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Nayak M.K.,Australian Department of Primary Industries and Fisheries | Nayak M.K.,Cooperative Research Center for National Plant Biosecurity
Pest Management Science | Year: 2010

BACKGROUND: Piperonyl butoxide (PB)-synergised natural pyrethrins (pyrethrin:PB ratio 1: 4) were evaluated both as a grain protectant and a disinfestant against four Liposcelidid psocids: Liposcelis bostrychophila Badonnel, L. entomophila (Enderlein), L. decolor (Pearman) and L. paeta Pearman. These are key storage pests in Australia that are difficult to control with the registered grain protectants and are increasingly being reported as pests of stored products in other countries. Firstly, mortality and reproduction of adults were determined in wheat freshly treated at 0.0, 0.75, 1.5, 3 and 6 mg kg-1 of pyrethrins + PB (1: 4) at 30 ± 1°C and 70 ± 2% RH. Next, wheat treated at 0.0, 1.5, 3 and 6 mg kg-1 of pyrethrins + PB (1: 4) was stored at 30 ± 1 °C and 70 ± 2% RH and mortality and reproduction of psocids were assessed after 0, 1.5, 3 and 4.5 months of storage. Finally, the potential of synergised pyrethrins as a disinfestant was assessed by establishing time to endpoint mortality for adult psocids exposed to wheat treated at 3 and 6 mg kg-1 of synergised pyrethrins after 0, 3, 6, 9 and 12 h of exposure. RESULTS: Synergised pyrethrins at 6 mg kg-1 provided 3 months of protection against all four Liposcelis spp., and at this rate complete adult mortality of these psocids can be achieved within 6 h of exposure. CONCLUSION: Piperonyl butoxide-synergised pyrethrins have excellent potential both as a grain protectant and as a disinfestant against Liposcelidid psocids. © State of Queensland, Department of Employment, Economic Development and Innovation, 2010. Published by John Wiley and Sons, Ltd.

Paini D.R.,Cooperative Research Center for National Plant Biosecurity | Paini D.R.,CSIRO | Yemshanov D.,Natural Resources Canada
PLoS ONE | Year: 2012

Species can sometimes spread significant distances beyond their natural dispersal ability by anthropogenic means. International shipping routes and the transport of shipping containers, in particular are a commonly recognised pathway for the introduction of invasive species. Species can gain access to a shipping container and remain inside, hidden and undetected for long periods. Currently, government biosecurity agencies charged with intercepting and removing these invasive species when they arrive to a county's border only assess the most immediate point of loading in evaluating a shipping container's risk profile. However, an invasive species could have infested a container previous to this point and travelled undetected before arriving at the border. To assess arrival risk for an invasive species requires analysing the international shipping network in order to identify the most likely source countries and the domestic ports of entry where the species is likely to arrive. We analysed an international shipping network and generated pathway simulations using a first-order Markov chain model to identify possible source ports and countries for the arrival of Khapra beetle (Trogoderma granarium) to Australia. We found Kaohsiung (Taiwan) and Busan (Republic of Korea) to be the most likely sources for Khapra beetle arrival, while the port of Melbourne was the most likely point of entry to Australia. Sensitivity analysis revealed significant stability in the rankings of foreign and Australian ports. This methodology provides a reliable modelling tool to identify and rank possible sources for an invasive species that could arrive at some time in the future. Such model outputs can be used by biosecurity agencies concerned with inspecting incoming shipping containers and wishing to optimise their inspection protocols. © 2012 Paini, Yemshanov.

Clarke A.R.,Queensland University of Technology | Clarke A.R.,Cooperative Research Center for National Plant Biosecurity | Powell K.S.,Australian Department of Primary Industries and Fisheries | Weldon C.W.,Stellenbosch University | Taylor P.W.,Macquarie University
Annals of Applied Biology | Year: 2011

