Functional analysis of Bacillus thuringiensis crystal toxins. Pore-forming toxins, such as anthrax, hemolysin, cholera and diphtheria toxins, are among the most virulent microbial toxins, posing a threat to humans and lifestock. We are using a novel functional approach to test possible lectin and antimicrobial peptide functions of a typical and economically important pore-forming toxin, the crystal endotoxin from Bacillus thuringiensis, to examine why toxicity of the lectin-containing toxin is ....Functional analysis of Bacillus thuringiensis crystal toxins. Pore-forming toxins, such as anthrax, hemolysin, cholera and diphtheria toxins, are among the most virulent microbial toxins, posing a threat to humans and lifestock. We are using a novel functional approach to test possible lectin and antimicrobial peptide functions of a typical and economically important pore-forming toxin, the crystal endotoxin from Bacillus thuringiensis, to examine why toxicity of the lectin-containing toxin is restricted to invertebrates only, while the amphipathic peptide alone is also toxic to many vertebrate cells. The outcome of these experiments has important implications for the sustainable use of biopesticides and for the prevention and containment of infectious diseases.Read moreRead less
Mechanisms and management of inducible tolerance to synthetic insecticides and Bacillus thuringiensis (Bt)-formulations in Australian populations of diamondback moth. Insects have a cunning ability to respond to damaging environments by evolving genetic resistance or mobilising metabolic tolerance mechanisms. Recent observations of inducible tolerance to synthetic and biopesticides, which can be transmitted to offspring by a maternal effect has the potential to cause ecological and economic prob ....Mechanisms and management of inducible tolerance to synthetic insecticides and Bacillus thuringiensis (Bt)-formulations in Australian populations of diamondback moth. Insects have a cunning ability to respond to damaging environments by evolving genetic resistance or mobilising metabolic tolerance mechanisms. Recent observations of inducible tolerance to synthetic and biopesticides, which can be transmitted to offspring by a maternal effect has the potential to cause ecological and economic problems in agricultural production. We will use field-collected Diamondback moth (DBM), a major insect pest in canola and brassica vegetable crops, to investigate the genetic implications of inducible tolerance for the integrated management of DBM and for the design of new resistance management strategies.Read moreRead less
Beneficial arthropods in Coonawarra vineyards and sustainable grape production. Many species of pest and beneficial arthropods live in vines and groundcover of vineyards. Vignerons often devote considerable effort to sustain populations of what they believe to be beneficial arthropods. However, the types of natural enemies and techniques to enhance their effectiveness are poorly known. This project aims to identify and quantify the role of natural enemies in controlling the main pest in Coonawar ....Beneficial arthropods in Coonawarra vineyards and sustainable grape production. Many species of pest and beneficial arthropods live in vines and groundcover of vineyards. Vignerons often devote considerable effort to sustain populations of what they believe to be beneficial arthropods. However, the types of natural enemies and techniques to enhance their effectiveness are poorly known. This project aims to identify and quantify the role of natural enemies in controlling the main pest in Coonawarra vineyards, identify their food and shelter requirements, and improve management practices and other techniques to optimise populations of beneficial species. The significance of this project is that it will enable the promotion of insecticide-free production of winegrapes in the Coonawarra.Read moreRead less
Cell-free immune reactions and suppression. Insects pests and insect vectors of diseases are managed by toxic substances, but insects have a cunning ability to persist. How pesticide-tolerant insect pests recognise and inactivate chemical and biological toxins is poorly understood. While vertebrates with a closed circulatory system use coagulation reactions mainly for wound-healing, invertebrates employ cell-free aggregation reactions for the sequestration and inactivation of potentially damagin ....Cell-free immune reactions and suppression. Insects pests and insect vectors of diseases are managed by toxic substances, but insects have a cunning ability to persist. How pesticide-tolerant insect pests recognise and inactivate chemical and biological toxins is poorly understood. While vertebrates with a closed circulatory system use coagulation reactions mainly for wound-healing, invertebrates employ cell-free aggregation reactions for the sequestration and inactivation of potentially damaging objects and substances. We use insect plasma to dissect recognition and inactivation of damaging objects and substances with the aim to understand tolerance and its inhibition to design novel strategies in delaying tolerance to pesticides in insect pests.Read moreRead less
Genetic variation in the Cotesia flavipes complex of parasitic wasps: towards the effective biological control of stem-borer pests. This project will determine the genetic variation among world populations of the parasitic wasp Cotesia flavipes, as a prelude to the preemptive biological control of stemborer pests of sugarcane in Australia. These pests currently do not occur in Australia, but are found in crops across New Guinea and Indonesia, so that their incursion into Australia is highly lik ....Genetic variation in the Cotesia flavipes complex of parasitic wasps: towards the effective biological control of stem-borer pests. This project will determine the genetic variation among world populations of the parasitic wasp Cotesia flavipes, as a prelude to the preemptive biological control of stemborer pests of sugarcane in Australia. These pests currently do not occur in Australia, but are found in crops across New Guinea and Indonesia, so that their incursion into Australia is highly likely in the future. The results of this project will clarify the taxonomic status of C. flavipes-like species in Australia and provide the means, using molecular markers, to select host strains of this wasp suitable for the control of specific stemborer speciesRead moreRead less
Phylogeography and host specificity of stemborer parasitoids: essential components for the pre-emptive biocontrol of sugarcane pests in Australia. Stemboring insects cause huge economic losses to the sugar industry world-wide but fortunately these pests are largely absent from Australia, in part because quarantine measures have prevented their introduction. However, given their proximity, incursion of foreign stemborers from Asia pose a serious threat to Australian sugarcane. To prepare effectiv ....Phylogeography and host specificity of stemborer parasitoids: essential components for the pre-emptive biocontrol of sugarcane pests in Australia. Stemboring insects cause huge economic losses to the sugar industry world-wide but fortunately these pests are largely absent from Australia, in part because quarantine measures have prevented their introduction. However, given their proximity, incursion of foreign stemborers from Asia pose a serious threat to Australian sugarcane. To prepare effective pest management plans that can be adopted promptly in a worst-case scenario, this study will 1) develop molecular diagnostic tools to select wasp biocontrol agents that are suitable for the control of specific foreign stemborer pests, and 2) evaluate whether any Australian native wasps have the ability to kill foreign stemborers. Read moreRead less
Systematics and coevolution of insect herbivores on casuarinas: testing phylogenetic congruence for selection of plant biocontrol agents. The casuarinas (sheoaks) are a significant component of the Australian floral landscape. Associated with them are many co-evolved insects, some of which may prove useful as biocontrol agents against Casuarina weeds. Using morphological taxonomy combined with a novel molecular approach, we will compare the co-evolution of psyllids, scale and gall insects, and w ....Systematics and coevolution of insect herbivores on casuarinas: testing phylogenetic congruence for selection of plant biocontrol agents. The casuarinas (sheoaks) are a significant component of the Australian floral landscape. Associated with them are many co-evolved insects, some of which may prove useful as biocontrol agents against Casuarina weeds. Using morphological taxonomy combined with a novel molecular approach, we will compare the co-evolution of psyllids, scale and gall insects, and weevils with that of the casuarinas. This project will have significant implications for conservation and regeneration of casuarinas in the Australian context and the selection of specific biocontrol agents against casuarinas as environmental weeds.Read moreRead less