrated Pest Management (IPM) of eggfruit caterpillar

Investigations into pheromone monitoring and efficacy of insecticides to improve Integrated Pest Management (IPM) of eggfruit caterpillar.

Impact of Stem Defect Agent Defects on Hardwood Wood Quality

Queensland's hardwood plantation industry is producing increasing volumes of sawlog, veneer and poles. Wood quality can sometimes be impaired in some plantation hardwoods when the growing trees are attacked by insect borers. Susceptibility to borer damage varies with the species as well as site conditions or location. The risk model developed from this project will enable the plantation industry to match tree species with appropriate growing conditions in Queensland.

Cellular and molecular interactions of rhabdoviruses

Cellular and molecular interactions of rhabdoviruses with their plant hosts and insect vectors.

Biological Control of Eucalypt Pests Overseas and Australia

This project aims to address the growing need for a coordinated approach to research into the biological control of Australian eucalypt insect pests by scoping the formation of a Centre in Australia which would (a) coordinate the evaluation and provision of biological control agents (initially to South Africa and Brazil, but in future years more widely), (b) research the role natural enemies play in pest population regulation in Australian eucalypt plantations and how this may be enhanced as a management tool, and (c) form a network focussed on forest biosecurity with an emphasis on eucalypt pests and pathogens.

Value chain technical development

Short-term research projects on insect pest management in processed food.

CRC50151 Resistance Management

Develop nationally agreed, standard methods for insect sample collection, resistance testing, and data management as a basis for a statistically robust and informative national resistance monitoring program.

Pests and Diseases in Field Crops

Insect pest diagnostics.

CRC60125 Grain Biosecurity Training Program

CRC60125 Grain Biosecurity Training Program. Stored grain is subject to major biosecurity problems which have the potential to significantly reduce the quality of the stored grain and to make it unsuitable for both domestic and international markets. The problems include attack by insect pests, rodents, birds and pathogens like fungi, as well as contamination by weed seeds, mycotoxins and pest faeces.

Integrated Cotton Farming Systems for Central Queensland

This project has delivered outcomes that address major agronomic and crop protection issues closely linked to the profitability and sustainability of cotton production enterprises in CQ. From an agronomic perspective, the CQ environment was always though to support economically viable cotton production in a wide sowing window from the middle of September to early January prior to this research. The ideal positioning of Bollgard II varieties in the CQ planting window was, therefore, critical to the future of the local cotton industry because growers needed baseline information to determine how best to take advantage of the higher yield potential offered by the Bt cotton technology, optimise irrigation water use and fibre characteristics. The project’s outputs include a number of key agronomic findings. Over three growing seasons, Bollgard II crop planted in the traditional sowing window from the middle of September to the end of October consistently produced the highest yields. The project delivers a clear and quantitative assessment of the impacts of planting outside the traditional cropping window - a yield penalty of between 1-4 bales/ha for November and December planted cotton. Whilst yield penalties associated with December-planted crops are clearly linked to declining heat units in the second half of the crop and a cool finish, those associated with November-planted cotton are not consistent with the theoretical yield potential for this sowing date. Further research to understand and minimize the physiological constraints on November-planted cotton would give CQ cotton growers far greater flexibility to develop mixed/double/rotation cropping farming systems that are relevant to the rapidly evolving nature of Agricultural production in Australia. The equivalence of cultivar types with clearly distinguishable, genetically based growth habits, demonstrated in this project, gives growers important information for making varietal choices. The entomological outcomes of this project represent strategic and tactical tools that are highly relevant to the viability and profitability of the cotton industry in Australia. The future of the cotton industry is inextricably linked to the survival and efficacy of GM cotton. Research done in the Callide irrigation area demonstrates the unquestionable potential for development of alternative and highly effective resistance management strategies for Bollgard II using novel technologies and strategies based on products such as Magnet®. Magnet® and similar technologies will be increasingly important in strategies to preserve the shelf life and efficacy of current and future generations of GM technology. However, more research will be required to address logistical and operational issues related to these new technologies before they can be fully exploited in commercial production systems. From an economic perspective, SLW is the sleeping giant in terms of insect nemeses of cotton, particularly from the standpoint of climate change and an increasingly warmer production environment. An effective sampling and management strategy for SLW which has been delivered by this project will go a long way towards minimising production costs in an environment characterised by rapidly rising input costs. SLW has the potential to permanently debilitate the national cotton industry by influencing market sentiment and quality perceptions. Field validation of the SLW population sampling models and management options in the Dawson irrigation area cotton and southern Queensland during 2006-07 documents the robustness of the entomological research outcomes achieved through this project.