The distribution, systematics and ecology of Bactrocera tryoni, the Queensland fruit fly, are reviewed. Bactrocera tryoni is a member of the B. tryoni complex of species, which currently includes four named species, viz. B. tryoni ssp., B. neohumeralis, B. melas and B. aquilonis. The species status of B. melas and B. aquilonis is unclear (they may be junior synonyms of B. tryoni) and their validity, or otherwise, needs to be confirmed as a matter of urgency. While Queensland fruit fly is regarded as a tropical species, it cannot be assumed that its distribution will spread further south under climate change scenarios. Increasing aridity and hot dry summers, as well as more complex, indirect interactions resulting from elevated CO2, make predicting the future distribution and abundance of B. tryoni difficult. The ecology of B. tryoni is reviewed with respect to current control approaches (with the exception of sterile insect technique (SIT) which is covered in a companion paper). We conclude that there are major gaps in the knowledge required to implement most noninsecticide-based management approaches. Priority areas for future research include host-plant interactions, protein and cue-lure foraging and use, spatial dynamics, development of new monitoring tools, investigating the use of natural enemies and better integration of fruit flies into general horticultural IPM systems. © 2010 Association of Applied Biologists.

Renton M.,University of Western Australia | Renton M.,Murdoch University | Renton M.,CSIRO | Renton M.,Cooperative Research Center for National Plant Biosecurity | And 2 more authors.
Global Change Biology | Year: 2012

In the next century, global climate change is predicted to have large influences on species' distributions. Much of the research in this area has focused on predicting the areas where conditions will be suitable for the species in future, and thus the potential distribution of the species. However, it is equally important to predict the relative abilities of species to migrate into new suitable areas as conditions shift, while accounting for dynamic processes, such as dispersal, maturation, mortality, and reproduction, as well as landscape characteristics, such as level of habitat fragmentation and connectivity. In this study, we developed a spatially explicit individual-based model that addresses these factors. As a motivating case study, we based aspects of the model on southwest Australia, a global biodiversity hotspot, but stress that the results obtained are generalizable beyond this region. Using the model, we enhanced current understanding of climate change impacts by investigating how and to what extent the functional traits of plant species affect their ability to move with climate change across landscapes with various levels of fragmentation. We also tested the efficacy of strategic restoration, such as planting corridors to increase connectivity among fragments. We found that even if the landscape is fully intact, only an average of 34.2% of all simulated functional groups had a good chance of successfully tracking climate change. However, our study highlights the power of strategic restoration as a tool for increasing species persistence. Corridors linking fragments increased species persistence rates by up to 24%. The lowest persistence rates were found for trees, a functional group with high dispersal but also long generation times. Our results indicate that for trees intervention techniques, such as assisted migration might be required to prevent species losses. © 2012 Blackwell Publishing Ltd.

Kriticos D.J.,Scion Research | Kriticos D.J.,CSIRO | Kriticos D.J.,Cooperative Research Center for National Plant Biosecurity
Biological Invasions | Year: 2012

Managing the threats posed by invasive alien species currently may involve a mixture of species-specific and pathway-specific policy and operational measures aimed at achieving a socially acceptable level of protection. In order to decide how to allocate scarce biosecurity resources in a manner that avoids erecting technical barriers to trade, it is necessary to undertake risk assessments for individual pests or commodity pathways. Whilst there are popular climatic niche tools available to project future pest risk in terms of a species' potential distribution, the international legal frameworks as yet have no explicit means of including future risk considerations arising from projected climate changes. Nor are there any tested and accepted tools for projecting shifts in geographic pest risk, or systematically identifying future pest risks. I use New Zealand as a case study to demonstrate a method for identifying generic geographic pest risk to a jurisdiction under historical and future climate scenarios. Under future climates, the global area from which threatening pests could originate is set to increase. Pests from some regions that presently require warmer conditions than can be found in New Zealand are likely to become a future threat. These pests will probably originate from regions presently experiencing a sub-tropical climate. As climates warm, regions that have previously been too cool to pose a pest threat will start posing a threat, particularly from rapidly dispersing ruderal species and other generalists. Taking all of the different types of threats into account, the largest increase in risk area for New Zealand appears to be in northern Europe, North America and Asia. This technique can be used to alert biosecurity pathway managers about the shifting direction from which climatically suitable biological invaders may originate, and can also be used to generate pests lists for species that are presently unsuited to the jurisdiction, but may in the future become so if global temperatures rise as expected. The results highlight the need for adaptive biosecurity systems that can recognise and assesses future risk trends, monitor these trends, and are able to respond rapidly to changing threats. © 2011 Springer Science+Business Media B.V.

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